FUNDAMENTALS OF DAIRY CHEMISTRY THIRD EDITION FUNDAMENTALS OF tlfDAIRY CHEMISTRY THIRD EDITION Editor Noble P. Wong Agricultural Research Service U.S. Department of Agriculture Associate Editors Robert Jenness formerly Department of Biochemistry University of Minnesota Mark Keeney Department of Chemistry and Biochemistry University of Maryland Elmer H. Marth Department of Food Science University of Wisconsin ~ Van Nostrand Reinhold Company ~ ___________________ NewYork AnAVI Book (AVI is an imprint of Van Nostrand Reinhold Company Inc.) Copyright © 1988 by Van Nostrand Reinhold Company Inc. Softcover reprint of the hardcover 3nd edition 1988 Library of Congress Catalog Card Number 87-21586 All rights reserved. Certain portions of this work © 1974, 1965 by Van Nos trand Reinhold Company Inc. No part of this work covered by the copyright hereon may be reproduced or used in any form or by any means-graphic, electronic, or mechanical, including photocopying, recording, taping, or infor mation storage and retrieval systems-without permission of the publisher. Van Nostrand Reinhold Company Inc. 115 Fifth Avenue New York, New York 10003 Van Nostrand Reinhold Company Limited Molly Millars Lane Wo kingham, Berkshire, RG 11 2PY, England Van Nostrand Reinhold 480 La Trobe Street Melbourne, Victoria 3000, Australia Macmillan of Canada Division of Canada Publishing Corporation 164 Commander Boulevard Agincourt, Ontario MIS 3C7, Canada 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 Library of Congress Cataloging-in-Publication Data Fundamentals· of dairy chemistry. "An AVI book." Includes bibliographies and index. 1. Milk-Composition. 2. Dairy products Composition. I. Wong, Noble P. SF251.F78 1988 637 87-21586 ISBN-13: 978-0-442-20489-1 e-ISBN-13: 978-1-4615-7050-9 DOl: 10.1007/978-1-4615-7050-9 To BYRON H. WEBB for his outstanding dedicated service to the dairy in dustry that spans half a century and whose persist ence and guidance has led to another edition of Fun damentals. Contributors Judith S. Acosta, formerly Dept. of Animal Science and Industry, Kansas State University, Manhattan, Kansas 66506. Richard Bassette, formerly Dept. of Animal Science and Industry, Kansas State University; present address 811 Kiowa Dr. East, Kiowa, Texas 76240. Rodney J. Brown, Dept. of Nutrition and Food Sciences, Utah State University, Logan, Utah 84322. Richard M. Clark, Dept. of Nutritional Sciences, University of Con necticut, Storrs, Connecticut 06268. Daniel P. Dylewski, Kraft Technical Center, 801 Waukegan Rd., Glen view, Illinois 60025. C. A. Ernstrom, Dept. of Nutrition and Food Sciences, Utah State Uni versity, Logan, Utah 84322. Harold M. Farrell, Jr., USDA, Eastern Regional Research Center, 600 E. Mermaid Lane, Philadelphia, Pennsylvania 19118. Joseph F. Frank, Dept. of Animal and Dairy Science, University of Georgia, Athens, Georgia 30602. Virginia H. Holsinger, USDA, Eastern Regional Research Center, 600 E. Mermaid Lane, Philadelphia, Pennsylvania 19118. Robert Jenness, formerly Dept. of Biochemistry, University of Minnesota; present address 1837 Corte del Ranchero, Alamogordo, New Mexico 88310. Robert G. Jensen, Dept. of Nutritional Sciences, University of Con necticut, Storrs, Connecticut 06268. Mark E. Johnson, Dept. of Food Science, University of Wisconsin, Madison, Wisconsin 53706. Thomas W. Keenan, Dept. of Biochemistry and Nutrition, Virginia Po lytechnic Institute and State University, Blacksburg, Virginia 24061. Mark Keeney, Dept. of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742. vii viii CONTRIBUTORS Elmer H. Marth, Dept. of Food Science, University of Wisconsin, Madison, Wisconsin 53706. Ian H. Mather, Dept. of Animal Sciences, University of Maryland, Col lege Park, Maryland 20742. Lois D. McBean, National Dairy Council, 6300 N. River Road, Rosem ont, Illinois 60018. Charles V. Morr, Dept. of Food Science, Clemson University, Clemson, South Carolina 29631. Ronald L. Richter, Dept. of Animal Science, Texas A&M University, College Station, Texas 77843. John W. Sherbon, Dept. of Food Science, Cornell University, Ithaca, New York 14853. Elwood W. Speckmann, National Dairy Council, 6300 N. River Road, Rosemont, Illinois 60018. John L. Weihrauch, USDA, Human Nutrition Information Service, Federal Center Building, Hyattsville, Maryland 20782. Robert McL. Whitney (deceased), Food Science Dept., University of Illinois, Urbana, Illinois 61801. Noble P. Wong, USDA, Beltsville Agricultural Research Center, Belts ville, Maryland 20705. Preface Fundamentals of Dairy Chemistry has always been a reference text which has attempted to provide a complete treatise on the chemistry of milk and the relevant research. The third edition carries on in that format which has proved successful over four previous editions (Fun damentals of Dairy Science 1928, 1935 and Fundamentals of Dairy Chemistry 1965, 1974). Not only is the material brought up-to-date, indeed several chapters have been completely re-written, but attempts have been made to streamline this edition. In view of the plethora of research related to dairy chemistry, authors were asked to reduce the number of references by eliminating the early, less significant ones. In addition, two chapters have been replaced with subjects which we felt deserved attention: "Nutritive Value of Dairy Foods" and "Chemistry of Processing." Since our society is now more attuned to the quality of the food it consumes and the processes necessary to preserve that quality, the addition of these topics seemed justified. This does not minimize the importance of the information in the deleted chapters, "Vitamins of Milk" and "Frozen Dairy Products." Some of the mate rial in these previous chapters has been incorporated into the new chapters; furthermore, the information in these chapters is available in the second edition, as a reprint from ADSA (Vitamins in Milk and Milk Products, November 1965) or in the many texts on ice cream manufac ture. Originally, Fundamentals of Dairy Science (1928) was prepared by members of the Dairy Research Laboratories, USDA. Over the years, the trend has changed. The present edition draws heavily from the ex pertise of the faculty and staff of universities. Ten of the 14 chapters are written by authors from state universities, three from ARS, USDA, and one from industry. It seems fitting that this is so. The bulk of future dairy research, if it is to be done, appears destined to be accomplished at our universities. Hopefully the chapter authors have presented appropriate material and in such a way that it serves best the principal users of this book, their students. As universities move away from specific product tech nology and food technology becomes more sophisticated, a void has ix x PREFACE been created where formerly a dairy curriculum existed. It is hoped that this edition of Fundamentals of Dairy Chemistry which incorpo rates a good deal of technology with basic chemistry can help fill this void. Preparation of this volume took considerably longer than antici pated. The exigencies of other commitments took its toll. Originally the literature was supposed to be covered to 1982 but many of the chapters have more recent references. I wish to acknowledge with appreciation the contribution made by the chapter authors and the associate editors. Obviously without their assistance, publication of this edition would not have been possible. Dr. Jenness was responsible for Chapters 1, 3,8, and 9; Dr. Keeney, Chapters 4, 5, and 10; Dr. Marth, Chapters 2, 13, and 14; and Dr. Wong, Chapters 6, 7, 11 and 12. Contents Preface / ix 1. Composition of Milk, Robert Jenness / 1 2. Composition of Milk Products, Richard Bassette and Judith S. Acosta / 39 3. Proteins of Milk, Robert McL. Whitney / 81 4. Lipid Composition and Properties, Robert G. Jensen and Richard M. Clark / 171 5. Lipids of Milk: Deterioration, John L. Weihrauch / 215 6. Lactose, Virginia H. Holsinger / 279 7. Nutritive Value of Dairy Foods, Lois D. McBean and Elwood W. Speckmann / 343 8. Physical Properties of Milk, John W. Sherbon / 409 9. Physical Equilibria: Proteins, Harold M. Farrell / 461 10. Physical Equilibria: Lipid Phase, Thomas W. Keenan, Ian H. Mather, and Daniel P. Dylewski / 511 11. Milk Coagulation and Protein Denaturation, Rodney J. Brown / 583 12. Milk-Clotting Enzymes and Cheese Chemistry, PART I-Milk Clotting Enzymes, Rodney J. Brown and C. A. Emstrom / 609 PART II-Cheese Chemistry, Mark E. Johnson / 634 13. Fermentations, Joseph F. Frank and Elmer H. Marth / 655 14. Chemistry of Processing, Charles V. Morr and Ronald L. Richter / 739 . Index / 767 1 Composition of Milk Robert Jenness Milk is secreted by all species of mammals to supply nutrition and immunological protection to the young. It performs these functions with a large array of distinctive compounds. Interspecies differences in the quantitative composition of milk (Jenness and Sloan 1970) prob ably reflect differences in the metabolic processes of the lactating mother and in the nutritive requirements of the suckling young. Human beings consume large amounts of milk of a few species be sides their own. The principal ones are cows, water buffaloes, goats, and sheep, which furnish annually about 419,26, 7.2, and 7.3 million metric tons of milk, respectively, for human consumption (FAO Pro duction Yearbook 1979). This chapter, and indeed this entire volume, deals primarily with the milk of western cattle-Bos taurus. References to reviews concerning milk of other important species are: Indian cat tie-B. indicus (Basu et at. 1962); water buffalo-Bubalus bubalis (Lax minarayan and Dastur 1968); goat-Capra hircus (Parkash and Jen ness 1968; Jenness 1980; Ramos and Juarez 1981); sheep-Ovis aries (Ramos and Juarez 1981); and humans-Homo sapiens (Macy et al. 1953; Jenness 1979; Blanc 1981; Gaull et al. 1982; Packard 1982). In the United States, milk is defined for commercial purposes as the lacteal secretion, practically free from colostrum, obtained by the com plete milking of one or more healthy cows, which contains not less than 8.25% of milk-solids-not-fat and not less than 3.25% milk fat. Minimal standards in the various states may vary from 8.0 to 8.5% for milk solids-not-fat and from 3.0 to 3.8% for milk fat (U.S. Dept. Agr. 1980). CONSTITUENTS OF MILK Milk consists of water, lipids, carbohydrates, proteins, salts, and a long list of miscellaneous constituents. It may contain as many as 105 differ ent kinds of molecules. Refinement of qualitative and quantitative techniques continues to add new molecular species to the list. The con stituents fall into four categories: N. P. Wong et al. (eds.), Fundamentals of Dairy Chemistry 1 © Van Nostrand Reinhold Company Inc. 1988