List of Contributors xiii. List of Abbreviations xv. Introduction xvii. 1 Composition and Properties of Edible Oils 1. Frank D.

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1 List of Contributors xiii List of Abbreviations xv Introduction xvii 1 Composition and Properties of Edible Oils 1 Frank D. Gunstone 1.1 Introduction Components of natural fats Fatty acids and glycerol esters Phospholipids Sterols Tocols and other phenolic compounds Chlorophyll Hydrocarbons Alkanes Squalene Carotenes Polycyclic aromatic hydrocarbons Contaminants and specifications Fatty acid composition Physical properties Polymorphism, crystal structure and melting point Density Viscosity Refractive index Solubility of gases in oils Other physical properties Chemical properties 25

2 1.5.1 Hydrogenation Oxidation Autoxidation Photooxidation Decomposition of hydroperoxides to short-chain compounds Antioxidants Primary antioxidants Secondary antioxidants Stereomutation Double-bond migration and cyclisation Hydrolysis Ester formation Methanolysis Glycerolysis Interesterification Effect of processing on food oil components 33 References 34 2 Bulk Movement of Edible Oils 41 Wolf Hamm 2.1 Oil production and exports Cargo damage Quality of oils shipped Palm oil Soybean oil and other seed oils Shipment of oils intended for production of FAMEs Codex Alimentarius Oil shipments: systems and regulations 49

3 2.5.1 The parcel tanker Parcel tanker categories: IMO classification Trade regulation: the role of the FOSFA and NIOP Shore storage Movement and storage costs Refinery location 53 Acknowledgement 53 References 54 3 Production of Oils 55 Philippe van Doosselaere 3.1 Introduction Seed handling and storage Seed arrival Seed weighing Sampling Seed reception and precleaning Storage Preparation of oilseeds Reason for and purpose of preparation Milling defect Preparation of soybean Cleaning and weighing Cracking Cooking conditioning Flaking Expander Soybean dehulling 68

4 Traditional process Hot dehulling process Preparation and pressing of rapeseed (canola) Preparation Cooking Mechanical pressing Press oil clarification Press cake treatment Preparation and pressing of sunflower seed Full pressing Cold pressing Double pressing Cake treatment Oil from other seeds Cottonseed Corn germ Coconut or copra oil Linseed (flaxseed) Safflower Peanut (groundnut) Rice bran Sesame seed Olive oil production Pressing Centrifugation Olive pomace extraction Palm oil production 91

5 Before reaching the mill Sterilisation Threshing Pressing Crude oil clarification Oil drying Fibre fruit separation Nut conditioning Nut cracking installation Kernel separation Uses of secondary palm fruit products Palm kernel meal Fibres and shell 96 4 Solvent Extraction 97 Timothy G. Kemper 4.1 Introduction Solvent extractor Contact time Particle thickness Extractor temperature Miscella flux rate Number of miscella stages Solvent retention Meal desolventiser toaster Predesolventising trays Countercurrent trays Sparge tray 111

6 4.4 Meal dryer cooler Steam-drying trays Air-drying trays Air-cooling trays Miscella distillation system Solvent recovery system Heat recovery 123 References Edible Oil Refining: Current and Future Technologies 127 Wim De Greyt 5.1 Introduction Next-generation chemical refining with nanoneutralisation Enzymatic degumming: a missing link in the physical refining of soft oils? Bleaching: from single-stage colour removal to multistage adsorptive purification Deodorisation: much more than just a process for the removal of off-flavours Short-path distillation and supercritical processing: refining technologies for the future? 148 References Oil Modification Processes 153 Marc Kellens and Gijs Calliauw 6.1 Introduction Hydrogenation Historical perspective Principle Process parameters Hydrogen pressure 157

7 Temperature Catalyst Process design Future for hydrogenation technology Smarter combinations of the conventional technology Alternative catalysts Advanced process technology Summary Interesterification Historical perspective Principle Process parameters Oil quality Catalyst Oil losses Process design Processed product quality Future for interesterification technology Dry fractionation Historical perspective Principle Process parameters Cooling speed Agitation Process design Crystalliser design Filter design 184

8 Plant design Future for fractionation technology Optimised crystalliser designs High-pressure filtrations Continuous fractional crystallisation Alternative multistage processes for specialty fats production Summary 195 References Enzyme Processing 197 David Cowan 7.1 Introduction Objectives of enzyme processing Enzyme applications before oil refining Enzyme-assisted pressing Enzymatic degumming Enzymatic degumming process (phospholipase A1) Other phospholipases Oil recovery from gums Oil remediation Applications within edible oil modification Industrial-scale enzymatic interesterification Factors influencing enzyme working life Formulating with interesterified oils and fats Enzyme reactions for speciality fats Production of fats high in omega-3 fatty acids Improving processing sustainability through enzyme usage 219

9 References Application of Edible Oils 223 Arjen Bot and Eckhard Fl oter 8.1 Introduction Physical chemistry of triacylglycerides Fat crystal networks Design of functional TAG compositions Application in fat-continuous emulsions (spreads) Application in water-continuous emulsions Mayonnaise and dressings Nondairy (fat) creams and spreads Ice cream Application in other fat-continuous products Baking fats Chocolate Conclusion 245 References Quality and Food Safety Assurance and Control 251 Mar Verhoeff and Gerrit van Duijn 9.1 Introduction Analytical methods for measuring oil and fat composition Quality analyses Free fatty acids Peroxides Phosphorus Moisture and dirt Colour 256

10 9.3.6 Metals Deterioration of Bleachability Index Tocopherols Supply chain contaminants Polycyclic aromatic hydrocarbons Pesticide residues Hydrocarbons of mineral origin Mycotoxins Other contaminants Quality and food safety assurance Crude oil analyses Crude oil risk matrix Process validation contaminant removal Oil processing link tables Food safety control points 264 References Oil Processing Design Basics 267 Gerrit van Duijn and Gerrit den Dekker 10.1 Introduction Refining and modification process routes for most common oil types Process step definitions Degumming or water degumming (degummed) Deep degumming (ddg) Neutralisation (n) One-step bleaching (osb) Two-step bleaching (tsb) Deodorisation (d) 269

11 Deodorisation/stripping (ds) Hydrogenation (h) Interesterification (ie) Dewaxing/winterisation (wi) Dry fractionation (df) Soapstock splitting (ss) Process routes for straight refined oils and fats Process routes pre- and post-hydrogenation Process routes pre- and post-iec Process routes pre- and post-iee Process routes in dry fractionation and dewaxing Oil processing block diagram design Standard oil processing block diagrams Batch and continuous processes Batch processes Continuous processes Refining of straight oils and fats Chemical refining Physical refining Refining combined with hydrogenation Refining combined with interesterification Refining and dewaxing Refining and fractionation Production of trans-free hard fats Effective equipment capacity Example: calculation of effective times for 5- and 7-days-a-week operations 285

12 days a week days a week Tank park design rules Storage capacity Degradation during storage Hydrolysis Oxidation Intermixing with other oils Contamination by chemicals or impurities Tank design rules Tank shape and material of construction Tank heating Tank insulation Avoiding air contact Piping design rules Materials Insulation and heating Layout Design estimates for utilities consumptions and effluent production Introduction Utilities Heating Open steam and vacuum Electrical energy Cooling water Gases Effluent 296

13 Liquid effluent Solid waste Exhaust gases Utility consumption and effluent data per process Storage Refining processes Modification processes Occupational safety by design Introduction General hazards Main occupational hazards of oil refining Neutralisation and soapsplitting Autoignition of spent bleaching earth Deodoriser safety Main occupational hazards of oil modification Hydrogenation safety hazards Safety of IEC Main occupational hazards of oil storage and handling Access to tanks and processing vessels Top access to tank cars 309 References 310 Further Reading 311 Index 313