Handbook of Drying for Dairy Products

Handbook of Drying for Dairy Products is a complete guide to the field′s principles and applications, with an emphasis on best practices for the creation and preservation of dairy–based food ingredients. It is a comprehensive introduction to the fundamentals of drying dairy products and contains the most up–to–date industry research. The chapters detail techniques and results for a variety of different methods, including drum drying, spray drying, freeze drying, spray–freeze drying, and hybrid drying. They also address the effect of different drying techniques on the nutritional profile of dairy products and the ways these can be optimized using computer modelling. With essential information for dairy science academics as well as technologists active in the dairy industry, this is a cutting–edge examination of a burgeoning area within food science and engineering.

Contributors xiii

About the editor xv

Preface xvii

Acknowledgments xix

1 Introduction to Drying 1
C. Anandharamakrishnan

1.1 Introduction 1

1.2 Fundamental principles of drying: the concept of simultaneous heat and mass transfer 2

1.3 The drying curve 9

1.4 Stages of drying 9

1.5 Techniques for the drying of dairy products 12

1.6 Conclusion 13

References 13

2 Dried Dairy Products and their Trends in the Global Market 15
Aadinath, T. Ghosh, P.H. Amaladhas and C. Anandharamakrishnan

2.1 Introduction 15

2.2 Milk powders and dried milk products 16

2.3 World market dynamics 18

References 21

3 Techniques for the Preconcentration of Milk 23
I. Roy, A. Bhushani and C. Anandharamakrishnan

3.1 Introduction 23

3.2 Need for preconcentration 23

3.3 Concentration methods 25

3.4 Thermal methods 25

3.5 Non–thermal methods 30

3.6 Conclusion 37

References 37

4 Drum Drying 43
P. Karthik, N. Chhanwal and C. Anandharamakrishnan

4.1 Introduction 43

4.2 Drum–drying process 44

4.3 Types of drum dryers 46

4.4 Classification of the feeding method 49

4.5 Operating parameters 51

4.6 Advantages and disadvantages of drum/roller drying 54

4.7 Conclusion 54

References 55

5 Spray Drying 57
S. Padma Ishwarya and C. Anandharamakrishnan

5.1 Introduction 57

5.2 Spray drying: principle of operation 57

5.3 Characteristics of spray–dried dairy powders 74

5.4 Handling spray–drying processing problems 77

5.5 Applications of spray drying for the production of dried milk and milk products 79

5.6 Conclusion 84

References 88

6 Freeze Drying 95
A. Bhushani and C. Anandharamakrishnan

6.1 Introduction 95

6.2 Steps in freeze drying 95

6.3 Merits of freeze drying over other drying techniques 100

6.4 Heat and mass transfer in freeze drying 101

6.5 Freeze–drying equipment 103

6.6 Properties influencing the freeze drying of dairy products 106

6.7 Preservation of kefir culture by freeze drying 111

6.8 Microencapsulation of probiotics by freeze drying 112

6.9 Conclusion 115

References 117

7 Spray Freeze Drying 123
S. Padma Ishwarya, C. Anandharamakrishnan and A.G.F. Stapley

7.1 Introduction 123

7.2 SFD process 124

7.3 Applications of SFD in dried dairy products 132

7.4 Advantages and limitations of SFD 144

7.5 Conclusion 144

References 144

8 Optimization of Dairy Product Drying Processes 149
S. Parthasarathi and C. Anandharamakrishnan

8.1 Introduction 149

8.2 Experimental design tools for process optimization 149

8.3 Drying process variables and their influence on process and product quality 156

8.4 Conclusion 170

References 171

9 Computational Fluid Dynamics Modelling of the Dairy Drying Processes 179
J. Gimbun,W.P. Law and C. Anandharamakrishnan

9.1 Introduction 179

9.2 Spray drying 179

9.3 Freeze drying 189

9.4 Spray freeze drying 193

9.5 Conclusions and future scope 196

References 196

10 Physicochemical and Sensory Properties of Dried Dairy Products 203
P.H. Amaladhas and F. Magdaline Eljeeva Emerald

10.1 Introduction 203

10.2 Milk Powder Manufacture 203

10.3 Properties of dairy powders as influenced by drying method 208

10.4 Physical properties 209

10.5 Chemical and sensory properties 218

10.6 Properties of special powders 220

10.7 Conclusion 223

References 223

11 Packaging of Dried Dairy Products 229
R. Gopirajah and C. Anandharamakrishnan

11.1 Introduction 229

11.2 Dairy packaging trends 230

11.3 Forms of packaging materials 231

11.4 Packaging of dried milk products 234

11.5 Developments in packaging techniques 237

11.6 Conclusion 244

References 244

12 Recent Advances in the Drying of Dairy Products 249
M.W.Woo

12.1 Introduction 249

12.2 Typical layout of a dairy spray–drying process 250

12.3 Advances in operating spray dryers 252

12.4 Advances in operating fluidized–bed dryers 261

12.5 Conclusion 263

References 263

13 Industrial Scale Drying of Dairy Products 269
D. Anand Paul

13.1 Introduction 269

13.2 Process flow in a dairy drying plant 270

13.3 Lexicon of industrial–scale drying 272

13.4 Industrial spray drying of dairy products 273

13.5 Industrial drum drying of dairy products 279

13.6 Conclusion 283

References 283

14 Challenges Involved in the Drying of Dairy Powders 287
U. Kiran Kolli

14.1 Introduction 287

14.2 Challenges in the drying of dairy powders 288

14.3 Use of modelling as a tool to solve some challenges 295

14.4 Conclusion 296

References 296

Index 301

About the editor
C. Anandharamakrishnan is Director at the Indian Institute of Crop Processing Technology (IICPT), Thanjavur, India. Before assuming responsibility as Director, IICPT, he was Principal Scientist in the Food Engineering Department of the CSIR Central Food Technological Research Institute, Mysore, India. He has been active in the field of spray drying for the past 10 years, working on the micro– and nanoencapsulation of nutraceuticals and computational fluid dynamics modelling of spray drying. He completed a PhD on spray drying and spray–freeze drying of proteins at Loughborough University, UK.