Manufacturing Yogurt and Fermented Milks E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 992

Veröffentlichungsjahr: 2013

Beschreibung

Melding the hands-on experience of producing yogurt and fermented milks over four decades with the latest in scientific research in the dairy industry, editor Chandan and his associate editors have assembled experts worldwide to writeManufacturing Yogurt and Fermented Milks, 2nd Edition. This one-of-a-kind resource gives a complete description of the manufacturing stages of yogurt and fermented milks from the receipt of raw materials to the packaging of the products.

Information is conveniently grouped under four categories:

· Basic background—History and consumption trends, milk composition characteristics, dairy processing principles, regulatory requirements, laboratory analysis, starter cultures, packaging, and more

· Yogurt manufacture—Fruit preparations and flavoring materials, ingredients, processing principles, manufacture of various yogurt types, plant cleaning and sanitizing, quality assurance, and sensory analysis

· Manufacture of fermented milks—Procedure, packaging and other details for more than ten different types of products

· Health benefits—Functional foods, probiotics, disease prevention, and the health attributes of yogurt and fermented milks

All manufacturing processes are supported by sound scientific, technological, and engineering principles. 

Leseprobe

Contents

List of contributors

Preface to the second edition

Preface to the first edition

Part I Basic background

1 History and consumption trends

1.1 Overview of the world dairy industry

1.2 Milk production in the USA

1.3 Production of dairy foods in the USA

1.4 Fermented/cultured dairy products

1.5 Occurrence and consumption of fermented milks in various regions

1.6 Major commercial fermented milks

1.7 Scandinavian fermented milks

1.8 Russian and Eastern European fermented milks

1.9 Middle Eastern fermented milks

1.10 South Asian fermented milks

2 Milk composition, physical and processing characteristics

2.1 Introduction

2.2 Milk composition

2.3 Milk components and processing characteristics

2.4 Physicochemical properties of milk

3 Regulatory requirements for milk production, transportation and processing

3.1 Introduction

3.2 From farm to factory

3.3 History of milk safety

3.4 United States Public Health Grade “A” Milk Safety Program

3.5 Inspection of milk safety

3.6 Farm requirements

3.7 Milk transportation

3.8 Processing plant

3.9 Hazard Analysis and Critical Control Point System

3.10 Standards and regulations

3.11 Milk pricing—US Federal Milk Marketing Orders

4 Regulations for product standards and labeling

4.1 US Code of Federal Regulations

4.2 US product standards of identity

4.3 Fermented milk and milk products

4.4 Stayed provisions

4.5 Frozen yogurt

4.6 Food additives and packaging

4.7 Labeling

4.8 Codex Standards and definitions for fermented-milk products

5 Principles of dairy processing

5.1 Introduction

5.2 From farm to factory

5.3 Storage of raw milk

5.4 Overview of processing equipment in a dairy plant

5.5 Centrifugal operations

5.6 Thermal-processing systems

5.7 Homogenization

5.8 Membrane technology

5.9 Conclusion

6 Starter cultures for yogurt and fermented milks

6.1 Introduction

6.2 Starter functions

6.3 Factors affecting starter performance

6.4 Microorganisms used in starters for cultured dairy products

6.5 Genus Lactococcus

6.6 Comments on Cit+ Lactococcus lactis ssp. lactis

6.7 Genus Leuconostoc

6.8 Genus Streptococcus

6.9 Genus Lactobacillus

6.10 Genus Bifidobacterium

6.11 Starter-culture production

6.12 Miscellaneous starters

6.13 Literature

7 Fermented dairy packaging materials

7.1 Introduction

7.2 Fundamentals of packaging

7.3 Packaging materials

7.4 Interactions between product and packaging

7.5 The package in product distribution

7.6 Graphic design and assessment

7.7 Economics of packaging

7.8 Regulation

7.9 Packaging and the environment

7.10 Packaging for yogurt and fermented dairy products

7.11 Future trends

8 Milk and milk-based ingredients

8.1 Introduction

8.2 Composition and specifications

8.3 Performances in yogurt formulation

8.4 Conclusion

Part II Manufacture of yogurt

9 Yogurt: fruit preparations and flavoring materials

9.1 Introduction

9.2 Fruit as a raw material for yogurt preparations

9.3 Processing of fruit for use in yogurt fruit preparations

9.4 Formulation of fruit preparations

9.5 Processing yogurt fruit preparations

9.6 Packaging of fruit preparations

9.7 Acknowledgment

10 Ingredients for yogurt manufacture

10.1 Introduction

10.2 Dairy ingredients and their origin

10.3 Sweeteners

10.4 Stabilizers

11 Principles of yogurt processing

11.1 Introduction

11.2 Mix preparation

11.3 Heat treatment

11.4 Homogenization

11.5 Yogurt starter

11.6 Changes in milk constituents during yogurt production

12 Manufacture of various types of yogurt

12.1 Introduction

12.2 General manufacturing procedures applicable to all categories

12.3 Yogurt types, styles, subcategories and definitions

12.4 Market statistics on the yogurt trade

12.5 Manufacturing process for major yogurt categories

12.6 General manufacturing procedures for major types of yogurt

12.7 Post-culturing heat treatment

13 Greek-style yogurt and related products

13.1 Introduction

13.2 Greek-style yogurt

13.3 Chakka and shrikhand

13.4 Quarg and fromage frais

13.5 Mishti doi/dahi

14 Plant cleaning and sanitization

14.1 Introduction

14.2 Cleaning

14.3 Sanitization

14.4 Phage control

14.5 A final thought

15 Yogurt plant: quality assurance

15.1 Introduction

15.2 Regulatory obligations

15.3 Quality-control programs

15.4 National Yogurt Association criteria for live- and active-culture yogurts

15.5 Specification program

16 Sensory analysis of yogurt

16.1 Introduction

16.2 Sensory-analysis techniques

16.3 Sensory analysis of yogurt

16.4 Conclusions

Part III Manufacture of fermented milks

17 Cultured buttermilk

17.1 Introduction

17.2 Milk supply

17.3 Processing of milk

17.4 Buttermilk starter culture

17.5 Breaking, cooling, bottling and distribution

Acknowledgment

18 Cultured/sour cream

18.1 Early history

18.2 Present standards

18.3 Sour-cream products

19 Other fermented and culture-containing milks

19.1 Introduction

19.2 Dahi

19.3 Kefir

19.4 Koumiss

19.5 Acidophilus milk and sweet acidophilus milk

19.6 Probiotic milks

19.7 Bulgarian milk

19.8 Skyr

19.9 Viili

19.10 Kurut

Part IV Health benefits

20 Functional foods and disease prevention

20.1 Introduction

20.2 Functional foods

20.3 Bioactive dairy ingredients

20.4 Milk fat

20.5 Probiotics

20.6 Fortification

20.7 Physiologically active ingredients

21 Health benefits of yogurt and fermented milks

21.1 Introduction

21.2 Yogurt and other fermented milks

21.3 Health benefits of fermented milks

22 Probiotics and fermented milks

22.1 Introduction

22.2 Taxonomy of lactic-acid bacteria

22.3 Probiotic bacteria

22.4 Selection criteria for probiotics

22.5 Health benefits of Lactobacillus acidophilus and bifidobacteria

22.6 Conclusion

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Index

Dedication

We dedicate this book to Professor Khem M. Shahani, who inspired, mentored and guided both of the editors of this book while they were graduate students at the University of Nebraska–Lincoln. In our opinion, Dr Shahani truly belonged to the distinguished world class of pioneers in conducting sound scientific studies on the beneficial health attributes of consuming live and active yogurt containing probiotics, as exemplified by Lactobacillus acidophilus, other lactobacilli and bifidobacteria. The groundbreaking work of his research laboratory at the University of Nebraska–Lincoln elucidated how yogurt culture containing active lactase enzyme helps in the digestion of lactose in lactose-malabsorbing individuals. Other research work showed a reduction of serum cholesterol as a result of consumption of acidophilus products. His research team demonstrated immune-system enhancement by the consumption of probiotic cultures. Furthermore, it provided evidence for the suppression of pathogenic bacteria (such as Heliobacter pylori, E. coli, Salmonella and Staphylococcus aureus) by Lactobacillus acidophilus. We were indeed fortunate to have worked on some of the areas mentioned above under Dr Shahani’s tutelage and direction.

Prior to Dr Shahani’s outstanding research findings, the scientific and medical community did not generally recognize or appreciate the health merits of live and active yogurt bacteria and probiotic cultures. With the help of Dr Shahani, compelling scientific data made a profound impact on the philosophy of health maintenance and improvement. The results of his probiotic research, as well as his numerous presentations to international audiences, brought credibility and convinced many clinicians around the world regarding the outstanding health benefits of consuming live and active probiotic cultures. In this regard, we believe that Dr Shahani initiated a movement to bring the science of probiotics and their use directly to consumers concerned with improving their health.

We dedicate this book to the memory of Dr Shahani for his outstanding pioneering work on yogurt and probiotic cultures.

Ramesh C. Chandan and Arun Kilara

This edition first published 2013 © 2013 by John Wiley & Sons, IncFirst edition published 2006 © 2006 by Blackwell Publishing

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Library of Congress Cataloging-in-Publication Data

Manufacturing yogurt and fermented milks / edited by Ramesh C. Chandan, Global Technologies, Inc., Coon Rapids, MN, Arun Kilara, Nutri+Food Business Consulting, Chapel Hill, NC. – Second edition. pages cm Includes bibliographical references and index.

ISBN 978-1-118-48130-1 (ebook) – ISBN 978-1-118-48131-8 (mobi) – ISBN 978-1-118-48132-5 (epub) – ISBN 978-1-118-48133-2 (ebook/epdf) – ISBN 978-1-119-96708-8 (hardback : alk. paper) 1. Yogurt. 2. Fermented milk. 3. Dairy processing. 4. Food industry and trade. I. Chandan, Ramesh C. II. Kilara, Arun.

SF275.Y6M36 2013 637′.146–dc23

2012030221

A catalogue record for this book is available from the British Library.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Cover image: © WavebreakmediaMicro - Fotolia.comCover design by Meaden Creative

List of contributors

Dennis BogartRandolph Associates, Inc.Birmingham, Alabama,USABill BornDairy Consultant (retired from Dean Foods Co.)Rockford, Illinois,USAGuillaume Brisson, PhDRiddet InstituteMassey UniversityNew ZealandAaron L. Brody, PhDPresident & CEOPackaging/Brody, Inc.Duluth, Georgia,USARamesh C. Chandan, PhDConsultantGlobal Technologies, Inc.Coon Rapids, Minnesota, USAMaryAnne Drake, PhDDepartment of Food ScienceNorth Carolina State UniversityRaleigh, North Carolina, USACary P. FryeVice-President, Regulatory AffairsInternational Dairy Foods AssociationWashington, DC, USAYonca Karagül-Yüceer, PhDAssistant ProfessorCanakkale Onsekiz Mart UniversityDepartment of Food EngineeringTerzioglu CampusTurkeyArun Kilara, PhDPrincipal, Nutri+Food Business ConsultingChapel Hill, North Carolina,USAKevin O’RellSenior Vice President, Operations/R&DThe YoCrunch Company, LLCRosemont, Illinois,USANagendra P. Shah, PhD, FAIFSTProfessor of Food ScienceThe University of Hong KongPokfulam Road, Hong KongHarjinder Singh, PhD, FRSNZFIAFoST DirectorRiddet InstituteMassey UniversityNew ZealandIsabelle Sodini, PhDPortocork AmericaNapa, California,USAPhillip S. Tong, PhDDirector, Dairy Products Technology CenterCalifornia Polytechnic State UniversitySan Luis Obispo, California,USAEbenezer R. Vedamuthu, PhDConsultantCorvallis, Oregon,USACharles H. White, PhDRandolph Associates, Inc.Birmingham, Alabama, USA

Preface to the second edition

The first edition of Manufacturing Yogurt and Fermented Milks was published in 2006. The book was well received and it is gratifying to note that the publisher wants to bring out the second edition. A number of developments have taken place since the first edition was ­published. Yogurt continues to be one of the fastest-growing food categories in the USA as well as in the rest of the world. New introductions in the marketplace include health-oriented smoothies/drinks, yogurts containing probiotics and prebiotics, yogurts with specific strains claiming digestive and immune-enhancing benefits, uniquely textured Greek-style yogurt and yogurt fortified with vitamins A and D, calcium, fiber and other health-enhancing ingredients. Greek-style yogurt, with its new texture and attractive consumer-positive attribute (twice as much protein), now commands nearly one-quarter of the total yogurt market in the USA. Similarly, frozen yogurt has taken hold, and new offerings include probiotics and health-oriented ingredients.

The second-edition chapters have been updated to highlight the changes since the first edition. More importantly, the advances in regulatory requirements for milk production, transportation and processing in the USA have been discussed. Accordingly, regulatory standards for milk, yogurt and fermented milks which have been developed and adopted by the US Food and Drug Administration (FDA) and the Codex Alimentarious Commission have been included. The new edition also deals with the extensive changes that have occurred in the regulations for product standards and labeling.

The chapter on the principles of dairy processing (Chapter 5) has been updated with respect to membrane processing technology. New developments in starter technology with respect to new cultures (mild, gel-forming) and probiotic strains have been discussed. The dairy-packaging chapter (Chapter 7) has also been updated.

Recent developments relative to fruit preparations and flavoring materials for yogurt ­manufacture have been added. The current practices of using milk and milk-based ingredients have been incorporated. In particular, newer ingredients (milk-protein concentrate and other nondairy ingredients) have been included. The chapters on the principles of yogurt processing have been updated to include developments in Greek-style yogurt, stevia-based high-intensity sweeteners, smoothies/yogurt drinks and probiotic yogurts. A new chapter on Greek-style and other concentrated yogurt products (Chapter 13) has been added in recognition of the fact that currently, almost 30% of the yogurt market in the USA consists of Greek-style yogurt. The chapters on plant cleaning (Chapter 14) and quality assurance (Chapter 15) have been brought up to date.

Other chapters have been revised to include developments and advancements in the areas of probiotics and prebiotics and their health attributes, as well as possible health claims relative to their consumption.

The book is intended to focus primarily on the yogurt and fermented-milks industry in North America in general and the USA in particular. The material on scientific principles and the basis of yogurt technology has universal applications throughout the world. It is hoped that the updated second edition will continue to be useful for university students in dairy food science and technology and food-industry personnel involved in production, research and development, quality control/assurance and purchasing.

Ramesh C. Chandan, Minneapolis, MinnesotaArun Kilara, Chapel Hill, North Carolina

Preface to the first edition

Fermented dairy products other than cheeses have been consumed around the world for ­thousands of years. Nevertheless, their industrial production is relatively a new innovation. Yogurt has emerged as an outstanding new product of recent times. It has occupied a very significant position of consumer acceptance and growth in North America and throughout the world. In the United States, yogurt, buttermilk, sour cream, and probiotic drinks have become multibillion dollar industry. The yogurt market continues to grow on an annual basis.

The literature on yogurt and fermented milks is vast and diverse. It encompasses the basic and fundamental aspects as well as applied and practical facets of the industry. This book is intended to disseminate the applied and practical aspects. Some basic science is included only to facilitate understanding of the practice of manufacturing yogurt and fermented milks. Overall, our objective is not to provide fundamental information. Instead, attempts have been made to deal with the application of the science of yogurt and fermented milks to their manufacture and emphasize the practices in vogue in the industry.

As mentioned above, the book is dedicated to the manufacture of yogurt and fermented milks. In view of the multidisciplinary nature and continued fast developments in the ­technology and packaging of fermented milks, the book has multiple authors. The authors drawn from the industry and academia are experts in their respective fields. Many authors have utilized their life-long experience in the product development, quality assurance, and manufacture of yogurt and fermented milks in their contributed chapters. Their contribution to the writing of the book makes this book unique and the first of its kind in the literature. From a comprehension and readability standpoint, an effort has been made to make the book reader-friendly.

The book is organized into twenty-two chapters and divided into four parts. Part I covers the basic background with eight chapters. The objective is to prepare the reader for the manufacturing of yogurt and fermented milks by providing relevant information on product trends, regulatory aspects, dairy processing technologies, packaging techniques, starter ­cultures use, and laboratory analysis.

Part II is devoted to the manufacture of yogurt. This part also consists of eight chapters. It includes raw materials, namely dairy and dairy-based ingredients, fruits and flavors, stabilizers, sweeteners (nutritive and high intensity), principles of yogurt processing, types of yogurt products on the market and their manufacturing techniques, quality control procedures, ­sensory evaluation of yogurt, and plant cleaning and sanitizing programs. The formulation, regulatory aspects, labeling, processing equipment, and packaging operations of various products have been included.

Part III contains three chapters detailing the manufacturing technology of cultured ­buttermilk, sour cream, and miscellaneous fermented milks popular throughout the major regions of the world. It also includes culture-containing milks that are not cultured and retain the sensory characteristics of milk but concomitantly provide beneficial probiotic cultures to the consumer.

Part IV deals with the overall health benefits of yogurt and fermented milks. This topic has assumed much interest in view of consumer perception of health promotion attributed to functional foods like yogurt and fermented milks. This part brings to the reader a brief review of our understanding of both perceived and real benefits. A concise account of the scientific and clinical evidence associated with the benefits of consuming yogurt and milks containing probiotic cultures, prebiotics and synbiotics has been reviewed. This is a timely subject because new products with health claims are increasingly appearing in the market. We feel that this is the direction for future growth of the industry engaged in yogurt and fermented milks manufacture.

This book is the culmination of efforts to provide a systematic and relatively simplified version of the information available on significant aspects of manufacturing yogurt and ­fermented milks. It is intended as a text book to be used by upper undergraduate university students of dairy and food science to learn the theory and practice of technology associated with the manufacture of yogurt and fermented milks. Graduate students should find the book useful as a reference book to obtain information on applied science and technology of yogurt and fermented milks. The industrial bias of the book should appeal to practitioners of food science and technology in the food industry. In this case, it would provide a ready reference material for plant operators, personnel performing functions in quality control/assurance, and research and development. The book should also be helpful for the food industry ­personnel engaged in taking purchasing decisions. Since the book conveys collated practical information on yogurt and fermented milks in entirety, it should be useful as a text book to the instructors and participants of the industry-oriented short courses in cultured dairy products.

We acknowledge the worldwide contribution of all the scientists, technologists and ­engineers who have established modern principles for the manufacture of yogurt and ­fermented milks to provide the consumer with a truly functional family of foods that furnish vital dairy nutrients as well as unique, wholesome and healthy products.

Ramesh C. Chandan, Minneapolis, MinnesotaCharles H. White, Mississippi State, MississippiArun Kilara, Chapel Hill, North CarolinaY.H. Hui, Sacramento, California

Part I

Basic background

1  History and consumption trends

Ramesh C. Chandan

Global Technologies, Inc., Coon Rapids, Minnesota, USA

1.1 Overview of the world dairy industry

According to the UN Food and Agriculture Organization (FAO, 2011), the world production of milk in 2009 was 701.4 million metric tons (MT). This was estimated to increase to 713.6 million MT in 2010 and to 727.6 million MT in 2011. India is the largest producer of milk (including milk of cows and water buffaloes) in the world, with an estimated 121.7 ­million MT in the year 2011.

The 2009 world production of cow milk in the selected countries shown in Table 1.1 was 432.7 million MT. The documented number of cows was 129 296 thousand heads. Individual cow-milk yield varies widely around the world. In 2009, the USA and Japan were the most efficient milk producers, with 9.33 MT/cow, followed by Canada, with a yield of 8.46 MT per cow. Milk yield was lowest in India (1.13 MT/head), followed by Brazil (1.67 MT/head) and Mexico (1.70 MT/head).

1.2 Milk production in the USA

The trend in the last decade indicates a noticeable decrease in dairy-cow population, from 9.151 million heads in the year 1998 to 9.117 million heads in 2010 (Table 1.2). In the year 2010, 9.117 million cows produced 87.46 million MT (192 819 million pounds) of milk (IDFA, 2011). Table 1.2 also shows that during the period 1998–2010 there is a steady increase in milk production per cow, from 7.79 MT (17 185 pounds) to 9.59 MT (21 149 pounds). Concomitantly, milk production in the USA registered an increase from 76.33 ­million MT (157 262 million pounds) to 87.46 million MT (192 819 million pounds). Approximately 20% of the world’s milk is produced in the USA. The American dairy farm has been able to achieve its current milk output through the application of scientific and management advancements in milk production. On the dairy farm, selection of dairy cows, their breeding, and judicious use of balanced feed rations have been instrumental in increasing milk output per cow. As a result of continuous efficiencies in milk production at the farm, milk production per cow has doubled in the last 30 years. California continues to be the leading milk-producer state, followed by Wisconsin, New York, Idaho and Pennsylvania.

Table 1.1 World milk production in 2009. Adapted from USDA (2011a) and DairyCo (2011).

Table 1.2 Milk production in the USA. Adapted from IDFA (2011).

1.3 Production of dairy foods in the USA

At dairy farms, modern milking and milk-handling equipment, including automated milking systems, have improved the speed of cleaning, sanitizing, cooling and delivering good-­quality raw milk to processing plants. The USA has the distinction of being the largest ­processor of milk and dairy products in the world. Advanced processing and packaging technologies ensure efficient delivery and a long shelf-life of high-quality milk products, including yogurt and fermented milks. Currently, the US dairy industry is valued at 110 ­billion US dollars (USD). Approximately 30% of the US milk produced on the farm is processed into fluid milk and cream products (Schultz, 2011b). Fluid milk products include whole milk (3.25% fat), reduced-fat milk (2% fat), low-fat milk (1% fat), nonfat milk (<0.5% fat), half and half (10.5 to <18% fat), light cream (18 to <30% fat), light whipping cream (30 to <36% fat), heavy cream (not less than 36% fat), cultured milk (3.25% fat), cultured reduced-fat milk (2% fat), cultured low-fat milk (1% fat), cultured nonfat milk (<0.5% fat) (cultured buttermilk), yogurt (3.25% fat), reduced-fat yogurt (2% fat), low-fat yogurt (1% fat), nonfat yogurt (<0.5% fat) and cottage cheese (4, 2, 1 or <0.5% fat).

The remaining 70% of farm milk is used in dairy manufacturing plants, where it is transformed into more than 300 varieties and styles of cheese, 100 flavors of ice cream, frozen desserts and frozen yogurt. In addition, dairy plants produce an array of flavored milk, ­ranging from fat-free to full-fat, butter, sweetened condensed milk, evaporated milk, dry milk, lactose, whey products and cultured products such as sour cream and dips, buttermilk and yogurt drinks/smoothies. According to Schultz (2011a), Wisconsin has the most dairy plants (210), followed by New York state (108) and California (106). The dairy-processing industry has demonstrated several packaging and marketing innovations in competing aggressively for consumer food dollar share.

The products manufactured in the years 2006–2010 and their volumes are shown in Table 1.3. Butter production increased from 0.66 million MT (1448 million pounds) to 0.71 million MT (1564 million pounds), whereas natural cheese registered an increase from 4.32 million MT (9525 million pounds) to 4.73 million MT (10 436 million pounds). Process cheese declined from 1.06 million MT (2349 million pounds) to 0.96 million MT (­2124 million pounds). Frozen desserts, including ice cream, whole milk, reduced-fat and low-fat some increase in volume. In the fermented-dairy-products category, refrigerated yogurt ­displayed explosive growth, from 1.50 million MT (3301 million pounds) in 2006 to 1.90 ­million MT (4181 million pounds) in 2010. However, sour cream and dips showed a relatively steady production volume (0.57 million MT (1256 million pounds) to 0.59 million MT (1292 million pounds)), whereas buttermilk production declined from 0.23 million MT (504 million pounds) to 0.21 million MT (473 million pounds).