Fats and oils

SECOND EDITION

FATS and OILS Formulating and Processing for Applications Richard D. O’Brien

CRC PR E S S Boca Raton London New York Washington, D.C. © 2004 by CRC Press LLC

Library of Congress Cataloging-in-Publication Data O’Brien, Richard D. Fats and oils : formulating and processing for applications / by Richard D. O’Brien.— 2nd ed. p. cm. Includes bibliographical references and index. ISBN 0-8493-1599-9 (alk. paper) 1. Oils and fats, Edible. I. Title. TP670.O27 2003 664′.3—dc22

2003055406

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Visit the CRC Press Web site at www.crcpress.com © 2004 by CRC Press LLC No claim to original U.S. Government works International Standard Book Number 0-8493-1599-9 Library of Congress Card Number 2003055406 Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Printed on acid-free paper

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FIRST EDITION PREFACE This book was written as a practical reference for fats and oils processing and formulation for effective food processor, foodservice, and household applications. It is designed to be an information source for personnel and students of fats and oils processing, as well as for personnel of the user industries. A number of books are available that cover various aspects of fats and oils chemistry, technology, and processing; however, the author is not aware of a text devoted to fats and oils processing and formulation from an applications and quality control viewpoint. These are important aspects for the success of a fats and oils processor. Product application influences the design of the finished product. Quality assurance provides consistent, uniform functionality. Applications development and quality management begin when the customer’s requirements are identified and continue through product design, sales, manufacturing, product costing, delivery, and service. This book was designed to delve into the technical aspects that control the functional characteristics of fats and oils products, how these characteristics can be modified to perform as needed, and the processing control necessary to produce these characteristics on a continuing uniform basis at the most economical cost. A thorough understanding of the functions and properties of the various fats and oil products is the basic key to formulating for the desired attributes. Chapters dealing with the raw material or source oils and fats, performance evaluations, formulation attributes, and application were designed to provide the elements of formulation. Control of these processes requires consideration of the problems associated with the properties of the raw materials and each process, as well as customer problems after the sale. Therefore, a quality management chapter was included to help establish when a system is in or out of control, and a troubleshooting chapter was included to identify solutions to problems or at least stimulate the thought process for solving the problem. Fats and oils user industries have always shown a great deal of interest in the development, processing, and quality control of shortening, margarine, and liquid oil products. Tailored fats and oils products for specific applications, processes, nutritional contributions, and other functionalities have been successful due to the cooperative development efforts between fats and oils processors and users. Therefore, this text was compiled with the intent of focusing on applications of fats and oils products for both processors and users. The intent was to help better understand the functionalities, limitations, and potential fats and oils modifications. As stated before, understanding the functions and properties of a shortening, oil, margarine, or other fats-based product is a key element of proper usage and product formulations. Likewise, understanding the requirements of the finished product is necessary to develop fats and oils products that perform more than adequately. Materials for this book have been gathered over the past 35 years from patents, trade journals, scientific journals, personal experience, and exposure to many of the industry’s recognized leaders and many other individuals who have taken a genuine pride in their work and the product produced.

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SECOND EDITION PREFACE The objective of the second edition of this book remains the same as the first: to provide a practical reference for processing and formulation of effective consumer, foodservice, and food processor fats and oils ingredients. Eight major changes or additions were made to improve to the second edition: (1) composition and physical properties for the raw materials have been expanded to provide a more complete information source, (2) information about and characteristics of genetically modified oils have been incorporated, (3) the nutritional aspects of fats and oils are more extensively reviewed, (4) extraction procedures have been incorporated, (5) additional alternative processing procedures are reviewed for several areas, (6) formulation alternatives are explored more extensively, (7) source oil and product use statistics have been updated, and (8) the troubleshooting chapter has been expanded. The additions and modifications are designed not only to revise and update the content of the original but also to expand the content to better identify the available source oils, review alternative processes, explore various formulation techniques, and stimulate the development of new and improved products and processes. The findings of numerous nutritional studies have generated a fair amount of activity since the first edition of this book was prepared. Diet and exercise have been identified as factors that individuals can modify to reduce their risk for chronic diseases such as coronary heart disease. The most important risk factors identified for heart disease are saturated fatty acids, cholesterol, trans-isomers, and obesity. A conscious effort to reduce cholesterol considerably reduced the use of animal fats in the past. Now, recent concerns about trans-isomers acting like saturated fatty acids have encouraged the pursuit of reduced levels of hydrogenated basestocks in many food products. These formulation changes affect source oil selection, processing, and formulation efforts to produce functional fats and oils products. Fats and oils processors must revise their basestock preparation techniques and other processing parameters to produce acceptable product characteristics. These developments indicate that fats and oils processing and formulation require continual attention to adequately serve the needs of their consumers. Understanding the functions and properties of the raw materials along with the effects of the purification and modification processes is essential for the formulation of functional fats and oils products; therefore, the continuing purpose of this book is to serve as an information source for personnel and students of fats and oils processors, as well as for those of the user industries.

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CONTENTS Chapter 1 Raw Materials 1.1 Introduction 1.2 Sources of Fats and Oils 1.3 Vegetable Oil Yields 1.4 Availability of Fats and Oils 1.5 U.S. Utilization of Edible Fats and Oils 1.6 Characterization of Fats and Oils 1.6.1 Nonglyceride Components of Fats and Oils 1.6.1.1 Phospholipids 1.6.1.2 Tocopherols and Tocotrienols 1.6.1.3 Sterols 1.6.1.4 Pigments 1.6.1.5 Pesticides 1.6.1.6 Trace Metals 1.7 Genetically Modified Vegetable Oils 1.8 Soybean Oil 1.8.1 Soybean Oil Composition and Physical Properties 1.8.2 Genetically Modified Soybean Oil 1.9 Cottonseed Oil 1.9.1 Cottonseed Oil Composition and Physical Properties 1.9.2 Genetically Modified Cottonseed Oil 1.10 Peanut Oil 1.10.1 Peanut Oil Composition and Physical Properties 1.10.2 Genetically Modified Peanut Oil 1.11 Corn Oil 1.11.1 Corn Oil Composition and Physical Properties 1.11.2 Genetically Modified Corn Oil 1.12 Sunflower Oil 1.12.1 Sunflower Oil Composition and Physical Properties 1.12.2 NuSun Sunflower Oil 1.12.3 NuSun Composition and Physical Properties 1.13 High-Oleic Sunflower Oil 1.13.1 High-Oleic Sunflower Oil Physical Properties and Composition 1.14 Safflower Oil 1.14.1 Safflower Oil Composition and Physical Properties 1.15 High-Oleic Safflower Oil 1.15.1 High-Oleic Safflower Oil Composition and Physical Characteristics 1.16 Canola Oil 1.16.1 Canola Oil Composition and Physical Properties 1.16.2 Genetically Modified Canola Oil 1.17 Olive Oil 1.17.1 Olive Oil Composition and Physical Properties © 2004 by CRC Press LLC

1.18 Palm Oil 1.18.1 Palm Oil Composition and Physical Properties 1.18.2 Genetically Modified Palm Oil 1.19 Coconut Oil 1.19.1 Coconut Oil Composition and Physical Properties 1.20 Palm Kernel Oil 1.20.1 Palm Kernel Oil Composition and Physical Properties 1.21 Lard 1.21.1 Lard Physical Properties and Composition 1.22 Tallow 1.22.1 Tallow Physical Properties and Composition 1.23 Milk Fat 1.23.1 Milk Fat Physical Properties and Composition References Chapter 2 Fats and Oils Processing 2.1 Introduction 2.2 Fats and Oils Recovery 2.2.1 Oilseed Extraction 2.2.1.1 Expeller or Screw Press Extraction 2.2.1.2 Prepress Solvent Extraction 2.2.1.3 Direct Solvent Extraction 2.2.2 Oil-Bearing Fruit Extraction 2.2.2.1 Olive Oil Extraction 2.2.2.2 Palm Oil Extraction 2.2.3 Animal Fat Recovery 2.2.3.1 Wet Rendering 2.2.3.2 Dry Rendering 2.3 Refining Systems 2.4 Physical Refining 2.4.1 Physical Refining Pretreatment 2.4.2 Water Degumming 2.4.3 Acid Degumming 2.4.4 Dry Degumming 2.4.5 Enzymatic Degumming 2.4.6 Acid Refining 2.5 Chemical Refining 2.5.1 Short-Mix Caustic Soda Refining 2.5.2 Zenith Process 2.5.3 Miscella Refining 2.5.4 Batch Caustic-Soda Refining 2.5.4.1 Dry-Method Batch Refining 2.5.4.2 Wet-Method Batch Refining 2.5.5 Silica Refining 2.5.6 Refining Efficiency 2.5.7 Refining Byproducts © 2004 by CRC Press LLC

2.5.7.1 Soapstock Processing 2.5.7.2 Hydrated Gums Processing 2.6 Prebleaching 2.6.1 Procedure 2.6.1.1 Batch Atmospheric 2.6.1.2 Batch Vacuum 2.6.1.3 Continuous Vacuum 2.6.2 Bleaching Agents 2.6.2.1 Natural Bleaching Earth 2.6.2.2 Activated Bleaching Earth 2.6.2.3 Activated Carbon 2.6.2.4 Silica Adsorbent 2.6.3 Bleaching Earth Dosage 2.6.4 Temperature 2.6.5 Time 2.6.6 Moisture 2.6.7 Filtration 2.6.8 Bleaching Byproduct 2.7 Hydrogenation 2.7.1 Operating Variables 2.7.1.1 Temperature 2.7.1.2 Pressure 2.7.1.3 Agitation 2.7.1.4 Catalyst Level 2.7.1.5 Catalyst Type 2.7.1.6 Catalyst Poisons 2.7.1.7 Catalyst Reuse 2.7.1.8 Source Oils 2.7.2 Hydrogenation Systems 2.7.3 Hydrogenation Control 2.7.4 Hydrogenated Basestock System 2.8 Postbleaching 2.9 Interesterification 2.9.1 Chemical Rearrangement Catalyst 2.9.2 Endpoint Control 2.9.2.1 Melting Point 2.9.2.2 Solids Fat Index 2.9.2.3 Differential Scanning Calorimetry 2.9.2.4 Glyceride Compositional Analysis 2.9.3 Random Chemical Interesterification Process 2.9.4 Directed Chemical Interesterification Process 2.9.5 Enzymatic Interesterification 2.9.6 Interesterified Fats and Oils Applications 2.10 Winterization 2.10.1 Classic Winterization Process 2.10.2 Winterization Principle © 2004 by CRC Press LLC

2.11

2.12

2.13

2.14 2.15

2.16

2.10.2.1 Source Oil Composition 2.10.2.2 Cooling Rate 2.10.2.3 Crystallization Temperature 2.10.2.4 Agitation Rate 2.10.2.5 Crystallization Time 2.10.3 Solvent Winterization 2.10.4 Winterization Process Control Procedures 2.10.5 Winterization Applications Dewaxing 2.11.1 Dewaxing Process Control 2.11.2 Dewaxing Applications Fractionation 2.12.1 Dry Crystal Fractionation 2.12.2 Detergent Fractionation 2.12.3 Solvent Fractionation Esterification or Alcoholysis 2.13.1 Mono- and Diglycerides 2.13.2 Monoglyceride Derivatives 2.13.2.1 Lactylated Monoglycerides 2.13.2.2 Acetylated Monoglycerides 2.13.2.3 Ethoxylated Mono- and Diglycerides 2.13.2.4 Succinylated Monoglycerides 2.13.3 Polyglycerol Esters 2.13.4 Propylene Glycol Monoester Blending Deodorization 2.15.1 Operating Variables 2.15.1.1 Vacuum 2.15.1.2 Temperature 2.15.1.3 Stripping Steam 2.15.1.4 Holding Time 2.15.2 Deodorization Systems 2.15.2.1 Batch 2.15.2.2 Semicontinuous 2.15.2.3 Continuous 2.15.3 Deodorizer Heating Systems 2.15.4 Deodorization Process Control 2.15.5 Deodorizer Distillate Finished Fats and Oils Handling 2.16.1 Protection against Oxidative Deterioration 2.16.1.1 Nitrogen Blanketing 2.16.1.2 Temperature Control 2.16.1.3 Light Control 2.16.1.4 Storage Time

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2.16.1.5 Antioxidant Addition 2.16.1.6 Tocopherols and Tocotrienols 2.16.1.7 Propyl Gallate 2.16.1.8 Butylated Hydroxyanisole 2.16.1.9 Butylated Hydroxytoluene 2.16.1.10 Tertiary Butylhydroquinone (TBHQ) 2.16.1.11 Synergistic Antioxidant Mixtures 2.16.2 Protection against Contamination 2.17 Plasticization 2.17.1 Plasticity of Edible Fats and Oils 2.17.1.1 Product Composition 2.17.1.2 Crystal Size 2.17.1.3 Supercooling 2.17.1.4 Mechanical Working 2.17.1.5 Gas Incorporation 2.17.2 Solidification Apparatus Evolution 2.17.3 Shortening Plasticization Process 2.17.4 Liquid Shortening Crystallization 2.17.5 Margarine Plasticization Process 2.17.5.1 Stick Margarine 2.17.5.2 Soft Tub Margarine 2.17.5.3 Whipped Tub Margarine 2.17.5.4 Liquid Margarine 2.17.5.5 Industrial Margarines 2.17.6 Tempering 2.17.6.1 Quick Tempering 2.18 Flaking 2.18.1 Chill Rolls 2.18.2 Flake Crystallization 2.18.3 Flaking Conditions 2.19 Powdered and Beaded Fats 2.19.1 Spray Cooling 2.19.2 Flake Grinding 2.19.3 Spray Flaking and Grinding 2.20 Salad and Cooking Oils Packaging 2.21 Bulk Oil Shipments 2.21.1 Contamination 2.21.2 Overheating 2.21.3 Air Exposure References Chapter 3 Fats and Oils Analysis 3.1 Introduction 3.2 Nonfatty Impurities

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3.3

3.4

3.5

3.6

3.7

3.2.1 Moisture Analysis 3.2.2 Impurities Analysis 3.2.3 Trace Metals Analysis 3.2.4 Soap Analysis Melting, Solidification, and Consistency 3.3.1 Melting Point Analysis 3.3.2 Solids Liquids Contents Analysis 3.3.2.1 Solids Fat Index 3.3.2.2 Solids Fat Content 3.3.2.3 Differential Scanning Calorimetry Fat Solids Content 3.3.3 Solidification Analysis 3.3.4 Consistency Analysis Composition Analysis 3.4.1 Saponification Value 3.4.2 Iodine Value 3.4.3 Refractive Index 3.4.4 Fatty Acid Composition 3.4.5 Calculated Iodine Value 3.4.6 Glyceride Structure 3.4.7 Emulsifier Analysis 3.4.8 Antioxidant Analysis 3.4.9 Tocopherols Analysis Flavor, Rancidity, and Stability 3.5.1 Flavor Analysis 3.5.1.1 Sensory Evaluations 3.5.1.2 Volatile Flavor Analysis 3.5.2 Rancidity Analysis 3.5.2.1 Peroxide Value 3.5.2.2 Anisidine Value 3.5.2.3 Free Fatty Acid and Acid Value 3.5.2.4 Smoke Point 3.5.3 Stability Analysis 3.5.3.1 Active Oxygen Method Stability 3.5.3.2 Accelerated AOM Stability 3.5.3.3 Oxygen Bomb 3.5.3.4 Oil Stability Index 3.5.3.5 Schaal Oven Test 3.5.3.6 Pastry Flavor Test Color and Appearance 3.6.1 Appearance 3.6.1.1 Product Appearance Ratings Refining and Bleaching 3.7.1 Refining Loss 3.7.2 Neutral Oil and Loss 3.7.3 Bleaching Analysis

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3.8

Performance Testing 3.8.1 Creaming Volume 3.8.2 Pound Cake Test 3.8.3 Icing Volume 3.8.4 White Layer Cakes 3.8.5 Creme Filling Test 3.8.6 Cake Mix Evaluation 3.8.7 Puff Pastry Testing 3.8.8 Restaurant Deep-Fat Frying Evaluation 3.8.9 Ice Cream Bar Coating Evaluation 3.9 Nonstandardized Methods References

Chapter 4 Fats and Oils Formulation 4.1 Introduction 4.2 Source Oils and Fats Characteristics 4.2.1 Short-Chain Fatty Acids 4.2.2 Lauric Fatty Acid 4.2.3 Myristic Fatty Acid 4.2.4 Palmitic Fatty Acid 4.2.5 Stearic Fatty Acid 4.2.6 Long-Chain Saturated Fatty Acids 4.2.7 Oleic Fatty Acid 4.2.8 Essential Fatty Acids 4.2.8.1 Linoleic Fatty Acid 4.2.8.2 Linolenic Fatty Acid 4.2.9 Isomerized Fatty Acids 4.2.10 Erucic Fatty Acid 4.3 Palatability 4.3.1 Oxidative Stability 4.3.1.1 Flavor Reversion 4.3.1.2 Antioxidants 4.3.2 Hydrolysis 4.3.3 Mouth Feel 4.4 Physical Characteristics 4.4.1 Fat Crystal Habit 4.4.2 Fat Plasticity 4.4.3 Solid Liquid Relationships 4.5 Hydrogenated Basestock System 4.6 Solids/Liquids Characteristics 4.6.1 Wide-Plastic-Range Fats and Oils Products 4.6.2 Steep Solids Fat Index Slopes 4.6.3 Liquid Opaque or Pumpable Products 4.7 Reduced and Trans-Free Formulation

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4.8

Emulsification 4.8.1 Mono- and Diglycerides 4.8.2 Propylene Glycol Esters 4.8.3 Sorbitan Esters 4.8.4 Polysorbate Fatty-Acid Esters 4.8.5 Polyglycerol Esters 4.8.6 Lactated Esters 4.8.7 Lecithin 4.8.8 Emulsifier Selection Methods 4.8.8.1 Hydrophilic/Lipophilic Balance System 4.8.8.2 Emulsifier Functionality Traits 4.8.8.3 Emulsifier Selection Procedure 4.9 Product Development 4.9.1 Application Product Development 4.9.2 Analytical Development 4.9.2.1 Solids Fat Index Calculations 4.9.3 Triglyceride Replication 4.10 Source Oils and Fats Interchangeability References Chapter 5 Shortening Types 5.1 Introduction 5.1.1 Historical 5.1.2 Source Oils 5.1.3 Shortening Product Forms 5.2 Plasticized Shortening Applications 5.3 Liquid Shortening Applications 5.4 Flakes, Chips, and Powdered Shortening Applications References Chapter 6 Baking Shortenings 6.1 Introduction 6.2 All-Purpose Shortenings 6.3 Emulsified All-Purpose Shortening 6.4 Retail Cake Mix Shortenings 6.5 Specialty Bakery-Cake Shortenings 6.6 Liquid Cake Shortening 6.7 Icing and Filling Shortenings 6.8 Icing Stabilizers 6.9 Bread Shortening 6.10 Liquid Bread Shortenings 6.11 Sweet Yeast-Raised Dough Shortenings 6.12 Cookie Shortenings 6.13 Cookie Filler Shortenings 6.14 Pie Crust Shortenings 6.15 Biscuit Shortenings © 2004 by CRC Press LLC

6.16 Danish Pastry Roll-In Shortenings 6.17 Puff Paste Roll-In Shortening 6.18 Shortening Chips 6.19 Cracker Shortenings References Chapter 7 Frying Shortenings 7.1 Introduction 7.2 Frying Shortening Additives 7.3 Selection of Frying Shortening 7.3.1 Product Characteristics 7.3.2 Frying Life 7.3.3 Shelf Life 7.4 Shortening Applications for Foodservice Deep-fat Frying 7.4.1 Foodservice All-Purpose Shortening 7.4.2 Animal–Vegetable Blended Frying Shortenings 7.4.3 Heavy-Duty Vegetable Frying Shortenings 7.4.4 Liquid Frying Shortenings 7.4.5 Genetically Modified Vegetable Oils 7.5 Foodservice Pan and Grill Shortenings 7.6 Bakery Frying Shortening Applications 7.6.1 Cake Donut Shortenings 7.6.2 Yeast-Raised Fried Products 7.6.3 Fried Pie Shortenings 7.7 Snack Frying Shortening Applications 7.7.1 Nut-Meats Oil Roasting References Chapter 8 Dairy Analog Shortenings 8.1 Introduction 8.2 Nondairy Creamer Shortenings 8.3 Whipped Topping Shortenings 8.4 Cheese Analog Shortening 8.5 Frozen Dessert or Mellorine 8.6 Sour Cream Analog and Dip Bases 8.7 Fluid Milk Analogs 8.8 Sweetened Condensed Milk Analogs References Chapter 9 Household Shortenings 9.1 Introduction 9.2 Household Shortening Development 9.3 Household Shortening Product Requirements 9.4 Household Shortening Formulation 9.5 Household Shortening Plasticization © 2004 by CRC Press LLC

9.6 Household Shortening Packaging References Chapter 10 Margarine 10.1 Introduction 10.2 Margarine Development 10.3 Margarine Formulation 10.3.1 Milk Products or Protein 10.3.2 Emulsifiers 10.3.3 Flavoring Materials 10.3.4 Preservatives 10.3.5 Vitamins and Colors 10.3.6 Margarine Oils and Fats 10.4 Consumer Margarine Oil Formulations 10.4.1 Trans-Free Consumer Margarine Oil Formulation 10.5 Industrial Margarine Formulations 10.6 Spread Formulations 10.7 Margarine and Spread Preparation 10.7.1 Stick Margarine or Spread 10.7.2 Soft Tub Margarine or Spread 10.7.3 Whipped Tub Margarine or Spread 10.7.4 Liquid Margarine 10.7.5 Industrial Margarines or Spreads References

Chapter 11 Liquid Oils 11.1 Introduction 11.2 Development of Liquid Oils 11.3 Cooking and Salad Oil Sources 11.4 Retail Consumer Oils 11.5 Industrial Salad Oil Applications 11.6 Mayonnaise 11.6.1 Mayonnaise Ingredients 11.6.1.1 Salad Oil 11.6.1.2 Vinegar 11.6.1.3 Eggs 11.6.1.4 Salt 11.6.1.5 Sugar 11.6.1.6 Mustard 11.6.1.7 Pepper 11.6.1.8 Paprika 11.6.2 Mayonnaise Processing 11.7 Spoonable Salad Dressing 11.8 Pourable Salad Dressings 11.8.1 French Dressing © 2004 by CRC Press LLC

11.9 High-Stability Oils 11.9.1 Processed High-Stability Oils 11.9.2 Plant Breeding 11.9.3 High-Stability Oil Applications References Chapter 12 Quality Management 12.1 Introduction 12.2 Operating Standards 12.3 Specifications 12.3.1 Specifications Format 12.3.2 Ingredient Specifications 12.3.2.1 Ingredient Specifications Format 12.3.3 Packaging Specifications 12.3.3.1 Packaging Specifications Format 12.3.4 Product Specifications 12.3.4.1 Product Specifications Format 12.3.5 Customer Instruction Specifications 12.3.5.1 Format of Customer Instruction Specifications 12.3.6 Summary Specifications 12.3.6.1 Summary Specifications Format 12.4 Procedures 12.4.1 Procedures Format 12.4.2 Quality Procedures 12.4.2.1 Complaint Handling Procedure 12.4.2.2 Product Recall Procedure 12.4.2.3 Product Identification Procedures 12.4.2.4 Specification Change Requisition 12.4.2.5 New Product Approval Procedure 12.4.2.6 Weight Control Program 12.4.2.7 Quality Cost System 12.4.2.8 Label Approval Procedure 12.5 Methods 12.5.1 Methods Format 12.6 Process Control 12.6.1 Edible Crude Fats and Oils Process Control 12.6.2 Refining Process Control 12.6.3 Prebleaching Process Control 12.6.4 Hydrogenation Process Control 12.6.5 Postbleach Process Control 12.6.6 Winterization Process Control 12.6.7 Dewaxing Process Control 12.6.8 Blending Process Control 12.6.9 Deodorization Process Control 12.6.10 Bulk Shipment Process Control 12.6.11 Shortening Packaging Process Control © 2004 by CRC Press LLC

12.6.12 12.6.13 12.6.14 12.6.15 References

Liquid Shortening Packaging Process Control Liquid Oils Packaging Process Control Shortening Flake Process Control Standards Margarine and Spread Process Control Standards

Chapter 13 Troubleshooting 13.1 Introduction 13.2 Process Troubleshooting 13.2.1 Vegetable Oil Extraction 13.2.2 Meat Fat Rendering 13.2.3 Crude Oil Storage 13.2.4 Degumming 13.2.5 Caustic Oil Refining — Primary Centrifuge 13.2.6 Oil Refining — Water Wash 13.2.7 Oil Refining — Vacuum Drying 13.2.8 Prebleaching 13.2.9 Hydrogenation 13.2.10 Postbleaching 13.2.11 Winterization 13.2.12 Dewaxing 13.2.13 Esterification 13.2.14 Blending 13.2.15 Deodorization 13.2.16 Antioxidant Addition 13.2.17 Bulk Railroad Car or Truck Loading 13.2.18 Oil Filling and Packaging 13.2.19 Packaged Liquid Oils — Storage and Transportation 13.2.20 Shortening Packaging 13.2.21 Liquid Opaque Shortenings 13.2.22 Shortening Flakes 13.2.23 Packaged Shortening — Storage and Transportation 13.2.24 Quality Control Laboratory 13.2.25 Edible Fats and Oils — Organoleptic Evaluations 13.3 Shortening Applications 13.3.1 Baking Shortening 13.3.2 Frying Shortenings 13.4 Margarine and Spread Products 13.5 Quality Management References

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CHAPTER

1

Raw Materials 1.1 INTRODUCTION Fats and oils are the raw materials for liquid oils, shortenings, margarines, and other specialty or tailored products that are functional ingredients in food products prepared by food processors and restaurants and in the home. Humans have used fats and oils for food and a variety of other applications since prehistoric times, as they were easily isolated from their source. For example, fatty tissues from animals liberate free-floating fats on being boiled, whereas oil can be pressed from olives and oilseeds. Fats and oils found utility because of their unique properties. These ingredients were found to add flavor, lubricity, texture, and satiety to foods. They have also been found to have a major role in human nutrition. Fats and oils are the highest energy source of the three basic foods (carbohydrates, proteins, and fats), and many contain fatty acids essential for health that are not manufactured by the human body. Fats and oils occur naturally in a wide range of sources, with each source providing a separate and distinctive material. Hundreds of seeds and fruits bear oil, all animals produce fat, and marine sources also provide oils; however, only a few of these sources are of economic importance. All edible fats and oils are waterinsoluble substances that consist predominantly of glyceryl esters of fatty acids, or triglycerides, with some nonglyceridic materials present in small or trace quantities. The terms fats and oils are used interchangeably, and the choice of terms is usually based on the physical state of the material at ambient temperature and tradition. Generally, fats appear solid at ambient temperatures and oils appear liquid. In the final analysis, it is the chemical composition that defines the characteristics of the individual fat or oil, which in turn determines the suitability of this ingredient in various processes and applications. 1.2 SOURCES OF FATS AND OILS Humans have survived as hunters and gatherers for a majority of their known existence on Earth. It was only during the last 10,000 years that they learned to

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domesticate plants and animals. During this period, the evolution of cultivated plants has been shaped to the needs of modern humans. Today’s agricultural crops are mankind’s creation. Humans cannot survive without them, nor can the crops that have been developed survive without their care. The combined largest source of vegetable oils is the seeds of annual plants grown in relatively temperate climates. Most of these annual plants not only are cultivated as a source of oil but are also utilized as protein-rich foods. A second source of vegetable oil is oil-bearing trees. Olive, coconut, and palm oils are extracted from the fruit pulp rather than the seed of the fruit. Palm also has seeds, which provide palm kernel oil. All of the oil-bearing tree fruits require a relatively warm climate (i.e., tropical for coconut and palm and a warm climate for olive trees). Most of the oil-bearing tree fruits and kernels provide the highest oil yields. Oil seeds are obtained from annual plants that must be replanted each year, whereas fruit oils are harvested from trees with long life spans. Olive trees are the most hardy and can survive to be several hundred years old. Coconut trees start to bear fruit after 5 to 6 years, and their life expectancy is as long as 60 years. Palm trees start to bear fruit after 4 to 5 years and continue to do so for another 20 years. Edible meat fats are supplied almost entirely by three kinds of domesticated animals: lard from pigs, tallow from cattle and sheep, and milk fat or butter from cows. These animals are raised in the greatest quantities where they thrive the best — in temperate climates. Animal husbandry has evolved to the stage that these domestic animals require not only a temperate climate but also intensive agriculture to provide a plentiful supply of foodstuffs to produce the desired quality and quantity.

1.3 VEGETABLE OIL YIELDS Fats and oils are renewable resources. The achievements of agriculture and plant cultivation have made it possible to exceed the demand resulting from world population growth. The major vegetable oil seeds and fruits utilized for edible purposes are listed on Table 1.1 with their typical oil contents, yield per acre of land, and major producing areas.1 Palm is unparalleled in oil yield. The palm oil yield of palm trees is 2670 to 4450 pounds per acre, and an additional yield of 267 to 445 pounds per acre of palm kernel oil is obtained from the same fruit bunch. Palm trees yield almost 10 times the soybean oil yield per acre. Most oil seeds are annual crops, and the harvest is seasonal; however, palm oil is a perennial crop, with two crops produced per year. Coconut, also with a high oil content and yield, requires 9 to 12 months to mature, but fruit is available each month of the year. Olives mature annually and are the most delicate fruit; extraction must be performed as soon as possible to obtain a quality oil. Olives have the lowest yield per acre of all the oils evaluated, even though their oil content is about equivalent to cottonseed and much higher than corn germ. The production of 1 quart of olive oil requires 1300 to 2000 olives. Three of the four tree oils have the highest oil contents, but soybean, an annual oil seed crop with a low oil content, still provides the largest vegetable oil production in the world. Corn, with the lowest oil content, is grown in large enough quantities to be the third most utilized vegetable oil in the United States. Canola, © 2004 by CRC Press LLC

Table 1.1

Vegetable Oils: Oil Content, Yield, and Producing Areas Oil Content (%)

Oil Yield (Pounds/Acre)

Oilseeds: Canola

40–45

525–590

Corn

3.1–5.7

215–390

Cottonseed

18–20

185–210

Peanut

45–50

1120–1245

Safflower Soybean

30–35 18–20

545–635 400–450

Sunflower

35–45

460–590

Tree fruits and kernels: Coconut 65–68

650–870

Oil

Olive

15–35

90–260

Palm

45–50

2670–4450

Palm kernel

44–53

267–445

Producing Areas Canada, China, India, France, Austria, United Kingdom, Germany, Poland, Denmark, Czechoslovakia, United States United States, Mexico, Canada, Japan, China, Brazil, South Africa, Argentina, Russia, Commonwealth of Independent States (CIS), Belgium, France, Italy, Germany, Spain, United Kingdom China, Russia, United States, India, Pakistan, CIS, Brazil, Egypt, Turkey, Australia China, India, Nigeria, United States, Senegal, South Africa, Argentina China, United States, Spain, Portugal United States, Brazil, Argentina, China, India, Paraguay, Bolivia Russia, Argentina, CIS, Austria, France, Italy, Germany, Spain, United States, United Kingdom Philippines, Indonesia, India, Mexico, Sri Lanka, Thailand, Malaysia, Vietnam, Mozambique, New Guinea, Ivory Coast Spain, Italy, Greece, Tunisia, Turkey, Morocco, Portugal, Syria, Algiers, Yugoslavia, Cyprus, Egypt, Israel, Libya, Jordan, Lebanon, Argentina, Chile, Mexico, Peru, United States, Australia Malaysia, Indonesia, China, Philippines, Pakistan, Mexico, Bangladesh, Colombia, Ecuador, Nigeria, Ivory Coast Malaysia, Indonesia, China, Philippines, Pakistan, Mexico, Bangladesh, Colombia, Ecuador, Nigeria, Ivory Coast

an annual oil seed crop developed and grown for its oil composition, has moved from a virtual unknown to second in oil utilization only to soybean oil. Canola seed has the second highest oil content and oil yield per acre of all the annual plants presented in Table 1.1; it is surpassed only by peanut or groundnut oil content and yield.

1.4 AVAILABILITY OF FATS AND OILS An important contributor to the availability of fats and oils is the fact that most fats and oils production is controlled by factors other than the demand. Corn and cottonseed oils are clearly byproducts, whereas soybeans are specifically crushed to meet the demands for meal. Sunflower, canola, and peanut plantings are subsidized and controlled by the governments of the major producing countries. Palm kernel © 2004 by CRC Press LLC

oil production is dependent upon palm oil requirements, as it is grown in the same fruit bunch. Olive, coconut, and palm oils are all produced from the fruit of trees that have long productive life spans; therefore, their production cannot be adjusted to demand changes from year to year. Animal fats are dependent upon meat consumption, and butter output is subject to milk production. Thus, the availability of fats and oils is not geared to demand. Weather is another factor that affects both availability and demand for fats and oils. For example, a hurricane in Malaysia can decrease the oil available on the world market; alternatively, favorable weather in the United States, which produces a soybean crop with maximum yields, will increase the available oil for the world market. Other factors that affect world demand are the Russian sunflower crop, African peanut crop, South American soybeans and cottonseed oil yields, and so forth. This is a one-world market in which variable inputs affect availability and demand, which in turn affect the price structure.

1.5 U.S. UTILIZATION OF EDIBLE FATS AND OILS Climate and availability certainly influenced the eating habits of our ancestors. Inhabitants of central and northern Europe obtained their edible fats from animals, whereas people in southern Europe, Asia, and Africa acquired their edible oils from vegetable sources. The food products developed in these different regions used the available fats and oils products. Consequently, the cuisine of central and northern European countries developed around the use of solid fats such as butter, lard, and tallow for breads, pastries, and other baked and fried products. Similarly, the diets of inhabitants from warmer climates were developed around the use of liquid oils for their food products, which include many sauces and dressings.2 These trends appear to continue to be the preference of their descendants. Immigrants to the United States brought their food preferences with them and introduced them to others from different regions of the world. Fats and oils technology has further increased the varied and rich American diet by improvement of existing products and development of new food products. The North American eating habits that resulted have made the United States a consumer of almost every available fat and oil but at a different rank order than for world production. Table 1.2 compares the U.S. and world vegetable oil consumption.3 Soybean oil does not enjoy the dominant position in the world market that it has in the U.S. market. Overall, it was the leading vegetable oil for the year 2000, but when the U.S. consumption is taken away palm oil becomes the major source of oil, followed by soybean, rapeseed, and sunflower oil. The American consumer is offered these fats and oils in the form of cooking or salad oils; butter, margarine, or spreads; and shortenings or as an ingredient in a prepared food product. The sources of the major fats and oils used in the United States are listed in Table 1.3, which reviews the annual usage of both animal fats and vegetable oils over the past 5 decades.3–5 These data indicate some distinct trends over the past 50 years: (1) continuing increase in individual consumption, (2) a move away from animal fats to vegetable oils, (3) replacement of previously established © 2004 by CRC Press LLC

Table 1.2 2001/2002 World Vegetable Oil Production (million pounds) Rank Order 1 2 3 4 5 6 7 8 9 10 a

With U.S. Usage Soybean Palm Canola Sunflower Peanut Cottonseed Coconut Palm Kernel Olive Corna Total

63,184 54,736 26,840 16,654 9460 8404 7172 6842 5566 2459 201,317

U.S. Usage (%)

Without U.S. Usage Palm Soybean Canola Sunflower Peanut Cottonseed Coconut Palm kernel Olive Corn Total

54,265 46,226 25,347 16,279 9210 7637 6072 6487 5111 1130 177,764

0.86 26.84 5.56 2.35 2.64 9.13 15.34 5.19 8.17 45.96 11.70

U.S. production only.

Table 1.3 Fat or Oil

U.S. Edible Fats and Oils Disappearance and Per Capita Consumption 1950

1960

Canola — — Coconut 129 172 Corn 223 310 Cottonseed 1445 1225 Olive 79 51 Palm — 1 Palm kernel 26 53 Peanut 103 62 Safflower — — Soybean 1446 3011 Sunflower — — Lard 2050 1889 Tallow 156 328 Butter 1327 1113 Total 6984 8215 Per capita consumption (pounds) Vegetable oils 24.0 26.7 Animal fats 21.9 18.5 Total 45.9 45.3

Year (Millions of Pounds) 1970 1980 1990 — 788 445 891 67 182 94 193 100 6253 — 1645 518 1075 12,251 39.0 14.1 53.0

— 1032 673 523 58 299 NR 112 — 9114 64 1023 995 1017 14,910 45.0 12.2 57.2

577 897 1149 851 211 256 362 197 58 12,164 200 825 955 1095 19,797 52.8 9.4 62.2

2000 1744 968 1711 674 455 375 243 244 102 16,210 357 962 1498 1022 26,565 63.1 11.5 74.6

Note: NR = not reported.

fats and oils with different source oils, (4) introduction of new vegetable oils, (5) the rise and fall of some individual source oils, (6) source oil changes that reflect the results of medical studies, (7) introduction of genetically modified oil seed varieties, and more. Disappearance of fats and oils in the United States has increased to almost four times the levels recorded 50 years ago. This increased usage is due to increases in population, personal consumption, food waste, and changes in the food preparation © 2004 by CRC Press LLC

methods. The per capita use of visible fats and oils increased by almost 29 pounds during this period, confirming an increase in personal usage either from consumption or waste. The changes in the food fats utilized reflect the changing eating habits of Americans in relation to time, place, and frequency of eating. During the periods of high increases, the popularity of convenience and snack foods rose sharply, accompanied by rapid growth in the fast food industry, which relies heavily upon deep-fat frying. Fats and oils consumption has been categorized into visible and invisible sources. Visible fats and oils are those isolated from animal tissues, oilseeds, or oil fruits and used for food preparation as shortening, margarine, or liquid oil or for specialty uses. Invisible fats and oils are consumed as part of meats, poultry, eggs, dairy products, fish, fruits, or vegetables and account for approximately 60% of an individual’s fat consumption. The values for pounds per person reported in Table 1.3 are those from visible sources only. A shift from animal fats to vegetable oils began before 1950. Animal fats dominated the U.S. market until animal-fat supply shortages and new process developments helped cottonseed oil gain popularity. In 1950, animal fats were only slightly behind in market share, but 20 years later, in 1970, edible vegetable oils accounted for three fourths of the total and animal fats for only one fourth. This trend has continued, with vegetable oil commanding almost 85% of the U.S. edible oil market in 2000. On a per capita basis, edible vegetable oil consumption increased during the second half of the 20th century from 24 to 63.1 pounds; meanwhile, animal fats usage fell from 21.9 to 11.5 pounds. During this period, cottonseed oil lost its dominant vegetable oil position to soybean oil, due to cottonseed supply shortages and economics. Vegetable oils became dominant mainly because of competitive pricing (first for cottonseed oil and then for soybean oil), increased hydrogenation capacity, consumer preference shifts from butter to margarine, and nutritional concerns regarding cholesterol and saturated fats. Nutritional issues helped other vegetable oils obtain a share of the U.S. market. Canola, corn, olive, sunflower, and safflower oils have all been marketed as oils with more attractive nutritional values, such as lower levels of saturated fat and higher levels of polyunsaturated fat. 1.6 CHARACTERIZATION OF FATS AND OILS The chemical and physical properties of fats and oils are largely determined by the fatty acids that they contain and their position within the triacylglycerol molecule. Chemically, all fats and oils are esters of glycerin and fatty acids; nevertheless, the physical properties of natural fats and oils vary widely because: (1) the proportions of fatty acids vary over wide ranges, and (2) the triacylglycerol structures vary for each individual oil and fat. Fats and oils are commonly referred to as triglycerides because the glycerin molecule has three hydroxyl groups where a fatty acid can be attached. All triglycerides have the same glycerin unit, so it is the fatty acids that contribute the different properties. The fatty acid components are distinguished in three ways: (1) chain length, (2) number and position of the double bonds, and

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(3) position of the fatty acids within the glyceride molecule. Variations in these characteristics are responsible for the chemical and physical differences experienced with edible fats and oils. The structure of a fatty acid is commonly denoted by a systematic name after the nomenclature of its parent hydrocarbon, by its common name, or by a convenient shorthand designation showing the number of carbon atoms and the number of double bonds. The fatty-acid carbon-chain lengths vary between 4 and 24 carbon atoms with up to three double bonds. The most prevalent saturated fatty acids are lauric (C-12:0), myristic (C-14:0), palmitic (C-16:0), stearic (C-18:0), arachidic (C-20:0), behenic (C-22:0), and lignoceric (C-24:0). The most important monounsaturated fatty acids are oleic (C-18:1) and erucic (C-22:1). The essential polyunsaturated fatty acids are linoleic (C-18:2) and linolenic (C-18:3). The triglyceride structure of an edible fat or oil is affected by the fatty acids present and the point of attachment of each fatty acid to the glycerin. Triglycerides with three identical fatty acids are called monoacid triglycerides. Triglycerides containing more than one type of fatty acid are called mixed triglycerides. A mixed triglyceride containing three different fatty acids has three regioisomeric forms and six stereoisomeric forms, depending on which fatty acid is in the beta or middle position (sn-2) of the glycerol portion of the molecule and which fatty acids are in the alpha or outer positions (sn-1 and sn-3). The distribution of the fatty acids is considered to be nonrandom when the saturated fatty acids are positioned predominantly in the sn-1 or sn-3 positions and the unsaturated fatty acids are positioned predominantly in the sn-2 position.6 The fatty acid compositions of natural fats and oils vary significantly depending not only on the plant or animal species but also within the same species. Among the factors that affect the vegetable oil fatty acid compositions are climate conditions, soil type, growing season, plant maturity, plant health, microbiological conditions, seed location within the flower, and genetic variation of the plant. Animal fat and oil composition varies according to the animal species, diet, health, fat location on the carcass, and maturity.7 1.6.1

Nonglyceride Components of Fats and Oils

The primary constituents in crude fats and oils are the triglycerides, but they also contain varying amounts of minor components, many of which significantly affect their chemical and physical properties. Exclusive of free fatty acids, crude vegetable oils commonly contain 2% or more nonglyceride substances, and animal fats contain much smaller quantities. These minor components, also referred to as the unsaponifiable fraction, consist of phospholipids, tocopherols, sterols, resins, carbohydrates, pesticides, proteins, trace metals, and pigments such as gossypol, carotene, and chlorophyll. Some but not all of the nonglyceride materials are undesirable; therefore, the objective in all edible oil processing is to remove the objectionable impurities with the least possible damage to the desirable constituents.

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1.6.1.1 Phospholipids These compounds are better known to oil processors as phosphatides and are frequently referred to, together with small quantities of carbohydrates and resins, as gums, which have adverse effects on product quality and refined oil yield. Phosphatides are emulsifiers and hinder the separation of oil and water phases in the chemical refining process, interfere with effective bleaching, are catalyst poisons, shorten shelf life, and foul equipment surfaces. Phosphatides consist of polyhydric alcohols esterified with fatty acids and phosphoric acid, which is combined with a nitrogen-containing compound. The phosphatides are divided into two categories: hydratable and nonhydratable, depending upon the effect that water has on them. The hydratable phosphatides (phosphatidylcholine and phosphatidylinositol) can be separated from the oil phase with water. The nonhydratable phosphatides (phosphatidic acid and lysophosphatidic acid) and the calcium and magnesium salts of these acids remain in the oil after water degumming. A typical water degumming process will remove the hydratable phosphatides to a level of 200 ppm phosphorus for soybean and canola oils. Pretreatment of good-quality crude oils with phosphoric or citric acid before refining is successful in removing both nonhydratable and hydratable phosphatides to a phosphorus level of approximately 20 to 30 ppm. Two common phosphatides occurring in vegetable oils are the lecithins and cephalins, which may be considered triglycerides that have one fatty acid replaced with phosphoric acid. The gums separated with a water degumming process can be dried for lecithin processing; however, the gums isolated with an acid degumming processes are not suitable for standard lecithin because their phosphatide composition differs and they contain the degumming acid. As indicated in Table 1.4, all the seed oils contain significant quantities of the phosphatides.8–10

Table 1.4 Fats and Oils Nonglyceride Components Fat or Oil

Phosphatides (%)

Sterols (ppm)

Cholesterol (ppm)

Tocopherols (ppm)

Soybean Canola Corn Cottonseed Sunflower Safflower Peanut Olive Palm Tallow Lard Coconut Palm kernel

2.2 ± 1.0 2.0 ± 1.0 1.25 ± 0.25 0.8 ± 0.1 0.7 ± 0.2 0.5 ± 0.1 0.35 ± 0.05