Vegetable Oils in Food Technology: Composition, Properties and Uses

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Vegetable Oils in Food Technology Composition, Properties and Uses Second Edition Edited by

Frank D. Gunstone

A John Wiley & Sons, Ltd., Publication

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This edition first published 2011 © 2011 by Blackwell Publishing Ltd. Blackwell Publishing was acquired by John Wiley & Sons in February 2007. Blackwell’s publishing program has been merged with Wiley’s global Scientific, Technical and Medical business to form Wiley-Blackwell. Registered Office John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK Editorial Offices 9600 Garsington Road, Oxford, OX4 2DQ, UK The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK 2121 State Avenue, Ames, Iowa 50014-8300, USA For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com/wiley-blackwell. The right of the authors to be identified as the authors of this work has been asserted in accordance with the UK Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. Library of Congress Cataloging-in-Publication Data Vegetable oils in food technology : composition, properties and uses / edited by Frank D. Gunstone. – 2nd ed. p. cm. Includes bibliographical references and index. ISBN 978-1-4443-3268-1 (hardcover : alk. paper) 1. Vegetable oils. 2. Food industry and trade. I. Gunstone, Frank D. TP680.V44 2011 664′.3–dc22 2010041148 A catalogue record for this book is available from the British Library. This book is published in the following electronic formats: ePDF 9781444339901; Wiley Online Library 9781444339925; ePub 9781444339918 Set in 10/12pt Times by SPi Publisher Services, Pondicherry, India

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2011

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Contents

Preface to the First Edition Preface to the Second Edition Contributors List of Abbreviations 1 Production and Trade of Vegetable Oils Frank D. Gunstone 1.1 Extraction, refining and processing 1.2 Vegetable oils: Production, consumption and trade 1.2.1 Nine vegetable oils 1.2.2 Palm oil 1.2.3 Soybean oil 1.2.4 Rapeseed/canola oil 1.2.5 Sunflowerseed oil 1.2.6 Groundnut (peanut) oil 1.2.7 Cottonseed oil 1.2.8 Coconut oil 1.2.9 Palmkernel oil 1.2.10 Olive oil 1.2.11 Corn oil 1.2.12 Sesame oil 1.2.13 Linseed oil 1.3 Some topical issues 1.3.1 Imports into China and India 1.3.2 Trade in oilseeds and in vegetable oils 1.3.3 Food and non-food use of vegetable oils 1.3.4 Prices 1.3.5 The food–fuel debate 1.3.6 Predictions for future supply and demand 1.3.7 Sustainability 1.3.8 Genetic modification References 2 Palm Oil Siew Wai Lin 2.1 Introduction 2.2 Composition and properties of palm oil and fractions

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2.2.1 Palm oil 2.2.2 Palm olein 2.2.3 Palm stearin 2.3 Physical characteristics of palm oil products 2.3.1 Palm oil 2.3.2 Palm olein 2.3.3 Palm stearin 2.4 Minor components of palm oil products 2.4.1 Carotenes 2.4.2 Tocopherols and tocotrienols (tocols) 2.4.3 Sterols, squalene and other hydrocarbons 2.5 Food applications of palm oil products 2.5.1 Cooking/frying oil 2.5.2 Margarines 2.5.3 Shortenings 2.5.4 Vanaspati 2.5.5 Cocoa butter equivalents (CBE) 2.5.6 Other uses 2.6 Nutritional aspects of palm oil 2.7 Sustainable palm oil 2.8 Conclusions References 3 Soybean Oil Tong Wang 3.1 Introduction 3.2 Composition of soybean and soybean oil 3.2.1 Seed composition 3.2.2 Oil composition 3.2.3 Fatty acid composition 3.2.4 Minor components 3.3 Recovery and refining of soybean oil 3.3.1 Oil extraction 3.3.2 Oil refining 3.3.3 Modified non-alkaline refining 3.3.4 Co-products from oil refining 3.3.5 Fatty acid esters of glycidol and 3-monochloro-1,2-propanediol as processing contaminants 3.4 Oil composition modification by processing and biotechnology 3.4.1 Hydrogenation 3.4.2 Interesterification 3.4.3 Crystallization and fractionation 3.4.4 Traditional plant breeding and genetic modification 3.4.5 Oxidative and sensory properties of low-linolenic acid soybean oil to replace trans frying oil 3.5 Physical properties of soybean oil 3.5.1 Polymorphism

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3.5.2 Density 3.5.3 Viscosity 3.5.4 Refractive index 3.5.5 Specific heat 3.5.6 Melting point 3.5.7 Heat of combustion 3.5.8 Smoke, flash, and fire points 3.5.9 Solubility 3.5.10 Plasticity and spreadability 3.5.11 Electrical resistivity 3.6 Oxidation evaluation of soybean oil 3.7 Nutritional properties of soybean oil 3.8 Food uses of soybean oil 3.8.1 Cooking and salad oils 3.8.2 Margarine and shortening 3.8.3 Mayonnaise and salad dressing References 4 Canola/Rapeseed Oil Roman Przybylski 4.1 Introduction 4.2 Composition 4.2.1 Nature of edible oils and fats 4.2.2 Fatty acid composition of canola oil 4.2.3 Minor fatty acids 4.2.4 Triacylglycerols 4.2.5 Polar lipids 4.2.6 Tocopherols 4.2.7 Sterols 4.2.8 Pigments 4.2.9 Trace elements 4.2.10 Commercial crude oil, refined, and deodorized oil 4.2.11 Oxidative stability 4.3 Physical and chemical properties 4.3.1 Relative density 4.3.2 Viscosity 4.3.3 Smoke and flash point 4.3.4 Cold test 4.3.5 Crismer value 4.3.6 Saponification number 4.3.7 Iodine value 4.3.8 Melting characteristics, polymorphism, and crystal properties 4.4 Major food uses 4.4.1 Standard canola/rapeseed oil 4.4.2 High-erucic acid rapeseed (HEAR) oil 4.5 Conclusion and outlook References

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5 Sunflower Oil Maria A. Grompone 5.1 Introduction 5.2 Sunflower oil from different types of seed 5.2.1 Regular sunflower seeds 5.2.2 Commercial sunflower oil types 5.2.3 Composition of commercially available sunflower oil types 5.2.4 Other sunflower seed types to be commercialised 5.3 Physical and chemical properties 5.3.1 Relative density 5.3.2 Viscosity 5.3.3 Refractive index 5.3.4 Smoke point, flash point and fire point 5.3.5 Other physical properties 5.4 Melting properties and thermal behaviour 5.4.1 Melting properties of regular sunflower oil 5.4.2 Thermal behaviour of different sunflower oil types 5.5 Extraction and processing of sunflower oil 5.5.1 Preparation of sunflower seeds for extraction 5.5.2 Sunflower oil extraction 5.5.3 Processing of crude sunflower oil 5.6 Modified properties of sunflower oil 5.6.1 Hydrogenation of regular sunflower oil 5.6.2 Interesterification of sunflower oil 5.7 Oxidative stability of commercial sunflower oils 5.7.1 Inherent stability of different commercial sunflower oil types 5.7.2 Shelf-life of sunflower oil 5.7.3 Accelerated ageing of sunflower oil 5.7.4 Stabilisation of sunflower oil by added antioxidants 5.8 Food uses of different sunflower oil types 5.8.1 Use of regular sunflower oil as salad oil and cooking oil 5.8.2 Margarine and shortening 5.9 Frying use of commercial sunflower oil types 5.9.1 Frying use of regular sunflower oil 5.9.2 Frying use of high-oleic sunflower oil 5.9.3 Frying use of mid-oleic sunflower oil 5.9.4 Frying use of sunflower oils with a high content of saturated fatty acids Acknowledgement References 6 The Lauric (Coconut and Palm Kernel) Oils Ibrahim Nuzul Amri 6.1 Introduction 6.2 Coconut oil 6.2.1 Coconut palm

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6.2.2 Coconut oil 6.2.3 Composition 6.2.4 Properties 6.2.5 Trade specifications 6.3 Palm kernel oil 6.3.1 Palm kernel oil 6.3.2 Composition 6.3.3 Properties 6.3.4 Trade specifications 6.4 Processing 6.4.1 Fractionation 6.4.2 Hydrogenation 6.4.3 Interesterification 6.5 Food uses 6.5.1 Frying 6.5.2 Margarine 6.5.3 Medium-chain triacylglycerols 6.5.4 Speciality fats: Cocoa butter substitutes 6.5.5 Filling creams 6.5.6 Non-dairy creamer 6.5.7 Non-dairy whipping cream 6.5.8 Non-dairy cheese 6.5.9 Filled milk 6.5.10 Ice cream 6.5.11 Toffees and caramels 6.6 Health aspects References 7 Cottonseed Oil Michael K. Dowd 7.1 7.2 7.3 7.4

Introduction History Seed composition Oil composition 7.4.1 Triacylglycerol fatty acids 7.4.2 Other oil components 7.4.3 Gossypol 7.5 Chemical and physical properties of cottonseed oil 7.6 Processing 7.6.1 Seed preparation 7.6.2 Oil extraction 7.6.3 Oil finishing 7.6.4 Additional processing 7.7 Cottonseed oil uses 7.8 Co-product uses References

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8 Groundnut (Peanut) Oil Lisa L. Dean, Jack P. Davis, and Timothy H. Sanders 8.1 Peanut production, history, and oil extraction 8.2 Oil uses 8.2.1 Frying and food 8.2.2 Feed 8.3 Composition of groundnut oil 8.3.1 Oil in seed 8.3.2 Fatty acids 8.3.3 High-oleic peanut oil 8.3.4 Triacylglycerol structure 8.3.5 Phospholipids 8.3.6 Sterols 8.3.7 Antioxidants 8.4 Chemical and physical characteristics of groundnut oil 8.4.1 General 8.4.2 Color 8.4.3 Density and viscosity 8.4.4 Melting point/crystallization 8.4.5 Free fatty acid (FFA) 8.4.6 Iodine value (IV) 8.4.7 Peroxide value 8.4.8 Acetyl value 8.4.9 Heat of fusion 8.4.10 Unsaponifiable material 8.5 Health issues 8.5.1 Cardiovascular disease and diabetes 8.5.2 Weight control 8.5.3 Allergy Note References 9 Olive Oil Dimitrios Boskou 9.1 Introduction 9.2 Extraction of olive oil from olives 9.2.1 Pressure 9.2.2 Centrifugation (three-phase system) 9.2.3 Two-phase decanters 9.2.4 Percolation (selective filtration) 9.2.5 Processing aids 9.2.6 Extraction of pomace oil (olive residue oil) 9.3 Olive oil composition 9.3.1 Fatty acids and triacylglycerols 9.3.2 Mono- and di-acylglycerols 9.3.3 Other constituents

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9.4

Effect of processing olives on the composition of virgin olive oils 9.4.1 Aroma compounds 9.4.2 Polyphenols 9.4.3 Other minor constituents 9.5 Refining and modification 9.5.1 Olive oil and olive pomace oil refining 9.5.2 Refining and minor constituents 9.6 Hardening and interesterification 9.7 Quality, genuineness and regulations 9.7.1 Olive oil 9.7.2 Analysis and authentication 9.8 Consumption and culinary applications 9.8.1 Olive oil in frying References 10 Corn Oil Robert A. Moreau 10.1 Composition of corn oil 10.1.1 Introduction: The corn oil industry 10.1.2 Common corn oil refining steps and effects on oil composition 10.1.3 The composition of crude corn oils – comparison of corn germ oil, corn kernel oil, and corn fiber oil 10.1.4 Fatty acid composition of corn triacylglycerols 10.1.5 Triacylglycerol molecular species 10.1.6 Unsaponifiables and phytosterols 10.1.7 Tocopherols and tocotrienols 10.1.8 Carotenoids 10.1.9 Trans fatty acids 10.2 Properties of corn oil 10.2.1 Chemical and physical properties 10.2.2 Stability 10.2.3 Nutritional properties 10.3 Major food uses of corn oil 10.3.1 Cooking/salad oil 10.3.2 Margarines and spreads 10.4 Conclusions References 11 Minor and Speciality Oils S. Prakash Kochhar 11.1 Introduction 11.2 Sesame seed oil 11.2.1 World seed production 11.2.2 Lipid composition 11.2.3 Seed processing and oil refining

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11.2.4 Sesame antioxidants and oil stability 11.2.5 Health-promoting effects 11.3 Rice bran oil 11.3.1 Production of bran and oil extraction 11.3.2 Oil refining and high-value by-products 11.3.3 Lipid composition and food uses 11.3.4 Potential health benefits and future trends 11.4 Flaxseed (linseed and linola) oil 11.4.1 Flax production and oil composition 11.4.2 Edible uses of flaxseed and its oil 11.4.3 Linola oil 11.5 Safflower oil 11.6 Argan kernel oil 11.7 Avocado oil 11.8 Camelina seed oil 11.9 Grape seed oil 11.10 Pumpkin seed oil 11.11 Sea buckthorn oil 11.12 Cocoa butter and CBE 11.12.1 Cocoa butter 11.12.2 Illipe butter (Borneo tallow) 11.12.3 Kokum butter 11.12.4 Sal fat 11.12.5 Shea butter 11.12.6 Mango kernel fat 11.13 Oils containing γ-linolenic acid (GLA) and stearidonic acid (SDA) 11.13.1 Evening primrose oil 11.13.2 Borage oil 11.13.3 Blackcurrant seed oil 11.13.4 Stearidonic acid oils 11.13.5 Nutritional and health benefits of GLA and SDA oils 11.14 Tree nut oils 11.14.1 Brazil nut kernel oil 11.14.2 Hazel nut oil 11.14.3 Macadamia nut oil 11.14.4 Walnut oil 11.14.5 Health benefits of nuts and nut lipids References

297 298 299 299 301 303 305 306 306 308 309 309 313 315 315 317 319 320 321 321 322 322 322 323 324 324 324 325 326 326 327 327 328 328 329 331 331 331

Useful Websites

343

Index

347

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Preface to the First Edition

Our dietary intake comprises three macronutrients (protein, carbohydrate and lipid) and a large but unknown number of micronutrients (vitamins, minerals, antioxidants etc.). Good health rests, in part, on an adequate and balanced supply of these components. This book is concerned with the major sources of lipids and the micronutrients that they contain. Supplies and consumption of oils and fats are generally described in terms of seventeen commodity oils, four of which are of animal origin and the remainder of which are derived from plants. This selection of oils does not include cocoa butter, with an annual production of around 1.7 million tonnes, which is used almost entirely for the purpose of making chocolate. Nor does it include oils consumed in the form of nuts. The production and trade data that are available and are detailed in the first chapter relate to crops either grown and harvested for the oils that they contain (e.g. rape and sunflower oils) or crops that contain oils as significant by-products (e.g. cottonseed and corn oils). Annual production and consumption of oils and fats is about 119 million tonnes and rising steadily at a rate of 2–6 million tonnes per year. This is required to meet the demand, which also grows at around this rate, partly as a consequence of increasing population but more because of increasing income, especially in developing countries. Around 14% of current oil and fat production is used as starting material for the oleochemical industry and around 6% is used as animal feed (and indirectly therefore as human food). The remaining 80% is used for human food – as spreads, frying oil, salad oils, cooking fat etc. These facts provide the framework for this book. After the first chapter on production and trade, there follow ten chapters covering thirteen oils. The four dominant oils are discussed first: soybean, palm, rape/canola and sunflower. These are followed by chapters on two lauric oils (coconut and palmkernel), cottonseed oil, groundnut (peanut) oil, olive oil, corn oil and three minor but interesting oils (sesame, rice bran and flaxseed). The authors – from Europe, Asia and North America – were invited to cover the following topics: the native oils in their original form and in modified forms resulting from partial hydrogenation, fractionation or interesterification, and related oils produced by conventional seed breeding and/or genetic modification. For each of these, information is provided on component triacylglycerols, fatty acids, minor components (phospholipids, sterols, tocols, carotenoids etc.) and their major food uses. The book will serve as a rich source of data on these oils and the important minor components that they contain. It should therefore be of special value to food producers requiring up-to-date information on their raw materials, which will probably already have been processed, at least in part. The editor thanks the authors for their efforts to convert his concept into a reality and for their patience and willing cooperation, and he acknowledges the generous help and advice that he has received from the publisher, Dr Graeme MacKintosh and his colleagues. Frank D. Gunstone

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Preface to the Second Edition

It is nine years since the first edition of this book was published. The success of this led to the idea that we should produce a second, updated and extended edition. Each revised chapter has new information that has been published since 2002 and the final chapter has been extended to cover the more important minor seed oils. As in the first edition, there is an emphasis on data for both the major and minor components present in each oil. Significant changes in the last nine years have been the development of seeds producing oils with a different fatty acid composition based on current nutritional views. For example, there are more high-oleic varieties of several oils. Current views on the nutritional properties of trans acids and the requirement in some countries to report these on food labels have had an influence on avoiding partial hydrogenation and finding alternative ways of producing oils and fats with the required nutritional and physical properties. In the years between 2001/02 and 2008/09, production of the nine major vegetable oils rose 42% from 93 to 132 million tonnes. In this period there was an increased use for nonfood purposes and consequent pressure on the supplies required to meet the food needs of a population growing in number and in disposable income. While many of the chapters have been revised by the original authors, new authors were found for three of the chapters. I am indebted to all the authors for their efforts and for their patience with the editor. I also acknowledge the assistance provided by David McDade and his colleagues at Wiley-Blackwell. Frank D. Gunstone

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Contributors

Dr Dimitrios Boskou Laboratory of Food Chemistry and Technology School of Chemistry Aristotle University of Thessaloniki University Campus, Thessaloniki 54124 Greece Dr Jack P. Davis United States Department of Agriculture Agricultural Research Service Market Quality and Handling Research Unit Box 7624, North Carolina State University Raleigh, NC 27695-7624 USA Dr Lisa L. Dean United States Department of Agriculture Agricultural Research Service Market Quality and Handling Research Unit Box 7624, North Carolina State University Raleigh, NC 27695-7624 USA Dr Michael K. Dowd USDA ARS SRRC 1100 Robert E Lee Blvd New Orleans, LA 70124-4305 USA Professor Maria A. Grompone Av General Flores 2124 Montevideo 11800 Uruguay

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Professor Frank D. Gunstone 3 Dempster Court St Andrews Fife KY16 9EU Scotland Dr Ibrahim Nuzul Amri Malaysian Palm Oil Board 6 Persiaran Institusi 43000 Kajang, Selangor Malaysia Dr S. Prakash Kochhar SPK Consultancy Services 14 Holmemoor Drive Sonning Reading RG4 6TE UK Dr Siew Wai Lin Malaysian Palm Oil Board 6 Persiaran Institusi, 43000 Kajang, Selangor Malaysia Dr Robert A. Moreau Eastern Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania USA Professor Roman Przybylski University of Lethbridge Department of Chemistry and Biochemistry Lethbridge, Alberta Canada T1K 3M4

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Contributors

Dr Timothy H. Sanders United States Department of Agriculture Agricultural Research Service Market Quality and Handling Research Unit Box 7624, North Carolina State University Raleigh, NC 27695-7624 USA

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Professor Tong Wang Department of Food Science and Human Nutrition 2312 Food Sciences Building Iowa State University Ames, Iowa 50011-1061 USA

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List of Abbreviations

ABTS ALA AMF AOCS AOM AP B BCO BF BfR BHA BHT BNO BO CAE CAN cp CB CBE CBI CBR CHD CLA CLnA CO CPKO CPO CVD DAF DAG DGDG DHA DMPS DNA DOBI DPPH DSC EDTA

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2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) alpha-linolenic acid (18:3n-3, all cis) anhydrous milk fat American Oil Chemists’ Society active oxygen method ascorbyl palmitate behenic acid blackcurrant oil butterfat Federal Institute for Risk Assessment butylated hydroxyanisole butylated hydroxytoluene Brazil nut oil borage oil caffeic acid equivalent canola oil Centipoise cocoa butter cocoa butter equivalent cocoa butter improver coca butter replacement cardiovascular heart disease or coronary heart disease conjugated linoleic acid conjugated linolenic acid (18:3) coconut oil crude palm kernel oil crude palm oil cardiovascular disease days after flowering diacylglycerol(s) digalactosyl diglyceride docosahexenoic acid dimethylpolysiloxane deoxyribonucleic acid deterioration of bleachability index 1,1-diphenyl-2-picrylhydrazyl differential scanning calorimetery ethylenediaminetetraacetic acid

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List of Abbreviations

EPA EPO EU EU-27 FA FAC FAO FAS FDA FFA FFB FHSBO GC GE GG GHG GLA GLC GLCO GM HDL HEAR HLaCO HNO HO HOCO HOLLCO HOLLSOY HOSO HOSUN HP HL HP HO HPKS HPLC HPO HPOo HS HL HS HO HS HP HSCO HYDCO HYDSOY ICCA IEPO IOOC ISO IV L

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eicosapentaenoic acid; or Environmental Protection Agency evening primrose oil European Union 27 countries of the European Union fatty acid fatty acid composition Food and Agriculture Organisation Foreign Agricultural Service Food and Drug Administration (US) free fatty acids fresh fruit bunch fully hydrogenated soybean oil gas chromatography glycidol fatty acid esters galactosyl glycerol greenhouse gas(es) gamma-linolenic acid (18:3n-6, all cis) gas liquid chromatography gamma linolenic canola oil genetically modified or genetic modification high-density lipoprotein(s) high-erucic rapeseed oil high-lauric canola oil hazelnut oil high-oleic oil high-oleic canola oil high-oleic low-linolenic canola oil high-oleic low-linolenic soybean oil high-oleic sunflower oil high oleic sunflower oil high-palmitic/high-linoleic sunflower oil high-palmitic/high-oleic sunflower oil hydrogenated palm kernel stearin high-performance liquid chromatography hydrogenated palm oil hydrogenated palm olein high-stearic/high-linoleic sunflower oil high-stearic/high-oleic sunflower oil high-stearic/high-palmitic sunflower oil high-stearic canola oil hydrogenated canola oil hydrogenated soybean oil Interstate Cottonseed Crushers Association interesterified palm oil International Olive Oil Council International Standard Organisation iodine value linoleic acid

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List of Abbreviations

LCA LCPUFA LDL LEAR LFRA LLCO Ln LPC LPE M&I MAG MCF-7 MCFA MCPD MEOMA MGDG MNO MO MOSUN MPOB MPP MT mt MUFA NCPA NCVT NESHAP NSA NMR ND nr O O/L OOO OSI P PA PBSY PC PCR PDG PDI PDO PE PET PFAD PG PHSBO

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life-cycle analysis long-chain polyunsaturated fatty acids low-density lipoprotein low-erucic rapeseed oil Leatherhead Food Research Association (UK) low-linolenic canola oil linolenic acid lysophosphatidylcholines lysophosphatidylethanolamines moisture and impurities monoacylglycerol(s) human breast cancer cell line medium-chain fatty acid 3-monochloro-1,2-propanediol Malayan Edible Oil Manufacturers’ Association monogalactosyl diglycerol macadamia nut oil mid-oleic oil medium-oleic sunflower oil Malaysian Palm Oil Board dipalmitoyl myristoyl glycerol metric ton (tonne, 1000 Kg) million tonnes monounsaturated fatty acids National Cottonseed Products Association National Cotton Variety Trials National Emission Standards for Hazardous Air Pollutants National Sunflower Association (US) nuclear magnetic resonance non detectable not recorded oleic acid ratio of oleic acid to linoleic acid oleic-oleic-oleic triacylglycerol (triolein) oxidative stability index palmitic phosphatidic acids prime bleachable summer yellow (grade of cottonseed oil) phosphatidylcholines polymerase chain reaction palm diacylglycerols protein dispersibility index Protected Designations of Origin phosphatidylethanolamines polyethylene terephthalate palm fatty acid distillate phosphatidylglycerols; or propyl gallate partially hydrogenated soybean oil

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List of Abbreviations

PI PKO PKOo PKS PL PMF PO POME POO POo POP POs ppm PPP PPSt PS PV RBD RI RNAi RSO S SBDD SBO SCPA SDA SEP SFI SfMF SFO SG SMP snsn-1, sn-2 and sn-3 SOO SOS SPC SPI SSS St StOO StOSt SUS SUU SV TAG TBARS

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phosphatidylinositols palm kernel oil palm kernel olein palm kernel stearin phospholipids palm mid-fraction palm oil palm oil mill effluent dioleo palmitoyl glycerol (includes OPO isomer) palm olein dipalmitoyl oleoyl glycerol (includes PPO isomer) palm stearin parts per million (mg/kg) tripalmitoyl glycerol (triplamitin) dipalmitoyl stearoyl glycerol phosphatidylserines peroxide value refined, bleached and deodorised refractive index RNA interference (genetic technique used to interrupt the normal translation of mRNA molecules) rapeseed oil stearic; or saturated (type of fatty acid) soybean deodorizer distillate soybean oil Society of Cotton Products Analysts stearidonic acid (18:4n-3, all-cis) sequential extraction process solid fat index soft milkfat fraction sunflower oil esterified phytosterol glycoside; or specific gravity slip melting point stereospecific or regiospecific numbering positions of the glycerol backbone stearic-oleic-oleic triacylglycerol stearic-oleic-stearic triacylglycerol soy protein concentrates soy protein isolate trisaturated acyglycerols or trisaturates stearic acid stearic-oleic-oleic triacylglycerol stearic-oleic-stearic triacylglycerol disaturated monounsaturated acylglycerols diunsaturated monosaturated acylglycerols saponification value triacylglycerol(s) thiobarbituric acid-reactive substances

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List of Abbreviations

TBHQ TIU TRF tr U US USDA USDA–NASS VCO WHO WNO wt

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tertiary-butylhydroquinone trypsin inhibitor unit tocotrienol rich fraction trace unsaturated (type of fatty acid) unsaponifiable matter United States Department of Agriculture United State Department of Agriculture – National Agricultural Statistics Service virgin coconut oil World Health Organisation walnut oil weight

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1

Production and Trade of Vegetable Oils

Frank D. Gunstone

1.1 EXTRACTION, REFINING AND PROCESSING Most vegetable oils are obtained from beans or seeds, which generally furnish two valuable commodities: a fatty oil and a protein-rich meal. Seed extraction is achieved by pressing and/or by extraction with hexane. Oils such as palm and olive, on the other hand, are pressed out of the soft fruit (endosperm). Seeds give oils in differing proportions. Using USDA figures for 2008/09, world average oil yields are: soybean (18%), rapeseed (39%), sunflower (41%), groundnut (32%), cottonseed (14%), coconut (62%) and palmkernel (44%). In addition, yields from palm fruit (45–50%), olive (25–30%) and corn (about 5%) are as indicated. The relatively low yield of oil from soybeans is compensated for by the value of the highquality protein meal (79%) accompanying the oil. Some oils, such as virgin olive oil, are used without further treatment other than filtering, but most are refined in some measure before use. The refining processes remove undesirable materials (phospholipids, monoacylglycerols, diacylglycerols, free acids, colour and pigments, oxidised materials, flavour components, trace metals, sulphur compounds and pollutants), but may also remove valuable minor components, including antioxidants and vitamins such as carotenes and tocopherols. The refining processes must therefore be designed to maximise the removal of undesirable components and minimise the removal of the valuable minor components. Some of the latter are recovered from side streams of the refining process to give commercial products such as phospholipids, free acids, tocopherols, carotenes, sterols and squalene. Because of changes that occur during refining, it is important to know whether compositional data refer to crude or refined oil. Details of the levels of these in the various seed oils are given in appropriate chapters in this volume. Extraction processes have been described by Fils (2000), De Greyt and Kellens (2000) and, more recently, Dijkstra and Segers (2007). Hamm (2001) has discussed the major differences in extraction and refining procedures in Europe and North America as a consequence of the size of the industrial plant and of the differing oilseeds to be handled. With only a limited number of oils and fats available on a commercial scale, it is not surprising that on their own these are sometimes inadequate to meet the physical, chemical and nutritional properties required for use in food products. Over a century or more, lipid technologists have designed procedures for overcoming the limitation of having only a restricted range of natural products. In particular, they have sought to modify fatty acid and Vegetable Oils in Food Technology: Composition, Properties and Uses, Second Edition. Edited by Frank D. Gunstone. © 2011 Blackwell Publishing Ltd. Published 2011 by Blackwell Publishing Ltd.

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Vegetable Oils in Food Technology Table 1.1 Methods of changing fatty acid and triacylglycerol composition to modify physical, chemical and nutritional properties. Technological solutions Blending Distillation Fractionation Hydrogenation Interesterification with chemical catalysts Interesterification with specific lipases Enzymatic enhancement Biological solutions Domestication of wild crops Oils modified by conventional seed breeding Oils modified by (intra-species) genetic engineering Lipids from micro-organisms or other unconventional sources Source: Gunstone (2006).

triacylglycerol composition, knowing that such changes influence the important properties of food fats. These have been classified (Gunstone 2006) into technological and biological procedures such as those listed in Table 1.1. The procedures most relevant to this book are fractionation, hydrogenation and modification of fatty acid composition by conventional seed breeding or genetic engineering. Details are given in some of the following chapters. As an example, the usefulness of palm oil and palmkernel oil is greatly extended by fractionation. Hydrogenation may be applied in three ways. A very light hydrogenation (brush hydrogenation) applied to soybean oil or rapeseed oil will halve the level of linolenic acid and thereby increase oxidative stability (shelf-life). More extensive, but still partial, hydrogenation is applied to unsaturated liquid oils to produce semisolid fats that can be used as margarines and spreads. Through this process the levels of polyunsaturated fatty acids are markedly reduced, saturated acid content rises slightly, and there is a large rise in the levels of monounsaturated acids, much of it with trans configuration. The trans acids have higher melting points than their cis isomers, thereby contributing to the desired increase in solid acids. However, trans acids are now accepted as having undesirable nutritional properties and the food industry has revised procedures to limit their level. In some countries the level of trans acids has to be reported on the packaging and this increases the pressure to minimise the levels of these acids (Wilson 2009). Complete hydrogenation gives a product with virtually no unsaturated acids and therefore no trans acids. This is hardstock that can be blended with unsaturated oil, often before interesterification. In the following chapters examples are cited of where fatty acid composition has been modified by biological methods, both traditional and modern. Well-known examples include low-erucic acid rapeseed oil (canola oil), high-oleic sunflower oil and low-linolenic soybean oil, but attempts to develop oils with modified fatty acid composition and/or a changed composition of minor products such as tocopherols are being pursued actively in many countries. Some of these have been described (Gunstone 2007b; Watkins 2009) and others are cited in the following chapters of this book. Perhaps the most exciting of these are the attempts to produce long-chain polyunsaturated fatty acids such as eicosapentaenoic acid (20:5) and docosahexaenoic acid (22:6) in a field crop (Napier 2006). Following their introduction into commercial agriculture in 1996, genetically modified (GM) crops are now grown in many countries. Nevertheless, opposition to such crops

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remains in Europe and elsewhere and GM-free products are in demand (Section 1.3.8). This restriction also applies to minor products and it has sometimes been difficult to obtain GM-free lecithin (phospholipid), which comes mainly from soybean oil (Gunstone 2008c).

1.2 1.2.1

VEGETABLE OILS: PRODUCTION, CONSUMPTION AND TRADE Nine vegetable oils

Oils and fats are produced from animal and vegetable sources, with the former group declining in market share though not in production tonnage. Tallow, lard and butter still occupy the fifth, sixth and seventh positions after the four dominant vegetable oils (palm, soybean, rapeseed and sunflower seed). During the twentieth century the contribution of animal fats fell from 50% to 20% and in 2009 it was less than 16%, showing that vegetable fats have become increasingly dominant (Table 1.2). Statistical information about production, consumption and trade in oils and fats comes from two major sources. Oil World ISTA Mielke of Hamburg, Germany, is a market analyst producing weekly, monthly, annual and occasional reports on 10 oilseeds, 17 oils and fats (13 vegetable and 4 animal) and 10 oil meals. This valuable information has to be purchased. In contrast, information from the USDA is available free online and is updated each month (search for ‘USDA-FAS oilseeds’ in Google or any other search engine). However, this latter source does not include animal fats and covers only seven oilseeds (copra, which is the source of coconut oil, cottonseed, palmkernel, groundnut, rapeseed, soybean and sunflower seed), nine oils (from these seven oilseeds and from palm and olive) and eight oilmeals (from the seven oilseeds and from fish). The four additional vegetable oils covered by Oil World are corn, sesame, linseed and castor oils. These two sources of information show good but not perfect agreement. It is not easy for those who produce these reports to collect all the necessary data and figures continue to be subject to revision over several years. Figures in this chapter will come primarily from the USDA source and only occasionally from Oil World. This makes it easier for readers to consult the website themselves for up-to-date information. The nine vegetable oils can be classified in several ways. One categorisation recognises four major oils (palm, soybean, rapeseed and sunflower), two lauric oils (coconut and palmkernel, with a very different fatty acid composition from the other commodity oils) and the remaining oils (cottonseed, groundnut and olive). It is also useful to distinguish between oils and fats obtained from tree crops (coconut, palm and olive) and those from annual seed/bean crops, and also to recognise those that are

Table 1.2 Average annual production of total oils and fats and of animal fats (million tonnes and % of total) during the twentieth century. Years Oils and fats (17) Animal fats (mt) Animal fats (%)

1909/13

1936/39

1958/62

1976/80

1986/90

1996/2000

13.1 6.5 50

20.2 8.5 42

29.8 11.8 40

52.6 17.2 33

75.7 19.8 26

105.1 21.3 20

Source: Based on Mielke (2002) for 17 commodity oils and Hatje (1989).

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by-products. These are important factors in understanding the dynamics of production and trade. Trees have to be planted and mature, usually for many years, before they produce an economic crop. Yields from tree crops are influenced by climatic changes from season to season and by inputs such as fertiliser, pesticides, herbicides and irrigation, although crops will continue for many years (25–35 years for palm, around 100 years for olive). Annual crops (soybean, rapeseed, sunflower etc.), on the other hand, depend on planting decisions that farmers make each year based on agricultural and economic factors. These decisions result in changes in supply from year to year. For vegetable oils that are by-products, decisions on annual production depend on factors other than oil production. For example, cotton is grown according to the demand for fibre and not for cottonseed oil. Corn is not grown primarily for its oil and peanuts are grown as much for consumption as nuts as for oil production. It is also worthy of note that crushing soybeans produces two components – soybean oil (18%) and soybean meal (79%) – both of which are valuable commercial products. At different times the oil or the meal is in greater demand. Annual crops are produced at harvest time, which comes late in the calendar year in the northern hemisphere and early in the calendar year in the southern hemisphere. However, equatorial tree crops such as palm and coconut are harvested throughout the year, though there is some seasonal variation in quantity. Production data are often reported in harvest years such as 2008/09. These relate to 2008 harvests in the northern hemisphere and 2009 harvests in the southern hemisphere.

Table 1.3 Population (millions), production, exports, imports and total consumption (million tonnes) of seven oilseeds and nine vegetable oils in selected countries in 2008/09. Pop

World** China EU-27 India USA Indonesia Brazil Malaysia Pakistan Russia Japan Mexico Argentina Turkey Egypt

6829 1323 497 1198 315 230 194 27 181 141 127 110 40 75 83

Oilseeds*

Oils§

Prod

Exp†

Imp

Prod

Exp†

Imp

Consump

395.3 57.8

94.4 1.2

92.9 44.1 17.8

55.1

33.7 89.2

35.8

131.8 16.0 15.4 6.8 9.6 22.7

54.3 9.8 8.7 8.8 3.2

129.3 24.6 22.6 14.7 11.2 6.0 5.1 4.6 3.4 3.0 2.1 2.0 1.8 1.7 1.6

1.4 59.5

19.4

1.5 16.6 2.0 16.8

7.7

5.8

30.1

1.3 2.2

5.8 4.9 35.7

6.3 1.7 1.2

0.8 1.5

Source: USDA, December 2009. Notes: * Oilseeds are copra, cottonseed, palmkernel, peanut (groundnut), rapeseed, soybean and sunflowerseed. Oils also include palm and olive. ** The countries selected are the largest consumers of vegetable oils. § These figures cover oil extracted from both indigenous and imported seeds. † Canada (population 34 million) exported 10.0 million tonnes of seed and 1.6 million tonnes of oil. Ukraine (population 46 million) exported 3.7 million tonnes of seed and 2.2 million tonnes of oil.

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In discussing trade in oilseeds and oils in geographical terms, it is useful to recognise four types of countries/regions. These are discussed below and illustrated in Table 1.3. Population figures are in millions and relate to 2009. ●

●

●

●

Countries with small populations that produce large amounts of oilseeds/oils and are large exporters of these commodities. Examples are Australia (population 21 million), Malaysia (27 million), Canada (34 million), Argentina (40 million) and Ukraine (46 million). Countries with large populations that produce large amounts of oilseeds/oils and fats to feed their own populations but are still significant exporters. Examples are the USA (315 million), Indonesia (230 million) and Brazil (194 million). Countries with very large populations that are major importers despite local production. China (1323 million), India (1198 million) and other highly populated countries in Asia belong to this category. The Indian subcontinent of India, Pakistan (181 million), Bangladesh (162 million) and Sri Lanka (20 million) is a very large importer of vegetable oils. Finally there are countries/regions that are essentially traders. They produce, consume, import and export these commodities. The 27 countries of the European Union (EU-27) form the biggest example, but Hong Kong and Singapore are also significant traders by virtue of their geographical closeness to the world’s largest importer (China) and exporters (Indonesia and Malaysia).

Tables 1.4 and 1.5 show the annual production of nine vegetable oils between 1995/96 and 2008/09 (14 years). Total production of the nine oils rose from 71 to 133 million tonnes Table 1.4 Production (million tonnes) of nine vegetable oils during the period 1995/96 to 2008/09.

1995/96 1996/97 1997/98 1998/99 1999/2000 2000/01 2001/02 2002/03 2003/04 2004/05 2005/06 2006/07 2007/08 2008/09 Increase 1995/96 to 2001/02 Increase 2002/03 to 2008/09

9 oils

Palm

Soya

Rape

Sun

5 oils*

71.2 73.8 75.2 80.3 86.0 89.8 92.7 96.1 102.8 111.7 118.7 121.5 127.8 131.8

16.2 17.6 16.9 19.2 21.8 24.3 25.3 27.6 30.0 33.5 35.8 37.2 40.9 42.4

20.3 20.4 22.4 24.4 24.5 26.7 28.9 30.6 30.2 32.6 34.6 36.4 37.5 35.7

11.1 10.5 11.4 11.8 14.0 13.3 13.1 12.2 14.1 15.7 17.3 17.0 18.3 20.4

9.1 8.6 8.5 9.3 9.3 8.2 7.4 8.1 9.2 9.2 10.6 10.6 9.7 11.8

14.5 16.7 16.0 15.6 16.4 17.3 18.0 17.6 19.3 20.7 20.4 20.3 21.4 21.5

21.5

9.1

8.6

2.0

–1.7

3.5

35.7

14.8

5.1

8.2

3.7

3.9

Source: USDA, December 2009. Note: * Coconut, cottonseed, olive, palmkernel and peanut (groundnut) oils.

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Vegetable Oils in Food Technology Table 1.5 Four major vegetable oils as a percentage of vegetable oil production (9 oils) in the period 1995/96 to 2008/09. Oil Palm Soybean Rapeseed Sunflower seed Total

1995/96

2000/01

2005/06

2008/09

22.8 28.5 15.6 12.8 79.7

27.1 29.7 14.8 9.1 80.7

30.2 29.1 14.6 8.9 82.8

32.2 27.1 15.5 9.0 83.8

Note: Figures derived from Table 1.4.

Table 1.6 Production of 7 oilseeds, 9 oils and 8 oil meals (million tonnes) during the five-year period 2004/05 to 2008/09.

7 oilseeds* Crush Crush (%) 9 oils** 8 meals§

2004/05

2005/06

2006/07

2007/08

2008/09

381.5 302.8 79.4 111.5 207.0

391.4 318.8 81.4 118.7 216.5

404.2 328.4 81.2 121.5 224.3

391.8 338.3 86.3 127.8 230.9

385.3 338.2 87.8 131.8 228.5

Source: USDA, December 2009. Notes: * Copra, cotton, groundnut, palmkernel, rape, soy and sunflower. ** The 7 plus palm oil and olive oil. § The 7 plus fish meal (around 5 million tonnes).

(86%). Increases in palm (167%), soya (76%), rape (82%), sunflower (25%) and the remaining five oils (49%) were at the levels indicated in parentheses. The four oils increasingly dominate vegetable oil production at a total proportion exceeding 80% and rising. Annual production of nine vegetable oils in 2008/09 was expected to be about 133 million tonnes. Given an average price of around $800 per tonne, this gives a total value of over $1000–1100 billion for the year’s vegetable oil production. In Tables 1.6, 1.7 and 1.8 attention is focused on the five years 2004/05 to 2008/09 to show the most recent trends. Oils and fats come from oilseeds, fruits and from animal sources and Table 1.6 gives figures for seven oilseeds. Most of the seed is crushed to produce oil and meal, but some is held back as seed for planting and some is used directly for animal feed or human food. The proportion of these varies slightly from year to year, depending on the relative amounts of the various oilseeds with their different levels of oil. The term ‘consumption’ needs explanation. Applied to a country/region for a particular year, it is the sum of local production and imports minus exports and allowance for changes in stocks for the year in question. It applies to consumption for all purposes, including human food, animal feed, industrial consumption and waste, and cannot be equated with dietary intake. The term ‘human consumption’ in these tables refers to the consumption of nine vegetable oils and does not allow for other sources of dietary fat such as animal fats, fat from meat and nuts and so on. Consumption of these vegetable oils (for all purposes) per person is expressed in kg/year and is available on a global basis (as in Table 1.8) or for

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Table 1.7 Production (million tonnes) of 9 individual vegetable oils during the five-year period 2004/05 to 2008/09.

Total Palm Soybean Rapeseed Sunflower Groundnut Palmkernel Cottonseed Coconut Olive

2004/05

2005/06

2006/07

2007/08

2008/09

111.47 33.53 32.60 15.72 9.18 5.08 4.15 4.78 3.46 2.96

118.72 35.83 34.62 17.30 10.60 4.97 4.40 4.90 3.47 2.66

121.50 37.23 36.36 17.01 10.61 4.51 4.48 5.13 3.26 2.91

127.82 40.94 37.55 18.31 9.67 4.90 4.90 5.22 3.49 2.84

131.81 42.40 35.72 20.38 11.83 5.00 5.13 4.84 3.55 2.97

Source: USDA, December 2009. Notes: Vegetable oils listed in decreasing order of production in 2008/09. Forecast for 2009/10: total (137.3), palm (45.1), soybean (37.7) and sunflower (11.4).

Table 1.8 Production, consumption, exports and imports (million tonnes) of 9 vegetable oils during the five-year period 2004/05 to 2008/09.

Production Consumption Per person (kg/y) Exports Imports Population (billion)

2004/05

2005/06

2006/07

2007/08

2008/09

111.5 107.9 16.8 42.4 40.5 6.44

118.7 115.5 17.7 47.6 44.7 6.51

121.5 120.9 18.4 49.0 48.0 6.59

127.8 125.4 18.8 53.5 50.5 6.67

131.8 129.3 19.2 53.1 54.3 6.75

Source: USDA, December 2009.

individual countries/regions. This figure has shown a steady rise over many years. In the years between 2004/05 and 2008/09, it rose 15% from 16.8 to 19.3 kg/year. These are average values and vary considerably between countries. Values are much above this average in Europe and North America and below it in many African and Asian countries. Exports and imports are virtually the same and correspond to almost 40% of total production. The balance is used in the country where it is produced. There is also a trade in oilseeds, particularly of soybeans from North and South America to China and elsewhere (Sections 1.3.1 and 1.3.2). In Tables 1.9, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16 and 1.17, attention is directed to the production, consumption and imports/exports of the vegetable oils described in the other chapters of this book. Each table shows the major countries/regions involved. The figures in the following text apply to the year 2008/09. They vary slightly from year to year, but the major trends are unlikely to change very quickly. Readers can use the USDAFAS website to get up-to-date information. Some major points from each table are discussed here, and readers can derive further information through careful study of the tables and the appropriate chapters for each vegetable oil.

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Table 1.9 Palm oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09. Total*

Major countries/regions

Production Consumption Total

42.40

Indonesia 19.5, Malaysia 17.3, Thailand 12, Nigeria 0.8, Colombia 0.7

41.65

India 6.5, China 5.6, Indonesia 4.9, EU-27 4.6, Malaysia 2.6, Pakistan 2.2, Nigeria 1.2, USA 1.0, Thailand 0.9, Bangladesh 0.7, Egypt 0.7

Food Industrial Other Exports Imports

32.61 8.31 0.73 34.23 34.07

Malaysia 16.0, Indonesia 14.6 India 6.9, China 6.1, EU-27 4.9, Pakistan 2.2, USA 1.0, Bangladesh 0.7

Source: USDA, December 2009. Note: * Figures in the first edition of this book (2000/01) were 23.38 (production), 23.20 (consumption), 16.75 (exports) and 16.64 (imports) million tonnes. These numbers indicate increases of 81%, 80%, 104% and 105% respectively.

1.2.2

Palm oil

Palm oil has long been the oil traded (imported/exported) in the greatest quantity (31 million tonnes). It is now also the oil produced in the greatest amount (43 million tonnes) and continues its steady growth. Figures in Table 1.9 show that in the 14 years between 1995/96 and 2008/09 palm oil production increased by 2.7-fold. Production and exports of this oil are dominated by two South East Asian countries. In 2008/09 Indonesia was responsible for 46% and 47% of global palm oil production and exports respectively; for Malaysia these figures were 41% and 45% respectively. Other countries in this region and in Africa and South America are trying to develop oil palm plantations, often with the assistance of Malaysian capital and Malaysian expertise, although the volumes produced remain small. The minor palm oil-producing countries include (in declining order) Thailand, Nigeria, Colombia, Ecuador and Papua New Guinea, with production levels between 1.4 and 0.4 million tonnes. Palm oil is consumed in many countries and it has been important in meeting the rapidly growing demand for vegetable oils in developing countries, with their increasing populations and increasing personal income. The main importers are now India (20% of total palm oil exports), China (18%) and EU-27 (14%). The Indian subcontinent (India, Pakistan and Bangladesh) accounts for 30% of total imports. USDA numbers (Figure 1.1) show that an increasing proportion of palm oil is being used for non-food purposes, including biodiesel production. Between 1995/96 and 2001/02 3–4 million tonnes of palm oil was used for non-food purposes. By 2008/09 this had risen to almost 10 million tonnes (Table 1.9). This change pre-dates large-scale production of biodiesel from palm oil and probably reflects the increasing use of palm oil in the oleochemical industry as an alternative to tallow, following the growth of the oleochemical industry in Malaysia.

1.2.3

Soybean oil

Soybean oil (Table 1.10) is the oil produced in the second largest amount after palm oil. In addition to the trade in soybean oil, there is a strong trade in beans. Although there is some closure of the gap between palm and soybean oil, if exported beans are considered in terms

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Palm oil

50 45

Million tonnes

40 35 Total Food Non-food

30 25 20 15 10 5

/0 9 20

08

/0 7 06

/0 5 20

04 20

02

/0 3

/0 1 20

00 20

/9 9 98 19

19

96

/9 7

0

Year Figure 1.1 Consumption of palm oil (million tonnes) from 1996/97 to 2008/09 divided between food and non-food uses. Source: USDA, December 2009. Note: Non-food uses include animal feed, oleochemicals and biodiesel.

Table 1.10 Soybean oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Exports Imports

Total*

Major countries/regions

35.71 35.68 9.01 8.87

USA 8.50, China 7.31, Argentina 6.12, Brazil 6.02, EU-27 2.31, India 1.34 China 9.49, USA 7.43, Brazil 4.27, EU-27 2.80, India 2.33, Argentina 1.40 Argentina 4.67, Brazil 1.91, USA 0.99 China 2.49, India 1.06, EU-27 0.82

Source: USDA, December 2009. Notes: There is also significant trade in soybeans. * Figures in the first edition of this book (2000/01) were 26.66 (production), 26.65 (consumption), 7.45 (exports) and 7.44 (imports) million tonnes. These numbers indicate increases of 34%, 34%, 21% and 19% respectively.

of their oil equivalent, palm oil trade still exceeds that of soybean oil. There is no comparable trade in palm fruits, since these must be extracted as soon possible after harvesting and as close as possible to the place of harvesting. The major producers of soybean oil are the USA, Brazil, Argentina, China (local beans augmented with imports) and EU-27 (using mainly imported beans). Soybean is consumed in every country for which details are available. Consumption is greatest in the producing countries, with six countries/regions each exceeding one million tonnes. These are China (27% of world consumption), USA (21%), Brazil (12%), EU-27 (8%), India (6%) and Argentina (4%). Argentina is now the largest exporter of soybean oil

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(4.7 million tonnes, 52% of total soybean oil exports). Many countries import soybean oil, with China (28% of world imports) being dominant in 2008/09. The USDA does not provide figures for the industrial use of soybean oil, but the Soy Stats website reports that in 2008 in the USA 1.55 million tonnes (18% of the total of 8.43 million tonnes) was used for industrial purposes. This included 2612 million litres of biodiesel (equivalent to 2.3 million tonnes of source material, which is mainly but not entirely soybean oil). Figures for 2006 and 2007 biodiesel production were 946 and 1713 million litres respectively. It seems likely that a smaller proportion of soybean oil is used for industrial purposes in other countries, though there is now a considerable and growing production of biodiesel in Argentina and Brazil. For 2009 this figure is over 1 million tonnes in each country, produced mainly, but not entirely, from soybean oil (see Table 1.21). Most (85–90%) of the soybeans grown in the USA are now obtained from GM seeds and non-GM soybean oil is only available from identity-preserved beans. Sourcing non-GM lecithin from non-GM beans has provided some challenges. Soybean oil from Argentina and from Brazil also comes mainly and increasingly from GM seeds (ISAAA, Soy Stats and Soya Tech websites). Those countries that are concerned about vegetable oils from GM seeds are worried not only about the supply of soybean oil but also of the minor products (lecithin, tocopherols, sterols) from this source.

1.2.4

Rapeseed/canola oil

Rapeseed/canola oil (Table 1.11) now occupies the third position in rank order of production of oils and fats after palm and soybean oils (Table 1.4). EU-27, China and India dominate production and consumption of this oil, and Canada, with its relatively small population (34 million), is an important grower and exporter of seed. Since the first edition of this book there has been a marked change in the non-food use of this oil, related particularly to its use in Europe as the dominant source of biodiesel (Table 1.21). The plot in Figure 1.2 shows a change starting in 2003/04. In the period up to 2002/03 non-food consumption of rapeseed oil was about 1 million tonnes (0.9–1.3, 5–10% of total production). Over the last six years non-food consumption has risen to 6 million tonnes (now around 30%), while food consumption has also risen but only from 13 to 14 tonnes

Table 1.11 Rapeseed oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Total Food Non-food Exports Imports

Total*

Major countries/regions

20.38

EU-27 8.42, China 4.70, India 2.06, Canada 1.78, Japan 0.88

19.92 13.97 5.95 2.37 2.44

EU-27 8.54, China 4.85, India 2.05, Japan 0.92, Canada 0.35

Canada 1.53 EU-27 0.45, China 0.45

Source: USDA, December 2009. Notes: There is also significant trade in seed. * Figures in the first edition of this book (2000/01) were 14.15 (production), 14.28 (consumption), 1.65 (exports) and 1.64 (imports) million tonnes. These numbers indicate increases of 44%, 39%, 44% and 49% respectively.

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Rapeseed oil 25.00

Million tonnes

20.00

Total Food Non-food

15.00 10.00 5.00

/0 9 08

/0 7

20

06 20

04

/0 5

/0 3 20

02

20

00

/0 1

/9 9 20

98

19

19

96

/9 7

0.00

Year Figure 1.2 Consumption of rapeseed oil (million tonnes) from 1996/97 to 2008/09 divided between food and non-food uses. Source: USDA, December 2009. Note: Non-food uses include animal feed, oleochemicals and biodiesel.

Table 1.12 Sunflower oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Exports Imports

Total*

Major countries/regions

11.83 10.83 4.59 4.04

Russia 2.56, Ukraine 2.63, EU-27 2.33, Argentina 1.52, Turkey 0.51 EU-27 3.19, Russia 1.92, Turkey 0.79, Argentina 0.38, Ukraine 0.36, Ukraine 2.10, Argentina 1.10, Russia 0.80 EU-27 1.05, Turkey 0.43

Source: USDA, December 2009. Notes: There is also trade in seeds. * Figures in the first edition of this book (2000/01) were 8.87 (production), 9.17 (consumption), 2.37 (exports) and 2.39 (imports) million tonnes. These numbers indicate increases of 33%, 18%, 94% and 69% respectively.

(Table 1.19). It appears that most of the additional production of rapeseed oil in the last six years has gone into non-food uses.

1.2.5

Sunflowerseed oil

Sunflowerseed oil (Table 1.12) is the last member of the group of four major vegetable oils. It maintains its share at about 9% of total vegetable oils, although it has achieved variable levels over recent years (Tables 1.4 and 1.5). It is available in forms that vary markedly in fatty acid composition (see Chapter 5), but these are taken together in the data presented here. Production is mainly in the area covered by Russia, Ukraine, Turkey and adjoining countries in Europe. It is also grown in Argentina.

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12

Vegetable Oils in Food Technology Table 1.13 Groundnut oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Exports Imports

Total*

Major countries/regions

5.00 4.86 0.19 0.16

China 2.17, India 1.54 China 2.18, India 1.42 EU-27 0.10, USA 0.02

Source: USDA, December 2009. Note: * Figures in the first edition of this book (2000/01) were 4.86 (production) and 4.87 (consumption) million tonnes. These numbers indicate increases of only 4% and 0% respectively.

Table 1.14 Cottonseed oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Exports Imports

Total*

Major countries/regions

4.83 4.79 0.19 0.07

China 1.60, India 1.03, USA 0.30 China 1.59, India 1.04 USA 0.22 USA 0.09

Source: USDA, December 2009. Note: * Figures in the first edition of this book (2000/01) were 3.89 (production) and 3.94 (consumption) million tonnes. These numbers indicate increases of 24% and 22% respectively.

1.2.6

Groundnut (peanut) oil

Only about 46% of groundnuts are crushed, most of the balance being consumed as nuts. There is very little trade in the oil. It is produced and used mainly in China and India, which together account for around 74% of both total production and consumption (Table 1.13). Minor quantities of the oil are produced and used in African countries.

1.2.7

Cottonseed oil

Cottonseed oil (Table 1.14) is another oil traded only to a small extent. China is the major producer and consumer (almost one third of the total), with India, the USA, the former Soviet Union, Pakistan, Brazil and Turkey producing lower levels. This crop is grown for its fibre, with the seed oil as a by-product.

1.2.8

Coconut oil

Coconut oil (Table 1.15) has had a very uneven record in terms of its production as a consequence of climatic and political instability in the countries where it is produced. Production at 3–4 million tonnes is mainly in the Philippines, Indonesia and India. The Philippines and Indonesia are major exporters, while the EU-27 and the USA are major importers. Coconut

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Production and Trade of Vegetable Oils

13

Table 1.15 Coconut oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Total Food Industrial Exports Imports

Total*

Major countries/regions

3.55

Philippines, Indonesia, India

3.37 1.82 1.51 1.66 1.61

EU-27, USA, India, Philippines

Philippines, Indonesia EU-27, USA, Malaysia

Source: USDA, December 2009. Note: * Figures in the first edition of this book (2000/01) were 3.43 (production), 3.30 (consumption), 2.05 (exports) and 2.09 (imports) million tonnes. These numbers indicate increases of only 3% and 2% for production and consumption respectively. Imports and exports have declined. In contrast, the other lauric oil (palmkernel) has risen steadily along with palm oil production and now exceeds coconut oil.

Table 1.16 Palmkernel oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09.

Production Consumption Exports Imports

Total*

Major countries/regions

5.13 5.28 2.18 2.42

Malaysia, Indonesia Malaysia, EU-27, China, USA Indonesia, Malaysia EU-27, USA, Malaysia

Source: USDA, December 2009. Note: * Figures in the first edition of this book (2000/01) were 2.89 (production), 2.81 (consumption), 1.43 (exports) and 1.42 (imports) million tonnes. These numbers indicate increases of 78%, 88%, 52% and 70% respectively and parallel the changes for palm oil.

is an important lauric oil used about equally by the food and oleochemical industries. It competes with palmkernel oil as the other major lauric oil.

1.2.9

Palmkernel oil

Palmkernel oil (Table 1.16) is produced along with palm oil from the oil palm and has shared in the rapid growth of the latter commodity. Production levels now exceed those of coconut oil. Malaysia and Indonesia are major producing countries, with the EU-27 and USA being major importing countries/regions. As with coconut oil, consumption is divided roughly equally between food and non-food uses.

1.2.10 Olive oil Olive oil (Table 1.17), produced at a level of around 3 million tonnes, has a long history going back to biblical times. It is produced and consumed in several Mediterranean countries. Small quantities are produced in Australia and New Zealand and in California. It is sold as a premium oil with strong marketing and is a component of the healthy Mediterranean lifestyle.

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14

Vegetable Oils in Food Technology Table 1.17 Olive oil: Major countries/regions involved in production, consumption and trade (million tonnes) in 2008/09. Total* Production Consumption Exports Imports

2.97 2.95 0.68 0.59

Major countries/regions EU-27 2.25, Turkey 0.17 EU-27 2.06, USA 0.27, Turkey 0.12 EU-27 0.41 USA 0.28, EU-27 0.15

Source: USDA, December 2009. Note: * Figures in the first edition of this book (2000/01) were 2.56 (production), 2,70 (consumption), 0.55 (exports) and 0.55 (imports) million tonnes. These numbers indicate increases of only 16%, 9%, 24% and 7% respectively.

1.2.11 Corn oil Corn oil is not included in the USDA figures. It was produced at levels around 2.4 million tonnes in 2008/09. In 2000/01 this figure was 2.0 million tonnes. About half of this comes from the USA, with China being the second largest producer. Imports and exports total about 0.7 million tonnes, with the USA the largest exporter and Turkey and Saudi Arabia the largest importers.

1.2.12 Sesame oil Sesame oil is not included in the USDA figures. It was produced at levels around 0.85 million tonnes in 2008/09. In 2000/01 this figure was 0.78 million tonnes. Production is mainly in China, Myanmar (Burma) and India and the oil is consumed mainly in the same three countries. There is only a limited trade in both oilseeds and oil.

1.2.13 Linseed oil Linseed oil is not included in the USDA figures. The seed (2–3 million tonnes) is grown mainly in Canada, China and India. Canada remains the largest grower, although production has declined in recent years. The oil (around 0.7 million tonnes) is produced mainly in the EU-27, China and the USA, using seed imported from Canada where necessary. There is very little trade in the oil.

1.3 1.3.1

SOME TOPICAL ISSUES Imports into China and India

The demand for vegetable oils and animal protein has increased steadily over many years, through increases in population but more through increases in income and in urbanisation. The increase in animal protein leads to a rising demand for seed meal, sourced mainly from oilseeds in general and from soybean in particular. Table 1.18 shows the increased consumption in China and in India in the past five years. Although both of these highly populated countries are significant producers of oilseeds, local production is insufficient to meet the growing indigenous demand. In China the gap has been met in part by extraction of imported

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Production and Trade of Vegetable Oils

15

Table 1.18 Consumption and imports (million tonnes) for China and India during the five-year period 2004/05 to 2008/09. 2004/05 China (population Oilseeds Production Imports Crush seeds

2005/06

2006/07

2007/08

2008/09

in 2009 1.32 billion) 58.35 26.12 60.54

56.80 29.00 64.97

55.23 29.70 65.28

53.35 38.64 68.47

57.80 44.14 72.88

13.81 6.69 20.53

14.76 6.96 21.51

14.27 8.50 22.56

14.69 8.76 23.34

16.02 9.77 24.65

India (population in 2009 1.20 billion) Oilseeds Production 29.40 30.70 Crush seeds 23.57 25.10

29.92 24.62

33.95 27.56

33.70 26.44

Vegetable oils Production Imports Consumption

6.43 5.44 11.91

7.01 5.91 12.96

6.80 8.79 14.73

Vegetable oils Production Imports Consumption

6.47 5.68 11.56

6.85 4.86 12.11

Source: USDA. Note: In 2008/09 world consumption of vegetable oils was 129 million tonnes and imports of oilseeds and of vegetable oils were 93 and 54 million tonnes respectively.

soybeans and rapeseed, providing both oil and meal, but the country still needs to import about one third of its vegetable oil consumption as palm and soybean oils (Tables 1.8 and 1.9). India imports increasing amounts of palm oil to meet its shortfall between consumption and local production (Table 1.9).

1.3.2

Trade in oilseeds and in vegetable oils

This book is devoted to vegetable oils and in this chapter information on the production, consumption and trade (imports and exports) is presented and discussed. For palm, olive and corn oils, these data give a good picture of the situation, but for oils extracted from seeds the picture is incomplete. There is considerable trade in oilseeds as well as in extracted oils. While it is not appropriate to give a full picture of oilseed movements here, trade in vegetable oils cannot be fully understood without attention to trade in oilseeds (Gunstone 2010a).

1.3.3

Food and non-food use of vegetable oils

This book is concerned with the source and composition of vegetable oils used in the food industry, but it must not be forgotten that a small but increasing share of vegetable oils is used in the oleochemical industry. Those most used for this purpose are the two lauric oils (coconut and palmkernel), palm (especially palm stearin) and linseed, along with castor oil (and tallow), although most vegetable oils find some oleochemical use. This includes the relatively new demand for biodiesel, which is usually the methyl esters of a readily available oil. This will be soybean (or tallow) in the USA and in South

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16

Vegetable Oils in Food Technology

Table 1.19 Total consumption and non-food use (million tonnes) of selected vegetable oils in 1999/2000 and 2008/09. Total consumption

1999/2000 2008/09

Non-food use*

Veg. oils**

Palm

Rape

Laurics§

Other†

Veg. oils**

Palm

Rape

Laurics§

Other†

82.7 129.3

20.5 41.6

13.7 19.9

5.6 8.7

42.9 59.1

8.1 26.1

3.1 9.0

0.7 6.0

2.8 4.3

1.5 6.8

Source: Based on USDA, December 2009. See also Gunstone 2009. Notes: * Non-food uses include oils fed to animals, those used in the traditional oleochemical industries, and those now used to produce biodiesel. The figures for non-food use are obtained by subtracting food consumption from total consumption. Figures for food use can be recovered from those provided in the table. ** Vegetable oils are the total for 9 oils. In addition to those listed in the table they include cottonseed, groundnut (peanut), olive, soybean and sunflower. § The lauric oils are coconut oil and palmkernel oil. In the absence of other information it is assumed that equal quantities of the lauric oils are used in food and non-food products. † The figures for ‘other’ are calculated from the remaining figures. The non-food figures for ‘other’ will relate mainly to soybean oil, as there is only a limited non-food use of cottonseed, groundnut (peanut), olive and sunflower oils.

America, rapeseed oil in Europe, palm oil in Malaysia and Indonesia, coconut in the Philippines and waste frying oil in Japan and elsewhere. Data given in Table 1.19 show how the non-food use of nine major vegetable oils has doubled from around 10% in the 1990s to around 20% in 2008/09. The USDA does not provide figures for the industrial use of soybean oil but the Soy Stats web site (accessed November 2010) reports that in 2009 in the USA 1 million tonnes (13% of the total of 7.41 million tonnes) was used for industrial purposes. This included 2063 million litres of biodiesel (equivalent to 1.8 million tonnes of source material, which is not entirely soybean oil). Figures for 2006, 2007 and 2008 biodiesel production were 848, 1893 and 2618 million litres respectively. It seems likely that a smaller proportion of soybean oil is used for industrial purposes in other countries, though there is now a considerable and growing production of biodiesel in Argentina and Brazil. For 2009 this figure is over 1 million tonnes in each country, produced mainly, but not entirely, from soybean oil (see also Table 1.21).

1.3.4

Prices

In the 10-year period 1998/99 to 2007/08, the average price of palm ($478/tonne in Malaysia) and of soya ($597), canola ($662), sunflower ($707) and coconut oil ($632) in Rotterdam, were as indicated in parentheses. As these figures show, palm oil is usually the cheapest and sunflower the most expensive of these vegetable oils. At the beginning of this period soybean oil and canola were comparable in price, but the demand for rapeseed oil for biodiesel has pushed the price of this oil above that of soybean oil. Average prices of these five oils for each year, plotted in Figure 1.3, show how the prices follow each other from year to year but with marked changes in price levels during the 12-year period covered in the graph. Palm oil, for example, ranged in price from $235/tonne in 2000/01 to $1058 in 2007/08. These changes are even more marked using monthly rather than annual figures. During 2007/08, palm ($1291 in March), soya ($1537 in June), canola ($1577 in June), sunflower ($2045 in June) and coconut ($1824 in May) had peak prices at the level and month shown in parentheses. It is apparent from Figure 1.3 that over the 12 years prices have fallen, risen, stayed level, risen sharply and then fallen back to the previously high values reached two years earlier. This price information comes from USDA

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Production and Trade of Vegetable Oils

17

Vegetable oil prices

1800 1600

US dollars/tonne

1400 1200

Palm Mal Soya Rott

1000

Canola Rott 800

Sun Rott

600

Coco Rott

400 200

2008/09

2007/08

2006/07

2004/05

2005/06

2003/04

2002/03

2001/02

2000/01

1999/00

1998/99

0

Year Figure 1.3 Prices of selected vegetable oils (US$/tonne) in Rotterdam or Malaysia during the 11 years 1998/99 to 2008/09. Source: USDA, December 2009.

figures of March and December 2009. Readers who want more recent information should go to the newest USDA-FAS figures. Rising prices are a consequence of the mismatch between supply and demand, which are themselves influenced by the following factors: ●

●

●

●

Gunstone_c01.indd 17

Growing food demand from a rising population with increasing wealth has been estimated at 4–5 million tonnes extra each year. Because of the world recession demand may have been at the lower end of this range in 2009. Demand for biodiesel, increasing at around 3 million tonnes per year, is mainly sourced from rapeseed oil and soybean oil, but not all of it comes from the major vegetable oils. Palm biodiesel is expected to become more important in the future and there are also other sources that are outside the usual listings of commodity oils, such as used frying oils, oils from new vegetable sources such as jatropha, and algal oil. There has been a great deal of investigation of these last two sources, but the final product is only now beginning to appear in small quantities. Eventually these will relieve the pressure on food oils. Furthermore, the availability of biodiesel will be affected by extremely high or low prices for mineral oil and for vegetable oils (see Table 1.21). The growing demands for food and biodiesel at about 7–8 million tonnes (with provisos set out above) are to be compared with annual increases in production in recent years of 4–9 million tonnes. Production levels in 2008/09 were expected to be 133 million tonnes for the nine major vegetable oils and a further 24 million tonnes for four animal fats. There has been an increase in the cost of agricultural production (fertilisers and pesticides are more expensive) and of storage and transport, all resulting from the considerable rise in the price of oil.

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18 ●

●

Vegetable Oils in Food Technology

Oilseed yields have fallen through poor climatic conditions in many parts of the world. For example, in recent years there have been droughts in Europe, Australia, Indonesia, Ukraine, south west Russia and China. Whenever there are substantial increases in prices, speculators interfere in the market, pushing up prices and making profits for themselves.

All this suggests that biodiesel production is only one of several factors driving prices upwards. Not everyone regards high vegetable oil prices as an unmitigated disaster, however. The commodity analyst Dorab Mistry of Godrej International in India spoke in support of high vegetable oil prices in 2007 (Mistry, 2007). Talking perhaps from an Indian viewpoint, he reminded his hearers that agricultural commodities have declined in real terms during the last 50 years and that as a consequence young people do not want to follow their parents into farming, so agriculture fails in the scramble for talent. He argued that higher prices for agricultural commodities are the fastest way to end rural poverty and have the highest multiplier effect for job creation and economic expansion in the economy. Low prices keep farmers poor, but higher growth in rural communities translates into higher growth for the economy as a whole and benefits everyone. He claimed that high prices for cereals and oilseeds are related to rapidly rising demand in the developing world at the same time as climatic conditions have reduced supplies in several parts of the world through recent droughts. Demand for biofuel is a further factor, although it is not the only reason for present high prices. At the time of writing the position is confused and the outlook uncertain. The price of mineral oil fell from its peak level in July 2008 of almost US$150 a barrel to levels between 30% and 40% of the maximum by the end of 2008, but then rose to around US$70. This volatility in price makes planning and development of future supplies very difficult. Vegetable oil prices have also dropped from the exceedingly high levels of the 2007/08 harvest year, but it is not clear at what levels these will settle (Figure 1.3). The demand for biofuels comes mainly from the developed world for environmental and political reasons, while the effect of high prices is felt most by the poor of Asia and Africa. Some of the poorer producing countries have introduced export tariffs on vegetable oils to keep sufficient supplies to feed their own people. Others, such as India, have decreed that biodiesel cannot be made from food-quality oils and fats. Presumably this restriction has been extended to the use of land that can grow food crops. This has led to the development of non-food crops such as jatropha and pongamnia, though the effects of these changes are not yet significant. The consequence of the below-peak prices is not clear. Accessibility by the poor for food use may increase, but the reduced cost also makes biodiesel production more viable. Furthermore, the changing price of mineral oil has an effect on biodiesel demand, though it has to be remembered that this last is often related to national mandate rather than to economic viability. The fall in income in the developed and the developing world during 2008 and later years is likely to reduce demand for vegetable oils, but it is too early to assess the level of this. Changing prices for vegetable oils can be considered over various time scales. In line with other agricultural commodities there has been a general decline in prices over 50 or more years of around 3% a year, so that prices have halved in real terms each 20–25 years. However, in the more recent past there have been violent fluctuations in both directions. For example, the very low prices being registered at the turn of the century were in marked contrast to the very high prices obtained more recently, though these have been falling since mid-2008 (Figure 1.3).

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1.3.5

19

The food–fuel debate

Two issues have come together to produce the food–fuel debate for oils and fats. One is the rise in prices for these commodities in recent years (Section 1.3.4) and the consequence of this, particularly for the poorer members of the world community. The other is the growing competition for commodities that can be used for food or fuels. This debate is related to supply and demand for both food and non-food purposes (Table 1.19). In this section the following topics will be discussed: ● ● ● ● ● ●

population changes; growing demand for food purposes; growing demand for non-food purposes, particularly biodiesel; increasing supply; reasons for changing prices; food vs fuel.

According to Evans (1998) the world population grew to one billion by 1825 and then passed through 2 billion (1927), 3 billion (1960), 4 billion (1975), 5 billion (1986) and 6 billion (1999). This means that those now in their 80s have seen the population treble in their lifetime and those approaching 50 have seen it double. It is expected that by 2050 the population will be around 9.4 billion, but that it will probably not increase much beyond that figure. To feed that number of people, Evans indicates that two problems have to be solved: we need to develop the global capacity to feed another 3 billion people and also to eliminate poverty and provide the health and education that would allow the poor to obtain food. Evans argues that agricultural science and technology should be able to address the first problem through six activities: (i) increase the area of land under cultivation; (ii) increase the crop yield per hectare of cultivation; (iii) increase the number of crops per hectare per year; (iv) displace lower-yielding crops by higher-yielding ones; (v) reduce post-harvest losses; and (vi) reduce the use of crops as feed for animals. All this has to be achieved without impoverishment of the soil and without excessive demand on water supplies. On the basis of the figures in Table 1.20, the population at present is increasing by about 800 000 each year and this raises the demand for oils and fats by about 1.3 million tonnes merely to maintain present consumption levels (Gunstone 2008a, b). However, not only is the population increasing in number. There is increasing wealth and increasing urbanisation, both of which raise the food demand for oils and fats and for meat (and therefore for seed meal required for animal feed). It is more difficult to estimate demand arising from these factors. In the 1980s the market analysts at Oil World considered that demand from increasing income was twice as large as that from increasing numbers, but the author of this chapter considers that in the light of rapid changes in China and India and other developing countries, this factor is probably closer to three (Gunstone 2008b). This suggests an increasing demand for food purposes of about 5 million tonnes each year. Since around the 1980s it has been accepted that 17 commodity oils and fats are used for human food, animal feed (in addition to seeds used directly as animal feed) and for the oleochemical industry (producing soap and other surface-active compounds, glycerol and for use in paints and so on) in a ratio of approximately 80:6:14. With the new demand for biodiesel this is more likely to be 74:6:20 today and figures of 68:6:26 have been suggested for 2020 (Gunstone 2007a). These changing ratios indicate that a lower

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20

Vegetable Oils in Food Technology Table 1.20 Oil and fat production, population and average use (for all purposes) since 1976. Year

Production

Population

Average

million tonnes

billions

kg/person/yr

Five-year averages 1976–80 52.7 1981–85 63.1 1986–90 75.7 1991–95 86.8 1996–2000 105.1

4.28 4.66 5.08 5.50 5.90

12.3 13.5 14.9 15.8 17.8

Individual years 2000 114.7 2001 117.6 2002 120.5 2003 124.8 2004 132.4 2005 141.1 2006 150.0 2007 154.1 2008 159.7

6.07 6.15 6.22 6.30 6.43 6.51 6.59 6.67 6.75

18.8 19.1 19.3 19.8 20.6 21.7 22.8 23.1 23.7

Sources: Mielke (2002, 2004, 2009).

proportion of oils and fats will be available for human food, but not a lower amount because of the increasing supply (see below). There is no doubt that things are changing at the margin. Gunstone (2007a) compared data for two seven-year periods, 1993/94 to 1999/2000 and 1999/2000 to 2006/07, in respect of the nine major vegetable oils. In the first seven-year period an increase of 21.2 million tonnes was split between greater food use (19.7 million tonnes) and non-food use (up 1.5 million tonnes). In the more recent seven-year period an increase of 39.2 million tonnes was split between these two categories at levels of 24.5 and 14.7 million tonnes. There has clearly between a shift towards non-food use. This is mainly apparent in palm oil (non-food use up 6.9 million tonnes) and rapeseed oil (up 4.2 million tonnes), as shown in Figures 1.1 and 1.2. Similar figures for other years are given in Table 1.19. In considering these ratios it has to be noted that different figures are obtained when considering only nine vegetable oils from those when the animal fats and some minor vegetable oils are included (17 oils and fats). Demand for biodiesel can be assessed at three levels: that required by national mandates at specified dates in the future, that indicated by the size and number of biodiesel plants being commissioned, and that reported as production levels. The last is the most realistic figure, although it is not easy to locate. The Freedonia group has published a report on world fuel demand and some interesting figures from it are cited in a recent issue of INFORM (Anon 2008). World biodiesel demand in 2001, 2006, 2011 and 2016 is given as 1.1, 6.0, 23.6 and 37.5 million tonnes respectively, suggesting annual increases of around 3.5 and 2.8 million tonnes in the five-year periods 2007–11 and 2012–16 respectively. However, part of this demand lies outside the normal range of commodity oils and does not compete with food sources. More recent production figures are given in Table 1.21. Oil and fat supplies increased steadily through the twentieth century. Between 1909 and 1913 supply averaged 13.1 million tonnes, increasing to 20.2 million tonnes in the period

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Production and Trade of Vegetable Oils Table 1.21

EU-27 USA Argentina Brazil Other Total

21

Biodiesel production (million tonnes) from 2006 with estimates for 2010. 2006

2007

2008

2009

2010

Major oil source

4.9 1.1 0 0.1 1.0 7.1

5.9 1.7 0.3 0.4 1.3 9.5

7.5 2.7 0.7 1.0 2.4 14.3

8.4 1.8 1.2 1.4 3.1 15.9

9.5 2.1 1.6 2.0 4.0 19.2

Rapeseed Soybean Soybean Soybean

Source: Gunstone (2010b). Notes: Other countries producing biodiesel include Columbia, Thailand and Malaysia. Animal fats are used to produce 1.0 million tonnes of biodiesel and there is some production of biodiesel from waste fat. Argentina exports most of its biodiesel to EU-27.

Table 1.22 Production of 9 vegetable oils (million tonnes) in the 14-year period 1995/96 to 2008/09. 1995/96 Total (9 oils) Palm Soya Rape Sun Other (5 oils)*

71.2 16.2 20.3 11.1 9.1 14.5

2008/09

Increase (mt)

131.8 42.4 35.7 20.4 11.8 21.5

Increase (%)

60.6 26.2 15.4 9.3 2.7 7.0

85 162 76 84 30 48

Source: USDA, December 2009. Note: * Cottonseed, peanut, olive, coconut and palmkernel oils.

1936–39 and to 29.8 million tonnes in 1956–62 (Hatje 1989; Gunstone 2002; Table 1.2). These figures can be compared with the more recent levels detailed in Table 1.20. Increase in production is larger than the rise in population, so that consumption for all purposes has increased over the last 30 years, as shown in Table 1.20. Annual production between 1960 and 2000 increased by a factor of four and doubled in the 20 years between 1985 and 2005. It remains to be seen whether future increases will be enough to meet the growing food and non-food demand. Traditionally agricultural products have met demands for food, feed and fibre (the three fs). Now another ‘f’ is being added – fuel. As indicated earlier in this chapter, growth in production levels is related mainly to increased production of palm, soy and rapeseed oils.

1.3.6

Predictions for future supply and demand

Production of the nine vegetable oils increased by 60.6 million tonnes (86%) in the 14 years between 1994/95 and 2008/09, with annual increases ranging between 1.4 and 8.9 million tonnes (Table 1.22 and 1.23). Closer examination of the figures shows a marked difference between the first six years, in which the increase was 21.6 million tonnes, and the second six

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Vegetable Oils in Food Technology

Table 1.23 Increases in levels of production of palm, soy, rape and sun oils (million tonnes) in the six-year periods 1994/95 to 2001/02 and 2002/03 to 2008/09.

1995/96 to 2001/02 2002/03 to 2008/09

9 oils

Palm

Soy

Rape

Sun

5 oils

21.6 35.7

9.1 14.8

8.6 5.1

2.0 8.2

–1.6 3.7

3.5 3.9

Source: USDA, December 2009.

Production

45 40

Million tonnes

35 30 Palm

25

Soya

20

Rape

15

Sun

10 5

9 /0 08 20

/0 06 20

04

/0

7

5

3 20

20

02

/0

1 00

/0

9 20

/9 98 19

19

96

/9

7

0

Year Figure 1.4 Production (million tonnes) of palm, soya, rape, and sun oils in the 14 years 1995/96 to 2008/09. Source: USDA, December 2009.

years, with an increase of 35.7 million tonnes perhaps reflecting the increased demand for food and for biodiesel in the last few years. Similar results are shown for selected oils in Table 1.22 and 1.23 and Figure 1.4. The nine vegetable oils increased by 4.3 million tonnes each year.

1.3.7

Sustainability

The concept of sustainability for palm oil and soybean oil arises from concerns by customers in Europe and North America that increased supplies of these two oils for food and fuel should be produced in a sustainable way that does not damage the environment. The first concern was to stop the destruction of tropical rain forests, particularly in South East Asia and Brazil, but the concept has been widened to include other aspects of responsible agriculture, such as the health, housing and education of local people involved in the industry.

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Production and Trade of Vegetable Oils

23

In the case of palm oil, plantation owners strive to meet agreed criteria over a period of time and independent auditors confirm that the required standards have been met for the production of an agreed quantity of palm oil. The owners then receive a certificate for each tonne of oil produced under these conditions and the certificates are sold to concerned buyers at a negotiated price. In one system the sustainable oil is not kept separate from commodity oil and this greatly simplifies the whole operation. In return for his efforts, the supplier has saleable certificates and the purchaser of these can advertise to his customers that a percentage of his purchases represent sustainable palm oil. Marketing of the certificates between trader and purchaser is carried out on the internet with a minimum of effort. Discussions on what is required of a sustainable oil plantation have been going on for some time and it has taken some years for wide-ranging standards to be achieved. The first supplies of sustainable palm oil and their associated certificates were first traded towards the end of 2008, but it is hoped that once started the system will grow rapidly. Appropriate negotiations over soybean oil are also under way.

1.3.8

Genetic modification

The first commercial oilseeds from genetically modified plants appeared in 1996 and have developed since then in terms of the range of crops themselves, the countries in which they are grown and the modified traits present in the GM plants. This has a consequence for the oilseeds, for oils and meals derived from them, and for downstream products such as phospholipids and vitamins. The first genetically modified crops were mainly of benefit to the grower in respect of weed control and pest control. A second generation has modified constituents such as changed fatty acid composition or enhanced vitamin levels. In the oil and fat field the most important GM crops are soybean, rape, cotton and maize (ISAAA website). The area under cultivation by GM crops has increased every year since 1996 and in 2007 reached 114 million hectares. According to ISAAA, ‘the first dozen years of biotech crops have delivered substantial economic and environmental benefits to farmers in both industrial countries and developing countries where millions of farmers have also benefited from social and humanitarian benefits which have contributed to the alleviation of their poverty’. This view is not universally accepted and in Europe in particular there has been a strong reluctance to accept these products and the benefits claimed for them. Biotech crops are now grown in 23 countries, with 8 growing more than 1 million hectares each (USA, Argentina, Brazil, Canada, India, China, Paraguay and South Africa). So much GM soybean is grown in North and in some parts of South America that non-GM soybeans are only available as an identity-preserved (IP) product. There is some evidence that European objection is weakening to GM products in animal feed if not in human food. Reference is made in Chapters 3 and 4 to GM soybeans and rapeseeds with modified fatty acid composition (see also Watkins 2009). These products are considered to be nutritionally or technically superior to the traditional non-modified oils. Considerable effort is being made to develop plants containing long-chain PUFA (especially EPA and DHA) in their seed oils. This has been achieved in the greenhouse/laboratory and is being transferred to the field (Napier 2006). Progress has also been made in developing plants that produce stearidonic acid (18:3 n-3) (Harris et al. 2008) Such material is required to meet the growing demand for nutritionally important acids that are at present only available in fish and fish oils or produced from selected micro-organisms. It will be interesting to see the European reaction to such GM products when they are generally available.

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Genetic modification is also being used to increase yields and harvestable area by increasing resistance to high and low temperatures and for growth in salty and arid soils.

REFERENCES Anon (2008) World demand for biodiesel still rising, INFORM, 19, 324. De Greyt, W. and Kellens, K. (2000) Refining practice, in Edible Oil Processing (eds W. Hamm and R.J. Hamilton), Sheffield Academic Press, Sheffield, pp. 79–128. Dijkstra, A.J. and Segers, J.C. (2007) Production and refining of oils and fats, in The Lipid Handbook, 3rd edn (eds F.D. Gunstone, J.L. Harwood and A.J. Dijkstra), CRC Press, Boca Raton, pp. 143–262. Evans, L.T. (1998) Feeding the Ten Billion: Plants and Population Growth, Cambridge University Press, Cambridge. Fils, J.-M. (2000) The production of oils, in Edible Oil Processing (eds W. Hamm and R. J. Hamilton), Sheffield Academic Press, Sheffield, pp. 47–78. Gunstone, F.D. (2002) Production and trade of vegetable oils, in Vegetable Oils in Food Technology: Composition, Production and Uses (ed. F.D. Gunstone), Blackwell Publishing Ltd., Oxford, pp. 15–16. Gunstone. F.D. (2006) Introduction: Modifying lipids – why and how? In Modifying Lipids for Use in Food (ed. F.D. Gunstone), Woodhead Publishing, Cambridge, pp. 1–8. Gunstone, F.D. (2007a) Update on food and nonfood uses of oils and fats, INFORM, 18, 573–574. Gunstone, F.D. (2007b) Major oils from plant sources, in The Lipid Handbook, 3rd edn (eds F.D. Gunstone, J.L. Harwood and A.J. Dijkstra), CRC Press, Boca Raton, pp. 38–69. Gunstone, F.D. (2008a) Oil and fat supply and demand for the rest of this decade, INFORM, 19, 215–218. Gunstone, F.D. (2008b) Oil and fat forecast. Can we increase supplies? INFORM, 19, 655–656. Gunstone, F.D. (2008c) Phospholipid Technology and Applications, The Oily Press, Bridgwater. Gunstone, F.D. (2009) Non-food uses of vegetable oils, Lipid Technology, 21, 164. Gunstone, F.D. (2010a) Trends in oilseeds and vegetable oils, Lipid Technology, 22, 24. Gunstone, F.D. (2010b) Biodiesel in market report, Lipid Technology, 22, 48. Hamm, W. (2001) Regional differences in edible oil processing procedures. 1. Seed crushing and extraction, oil movements, and degumming. 2. Refining, oil modification, and formulation, Lipid Technology, 13, 81–84, 105–109. Harris, W.S., Lemke, S.L., Hansen, S.N. et al. (2008) Stearidonic acid-enriched soybean oil increased the omega-3 index, an emerging cardiovascular riskmarker, Lipids, 43, 805–811. Hatje, G. (1989) World importance of oil crops and their products, in Oil Crops of the World: Their Breeding and Utilisation (eds G. Robbelen, R.K. Downey and A. Ashri) McGraw-Hill, New York, p. 7. Mielke, T. (ed.) (2002) The Revised Oil World 2020, ISTA Mielke, Hamburg. Mielke, T. (ed.) (2004) Oil World Annual 2004, ISTA Mielke, Hamburg. Mielke, T. (ed.) (2009) Oil World Annual 2009, ISTA Mielke, Hamburg. Mistry, D.E. (2007) Fundamental approach to price forecasting, paper presented at Globoil India, 23 September, available at http://www.seaofindia.com/articles.html, accessed October 2010. Napier, J.A. (2006) The production of n-3 long-chain polyunsaturated fatty acids in transgenic plants, European Journal of Lipid Science and Technology, 108, 965–972. Watkins, C. (2009) Oilseeds of the future. Parts 1–3, INFORM, 20, 276–279, 342–344, 408–410. Wilson, M. (2009) Trans free in America, Oils and Fats International, 25(4), 31–32.

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2

Palm Oil

Siew Wai Lin

2.1

INTRODUCTION

The oil palm (Elaeis guineensis jacquin) originated from South Africa. It was introduced to East Asia as an ornamental plant in the Bogor Botanical Garden in Java, Indonesia in 1848. The descendants spread to different parts of the world as the Deli dura and were utilised for dura × pisera (D × P) seed production. This is the main cultivated oil palm material grown in Malaysia and Indonesia. The Malaysian Palm Oil Board (MPOB), formerly known as PORIM, has the largest collection of oil palm germplasm in the world. The present planting material is mainly dura × pisera (tenera). Commercial plantings in Malaysia have been based on this D × P material as it gives the highest oil yield per bunch (22.5–25.5%). Another species of oil palm, Elaeis oleifera, originates from Central and South America. Its oil is more unsaturated, but the oil-tobunch ratio is extremely low, making it uneconomical to plant on a commercial scale. The oil palm is the most efficient oil-producing plant, with about 3.6–3.7 tonnes/ha/y of palm oil and an additional of 0.42 tonnes/ha of palm kernel oil (Gunstone 2007; Murphy 2007). The yields could be increased further with improved estate and plantation management as well as high-yielding palms. The palm bears fruit that can be harvested in the second to third year of planting in the field, and continues for about 25 to 30 years. Two types of oil are obtained from the oil palm fruit: palm oil from the mesocarp and palm kernel oil from the kernel inside the nut. Fruit bunches are harvested regularly throughout the year, following harvesting standards set by the plantations. Bunches are then transported to the palm oil mills where crude oil and palm kernels are produced by mechanical and physical extraction processes. Oil quality is maintained by careful harvesting of fruits at the optimum stage of ripeness, minimal handling of fruits during transportation, and proper processing conditions during oil extraction.

2.2 2.2.1

COMPOSITION AND PROPERTIES OF PALM OIL AND FRACTIONS Palm oil

Palm oil has a balanced fatty acid composition in which the level of saturated fatty acids is almost equal to that of the unsaturated fatty acids (Table 2.1). Palmitic acid (44–45%) and oleic acid (39–40%) are the major component acids along with linoleic acid (10–11%), Vegetable Oils in Food Technology: Composition, Properties and Uses, Second Edition. Edited by Frank D. Gunstone. © 2011 Blackwell Publishing Ltd. Published 2011 by Blackwell Publishing Ltd.

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Table 2.1

Fatty acid and triacylglycerol composition of palm oil. Malaysian (1981)*

Malaysian (1990)**

Brazilian (1993)§

Mean

Range (215 samples)

Mean

Range (244 samples)

Mean

Range (73 samples)

Fatty acids % by wt 12:0 14:0 16:0 16:1 18:0 18:1 18:2 18:3 20:0

0.2 1.1 44.0 0.1 4.5 39.2 10.1 0.4 0.4

0.1–1.0 0.9–1.5 41.8–46.8 0.1–0.3 4.2–5.1 37.3–40.8 9.1–11.0 0–0.6 0–0.7

0.2 1.1 44.1 0.2 4.4 39.0 10.6 0.3 0.2

0.1–0.4 1.0–1.4 40.9–47.5 0–0.4 3.8–4.8 36.4–41.2 9.2–11.6 0–0.6 0–0.4

0.2 0.8 39.0 0.03 5.0 43.2 11.5 0.4 0.01

Tr–2.6 Tr–1.3 31.9–57.3 Tr–0.4 2.1–6.4 33.8–47.5 6.4–14.8 Tr–0.7 Tr–0.3

Triacylglycerols by carbon number C46 C48 C50 C52 C54 C56

0.8 7.4 42.6 40.5 8.8 ND

0.4–1.2 4.7–10.8 40.0–45.2 38.2–43.8 6.4–11.4 ND

1.2 8.1 39.9 38.8 11.4 0.6

0.7–2.0 4.7–9.7 38.9–41.6 37.1–41.1 10.3–12.1 0.5–0.8

Iodine Value SMP (°C)

53.3 36.0

51.0–55.3 32.3–39.0

52.1 36.7

50.1–54.9 33.0–39.0

NA NA NA NA NA NA 58.0 NA

50.3–62.9 NA

Sources: * Tan et al. (1981); ** Siew et al. (1990); § Tavares and Barberio (1995). Key: ND = not detectable NA = not available SMP = slip melting point

although only a trace amount of linolenic acid is present. The low level of linoleic acid and the virtual absence of linolenic acid make the oil relatively stable to oxidative deterioration. Malaysian palm oil has a narrow compositional range, as indicated from several surveys carried out between 1977 and 1997. The earliest surveys for crude palm oil were recorded by Chin and co-workers (1982) on 215 samples and for both crude and refined oils by Tan and Oh (1981a). King and Sibley (1984) carried out a survey on oils collected from different geographical locations (Malaysia, Ivory Coast, Nigeria, Papua New Guinea, the Solomon Islands and Sumatra). In terms of fatty acid composition, iodine value (IV) and slip melting point (SMP), there are generally no major differences between the oils obtained from the different locations. The iodine values range from 50 to 55. Brazilian palm oil appears to be more unsaturated, containing an average of 43.2% oleic and 11.5% linoleic acids with an IV of 58 (Table 2.1). Iodine values range from 50 to 63 (Tavares and Barberio 1995). Elias and Pantzaris (1997) considered that the oils reported by Travares and Barberio were rather unusual in the wide range for palmitic acid (32–57%) and oleic acid (34–47%) and concluded that the oil in the survey consisted of ‘mixtures of oil of Elaies oleifera with various proportions of stearin’. This would account for the high levels of palmitic acid noted at the maximum end of the range (57.3%) and relates to the fact that the authors had already rejected 26 out of 99 samples as being adulterated.

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Palm Oil

Table 2.2

Fatty acid composition of palm oil from E. guineensis, E. oleifera and their hybrid.

Fatty acids (wt %)

12:0 14:0 16:0 16:1 18:0 18:1 18:2 Others Iodine value

27

E.guineensis (Eg)

0.3 1.2 44.3 – 4.3 39.3 10.0 0.6 55.0

E. oleifera (Eo)

Eg × Eo

Mean

Range

Mean

Range

– 0.2 18.7 1.6 0.9 56.1 21.1 1.0 85.0

– 0.1–0.3 14.4–23.0 NA 0.6–1.8 55.8–64.0 16.2–22.5 NA NA

– 0.5 32.2 0.2 3.2 51.8 10.8 0.9 67.5

– 0.1–0.5 22.4–44.7 NA 1.6–4.9 36.9–60.1 8.8–16.8 NA NA

Sources: Rajanaidu et al. (1985, 2000). Key: NA = not available

It is of interest to mention here that oils from the Elaeis oleifera (South American palm) have oleic acid content as high as 55–64% and linoleic acid content from 16–23% (Rajanaidu et al. 1985). Elaeis oleifera, also known as Elaeis melanococca, can be easily hybridised with Elaeis guineensis, producing oil with characteristics that are between those of the parent oils (Table 2.2). Composition of the oil from the Nigerian population of E. guineensis shows a much larger variation than the commercial oils from planted material. Palmitic acid ranges from 27% to 55%, oleic acid from 28% to 56% and linoleic acid from 6.5% to 18%. These materials provide oil palm breeders with genetic material for developing palms with specifications such as high oleic acid, carotenes or tocopherols. The TAG profile of palm oil has been characterised by carbon number using gas chromatography (Table 2.1). The TAG of palm oil consists of C46 to C56 molecules in a near normal distribution, the major TAGs being C50 and C52. The carbon number represents the number of carbon atoms in the three acyl chains and excludes the glycerol carbon atoms. A more detailed profile of the TAGs is seen in Table 2.3. Palm oil has high contents of disaturated (POP and PPO) and monosaturated (POO and OPO) TAGs. The fatty acids at the sn-2 position of the TAGs are mainly unsaturated (oleic) (Ong and Goh 2002). The polymorphic behaviour of a fat is determined to a large extent by the fatty acids within the TAGs. Fats that are composed of fatty acids predominantly of a single chain length are most likely to be stable in the β form (De Man 1992). Palm oil, containing C16 and C18 acids in most of its glycerol esters, is highly stable in the β′ form. The appreciable amounts of disaturated (POP and PPO) and monosaturated TAGs (POO, OPO and PLO) are apparent as high-melting and low-melting fractions in the differential scanning calorimetry (DSC) thermograms. Three sub-endo peaks observed between 3 °C and 8 °C are linked to the presence of monounsaturates, SUS and diunsaturates, SUU glycerol esters (Braipson-Danthine and Gibon 2007). The two main endo peaks are associated with glycerol esters, which are easily separated into palm olein and palm stearin. Figure 2.1 shows the products obtained from multiple fractionation of palm oil. A wide range of fractions with different properties to suit the requirements of the food industry is available through dry fractionation.

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0.2–0.9 1.3–3.4 0.2–1.0 1.3–2.3 9.0–11.2 6.5–11.0 3.3–6.6 20.5–26.2 27.1–31.0 0.7–7.2 1.0–3.6 4.6–5.9 0.1–1.8 0.1–1.4 3.0–7.6

Range

0.05 2.8 0.6 2.3 11.8 9.9 4.5 26.8 26.6 ND 3.3 4.7 0.07 0.16 5.3

Mean

0.5–0.6 2.3–3.2 0.5–0.7 1.7–2.6 10.9–13.0 9.6–10.2 4.2–5.2 25.1–29.0 23.4–29.4 ND 3.0–3.9 3.9–5.2 0.1–0.3 0.2–0.6 4.7–6.1

Range (n=12)

Palm olein (IV