Ice Cream
lee Cream SIXTH EDITION Robert T. Marshall UniverJity of Missouri-Columbia Co/umbia, MisJouri H. Douglas Goff Univmity vi Guelph Wellingum. Onlario, CanaM and Richard W. Hartel Univer5it)" vi WiJ-CQlI.!in Madison. Wisconsin Springer Science+Business Media, LLC
Library or Congre8' Calalogillg-in-PublicHlion DalH Marshall. Roben T.. 1932- lee erearnlroben T. Marshall. H. Douglas GoR", and Hichard W. Hancl.-6th cd. p. cm. Indudes bibliographical referenees. ISBN 978-1 -4613 4948-8 ISBN 978-1 4615 0163 3 (cßook) DOI 10.1007/978-1-4615-0163-3 I. lee eream, ices, eie. I. GoR", H. Douglas, 1960-11. Hanel. Richard W., 1951-111. Tille. TX795.M2'J52003 64I.S'62-de21 2003044747 ISBN 978-1-461 3-4948-8 0 2003 Sjlringer Scicnce+Busincss Media Ne,," York Originlilly pulliished by Kluwcr Acadcmic!Plcnum Publishcrs. Ncw Yor~ in 2003 Softcover reprint of the hardcover 6tll edition 2003 hll[':1!w...,, kap.eom 10 9 S 7 6 5 4 3 2 I A c.i.p. rerord for this book is a.ailable from thc Library or Congress All rights reser. cd No pan of this book may be reproduccd. stored in a retrieval system. (Ir trnnsmiucd in an)" foml (Ir by any means, electronic, mechanical. jjhotocop)'ing, mierofilming. recording, or O1herwise. "'ithout wrilten pennission from the Publisher, with the cxccjjtion of any material sul'l'l icd spe<:ilically for the purfx'sc of being entered and execu t ~-d on 8 COßljJuter system. fot exdusi"c use by the purchaser of the "ork Pennissions for books publishcd in Europe: permmwns@.. kap.nl Pennissions for hooks publishcd in the Unitcd States or America: permilsions@.. kofl.rom
Preface Ice cream is a complex food colloid embodied in a product the consumer associates with pure enjoyment. It is paradoxical that what can seem so simple is indeed so complex. Ice cream consists of at least three major discrete phases, viz., ice crystals, air bubbles and fat globules, the latter partially coalesced, and minor discrete phases of casein micelles and perhaps even lactose crystals, all embedded in a freeze-concentrated unfrozen matrix of dissolved andior suspended sugars, whey proteins, salts and polysaccharides. The science is obvious to the professional, but to those consumers who see ice cream as pure pleasure, what is ice cream science? This 6th edition of Ice Cream continues a series begun in 1966 by Professor W. S. Arbuckle of the University of Maryland. Arbuckle had joined Professor J. H. Frandsen in co-authoring Ice Cream and Related Frozen Desserts in 1961. Frandsen was the senior author oftwo other ice cream books in 1915 and 1950. So, the lineage of this book can be traced back to the infancy of the ice cream industry. The senior author of the 5th edition, R. T. Marshall, is joined in this new edition by two scientists whose expertise in physical chemistry, H. D. Goff, and engineering, R. W. Hartel, add significant breadth and depth based on their research, teaching and outreach to the frozen desserts industry. Classic ice cream textbooks from 40 to 50 years ago describe ingredients, formulations, manufacturing processes, equipment and product quality defects that are not unlike those of today. Despite the immense number of new products that are available in the market today, one might argue that there have been very few paradigm shifts in ice cream science and technology. However, is this a fair argument? Certainly there have been tremendous advances in understanding of the chemistry and physics of ice cream. There have also been more than just subtle shifts in ingredients, with more use of non-dairy fats, milk protein ingredients, starch hydrolysate sweeteners and other alternatives to sucrose, and stabilizing and emulsifying agents. Processing advances have included sophisticated, automated continuous freezers with precise control of overrun and dosing of particulate ingredients, sophisticated processing technology for manufacture of hand-held impulse products, rapid hardening equipment, and automated storage and retrieval equipment. We have added the international dimension to the book in important places. Each of us has participated in one or both of the International Symposia on v
vi PREFACE Ice Cream sponsored by the International Dairy Federation in 1997 and 2003. It is our hope that because of our efforts to educate through our writings and presentations we will have increased the likelihood that consumers of all nations will be given the opportunity to purchase the delicious products of our industry. Although large, national and international firms produce much of the total volume of frozen desserts, the industry is home also for many small manufacturers and dealers. The wide variety of ingredients and packages available allows for easy differentiation of one firm's products from those of other producers. This makes possible entry into the market by individual entrepreneurs. Thus, it becomes relevant for a host of people to study the science and technology of ice cream production. We dedicate this edition to our students who have contributed thousands of hours to discovery in the several disciplines we collectively represent. Furthermore, we recognize our institutional colleagues and our industry cooperators who have shared their facilities, expertise and funding to facilitate our research. Sincere appreciation is extended to our families without whose support and encouragement we would not have accomplished our goals. We are confident that these contributions have enhanced this edition to the great benefit of our readers. R. T. Marshall H.D.Goff R. W. Hartel
Contents 1 The Ice Cream Industry Introduction Characteristics of the Industry Historical Background Production and Consumption Our Thoughts 1 1 1 2 7 9 9 2 Composition and Properties 11 Classifications of Ice Cream and Related Products 12 Descriptions of Commercial Frozen Desserts 14 Flavor Categories for Ice Cream 17 Complexities of Composition 18 Energy Value and Nutrients 20 Characteristics of a Satisfactory Composition 26 The Roles of the Constituents 27 Importance of Flavor 37 The Balanced Mix 38 Fat Destabilization and Foam Formation in Frozen Dairy Desserts 38 Physical Properties of Mixes 44 50 3 Ice Cream Ingredients Optional Ingredients Composition of Milk 55 55 55 vii
viii 4 Milk Products Used in Ice Cream Non-Dairy Fats Fat Replacers Sweeteners Salt Stabilizers Ice Cream Improvers Ice Structuring Proteins Emulsifiers Flavoring and Coloring Materials Flavors for Frozen Desserts Vanilla Chocolate and Cocoa Fruits in Frozen Desserts Procedures and Recipes Nuts Spices and Salt Flavoring Lowfat, Nonfat and Special Frozen Desserts Color in Frozen Desserts Comments 5 Calculation of Ice Cream Mixes The Importance of Calculations Mathematical Processes Most Frequently Used Standardizing Milk and Cream Mix Formulation Calculations Use of Computers to Solve Mix Formulation Calculations Freezing Point Depression Calculations Overrun Calculations 6 Mix Processing Preparation of the Mix Pasteurization of the Mix Homogenization ICE CREAM 60 69 70 73 79 80 84 85 85 86 89 91 92 96 101 107 112 113 114 115 116 116 119 119 119 120 122 138 139 143 147 149 149 157 161
CONTENTS Aging Mixes Packaging Mixes for Sale Flavoring Mixes ix 167 167 168 168 7 The Freezing Process 171 Prefreezing Tests 171 General Freezing Operations 171 Changes that Take Place During the Dynamic Freezing Process 173 Refrigeration Needed to Freeze Ice Cream 183 Types of Freezers 186 The Continuous Freezer 187 The Batch Freezer 202 205 8 Refrigeration 207 Types of Refrigerants 208 Mechanical Refrigeration 213 Terms Used in Refrigeration 222 9 Packaging, Labeling, Hardening and Shipping Considering the Package Labeling The Packaging Operation The Hardening Process Handling, Storing and Shipping Quality is the Goal 10 Soft-Frozen Dairy Desserts Soft-Serve Products Soft-Serve Mix Composition Freezers for Soft-Serve and Shakes Cleaning and Sanitizing Soft-Serve Freezers The Heat Treatment Freezer Soft-Serve Blended Products Reference 225 225 227 232 240 246 251 252 253 253 253 256 260 261 262 263
x ICE CREAM 11 Sherbets, Sorbets and Ices 265 The Composition of Sherbets, Sorbets and Ices 266 Preparation ofices 269 Preparation of Sherbets 269 Freezing Ices and Sherbets 271 Defects 272 Reference 273 12 Fancy M.olded Ice Creams, Novelties and Specials 275 Production Systems 276 Specialty Equipment 276 Ice and Fudge Stick Items 285 Chocolate Coatings 285 Other Special Products 289 Reference 294 13 Analyzing Frozen Desserts Introduction Chemical and Compositional Properties Physical Properties Microbiological Properties Sampling for Microbiological Tests Sensory Properties Defects, Scoring, and Grading Flavor Defects Body and Texture Defects Color Package Melting Quality Methods of Determining Sensory Quality Ice Cream Clinics 295 295 295 296 301 303 304 304 305 309 315 315 316 317 323 324 14 Cleaning, Sanitizing, M.icrobiological Quality and Safety 327 Planning for Product Safety 327 Cleaning Equipment 330 Functions of Detergents in the Dairy 330
CONTENTS 15 Major Detergent Components and Their Functions Principles of Cleaning Sanitization of Equipment Controlling and Monitoring Plant Sanitation Sanitary Environment Hygienic Personnel Tests of the Finished Product Summary Formulas and Recipes Plain Ice Cream Candy or Confection Ice Cream Chocolate Ice Cream Fruit Ice Creams Frozen Yogurt Nut Ice Creams Puddings Parfait Mousse Frappe Sorbets Punch Granite Sherbets Souffle Lacto Fruit Salad Fancy Molded Ice Cream Spumoni Frosted Malted Specials Low- or Reduced-Lactose Ice Cream Ice Creams of Lowered Fat Content Index xi 331 332 337 339 339 340 340 342 342 343 343 344 345 345 346 347 348 349 349 349 349 349 351 351 351 352 353 355 357