Handbook of Drying for Dairy Products PDF 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.
Details the techniques and results of drum drying, spray drying, freeze drying, spray-freeze drying, and hybrid drying
Contains the most up-to-date research for optimizing the drying of dairy, as well as computer modelling options
Addresses the effect of different drying techniques on the nutritional profile of dairy products
Provides essential information for dairy science academics as well as technologists active in the dairy industry
Table of Contents
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
1.2.1 Heat transfer during the drying process 2
1.2.1.1 Conduction drying 3
1.2.1.2 Convection drying 4
1.2.1.3 Radiation and dielectric drying 5
1.2.2 Mass transfer during the drying process 6
1.2.2.1 Diffusion mechanism 7
1.2.2.2 Capillary mechanism 8
1.3 The drying curve 9
1.4 Stages of drying 9
1.4.1 Constant rate period 10
1.4.2 Falling rate period 11
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
2.2.1 Primary dairy powders 16
2.2.2 Secondary dairy powders 16
2.3 World market dynamics 18
2.3.1 Production 18
2.3.1.1 Oceania 18
2.3.1.2 India 20
2.3.1.3 European Union 20
2.3.1.4 Argentina 20
2.3.2 Consumption 20
2.3.2.1 Algeria 20
2.3.2.2 Indonesia 21
2.3.2.3 China 21
2.3.2.4 Mexico 21
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
3.2.1 Skim milk 24
3.2.2 Whey powders and infant formula 24
3.3 Concentration methods 25
3.4 Thermal methods 25
3.4.1 Evaporation 25
3.4.1.1 Single-effect recirculation evaporator 25
3.4.1.2 Multiple-effect evaporator 26
3.4.1.3 Falling-film evaporator 27
3.4.1.4 Plate evaporator 28
3.4.1.5 Horizontal tube evaporator 30
3.4.1.6 Mechanical film evaporator 30
3.4.1.7 Low-temperature evaporator 30
3.5 Non-thermal methods 30
3.5.1 Freeze concentration 30
3.5.2 Membrane separation techniques 32
3.5.2.1 Microfiltration 34
3.5.2.2 Ultrafiltration 35
3.5.2.3 Reverse osmosis 37
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
4.2.1 Effect of operating parameters on product quality and the capacity of the drum dryer 45
4.3 Types of drum dryers 46
4.3.1 Single-drum dryers 46
4.3.2 Double-drum dryers 47
4.3.3 Twin-drum dryers 47
4.3.4 Vacuum-drum dryers 48
4.3.5 Enclosed-drum dryers 49
4.4 Classification of the feeding method 49
4.4.1 Single- and multiple-roll feed 49
4.4.2 Nip feed 49
4.4.3 Dip feed 49
4.4.4 Spray feed 49
4.4.5 Splash feed 50
4.5 Operating parameters 51
4.5.1 Important operational conditions in the drum drying of milk 52
4.6 Advantages and disadvantages of drum/roller drying 54
4.7 Conclusion 54
References 55
5 SprayDrying 57 S. Padma Ishwarya and C. Anandharamakrishnan
5.1 Introduction 57
5.2 Spray drying: principle of operation 57
5.2.1 Atomization 59
5.2.1.1 Rotary atomizers 60
5.2.1.2 Pressure nozzle atomizers 62
5.2.1.3 Twin-fluid atomizers 62
5.2.1.4 Monodisperse droplet generators 63
5.2.2 Droplet–drying air interaction and moisture evaporation 65
5.2.3 Particle separation 72
5.3 Characteristics of spray-dried dairy powders 74
5.3.1 Rehydration 74
5.3.2 Particle size and shape parameters 75
5.4 Handling spray-drying processing problems 77
5.4.1 Stickiness 77
5.4.2 Thermal denaturation of proteins 79
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
6.2.1 Freezing 96
6.2.2 Primary or sublimation drying 99
6.2.3 Secondary or desorption drying 100
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
6.6.1 Milk 106
6.6.2 Lactose 109
6.7 Preservation of kefir culture by freeze drying 111
6.8 Microencapsulation of probiotics by freeze drying 112
6.8.1 Probiotics 112
6.8.2 Need for microencapsulation 113
6.8.3 Cell viability issues associated with freeze drying 113
6.8.4 Characteristics of microencapsulated probiotic cells 114
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
7.2.1 Atomization 125
7.2.2 Freezing 126
7.2.2.1 Spray freezing into vapour 127
7.2.2.2 Spray freezing into vapour over liquid 127
7.2.2.3 Spray freezing into liquid 129
7.2.3 Freeze drying 130
7.2.3.1 Vacuum freeze drying 130
7.2.3.2 Atmospheric SFD and atmospheric spray fluidized-bed freeze drying 131
7.2.3.3 Sub-atmospheric pressure SFD 132
7.3 Applications of SFD in dried dairy products 132
7.3.1 SFD of whole milk and skim milk 133
7.3.2 SFD of whey protein 135
7.3.3 SFD for microencapsulation of probiotics 140
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
8.2.1 Response surface methodology 149
8.2.1.1 Advantages of RSM 151
8.2.1.2 Limitations of RSM 151
8.2.2 Artificial neural networks 151
8.2.2.1 Feed-forward neural network 152
8.2.2.2 Learning process of an ANN 153
8.2.2.3 Optimization of process parameters 154
8.2.3 Finite element and finite volume methods 154
8.2.3.1 Finite element method 155
8.2.3.2 Finite volume method 155
8.3 Drying process variables and their influence on process and product quality 156
8.3.1 Drum drying 157
8.3.1.1 Heat and mass transfer 157
8.3.2 Spray drying 158
8.3.2.1 Exergy efficiency 160
8.3.2.2 Atomization 160
8.3.3 Freeze drying 161
8.3.3.1 Temperature measurement 162
8.3.3.2 Computational modelling 164
8.3.4 Spray freeze drying 169
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
9.2.1 Spray-drying process 179
9.2.2 Flow field simulation 180
9.2.2.1 Steady or unsteady approach 181
9.2.2.2 Turbulence modelling 182
9.2.3 Discrete phase modelling 183
9.2.4 Wall deposition and the particle build-up model 186
9.2.5 Particle interaction 186
9.2.6 Validation and issues of CFD simulation 189
9.3 Freeze drying 189
9.3.1 Modelling of freeze drying 190
9.3.1.1 Mass and heat-transfer modelling 190
9.3.1.2 Primary drying modelling 191
9.3.1.3 Secondary drying modelling 192
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
10.2.1 Roller drying 205
10.2.2 Spray drying 206
10.2.3 Freeze drying 208
10.2.4 Spray freeze drying 208
10.3 Properties of dairy powders as influenced by drying method 208
10.4 Physical properties 209
10.4.1 Morphology, particle size, shape and distribution 209
10.4.2 Density 210
10.4.3 Reconstitution properties 213
10.4.4 Agglomeration and instantization 216
10.4.5 Flowability and stickiness 216
10.4.6 Heat and coffee stability 217
10.5 Chemical and sensory properties 218
10.5.1 Protein quality 218
10.5.2 Non-enzymatic browning 219
10.5.3 Oxidation and chemical quality 219
10.5.4 Sensory quality 220
10.6 Properties of special powders 220
10.6.1 Whey powders 220
10.6.2 Whey protein concentrates 221
10.6.3 Cheese powder 221
10.6.4 Yoghurt powder 222
10.6.5 Infant milk powders 222
10.6.6 Dairy whiteners 223
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
11.3.1 Metal cans 232
11.3.2 Glass bottles 232
11.3.3 Stretch-wrap packaging 232
11.3.4 Flexible pouches 232
11.3.5 Bag-in-box packages 233
11.3.6 Cups 233
11.3.7 Paper-board containers 233
11.4 Packaging of dried milk products 234
11.4.1 Packaging of whole milk powder 235
11.4.2 Packaging of non-fat dried milk powder 236
11.5 Developments in packaging techniques 237
11.5.1 Intelligent packaging 237
11.5.2 Active packaging 238
11.5.2.1 Migration mechanism in active packaging 239
11.5.2.2 The use of scavengers (absorbers) to prevent lipid oxidation 239
11.5.3 Nanotechnology in dairy packaging 240
11.5.3.1 Bionanocomposites and their applications 241
11.5.3.2 Modelling the barrier properties of polymer-clay nanocomposites 242
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
12.2.1 Multistage drying process 250
12.2.2 Some unique process layouts 251
12.3 Advances in operating spray dryers 252
12.3.1 Controlling the drying process 252
12.3.1.1 Single droplet to dryer-wide prediction 252
12.3.2 Controlling powder stickiness and deposition 259
12.4 Advances in operating fluidized-bed dryers 261
12.4.1 Controlling crystallization 261
12.4.2 Controlling agglomeration 262
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
13.4.1 Automation of industrial-scale spray dryers 273
13.4.2 Efficiency of spray-dryer operation 274
13.4.3 Bottlenecks in industrial spray-drying 276
13.4.4 Hygiene in spray-dryer operation 277
13.4.5 Safety aspects of spray drying 278
13.5 Industrial drum drying of dairy products 279
13.5.1 Critical control points in industrial drum drying 280
13.5.2 Energy efficiency of drum drying 282
13.5.3 Safe operation of drum dryers 283
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
14.2.1 Fouling 288
14.2.1.1 Mechanisms 288
14.2.1.2 Factors affecting fouling 289
14.2.2 Stickiness 291
14.2.3 Fires and explosions 292
14.2.4 Powder loss 293
14.2.5 Transport of powder 293
14.2.6 Storage of dairy powders 294
14.2.7 Plant economics 294
14.2.8 Development of speciality dairy powders 294
14.3 Use of modelling as a tool to solve some challenges 295
