Pulsed electric fields technology for the food industry : fundamentals and applications

1. INTRODUCTION......Page 1
1.1. Historical Evolution and Chronological Developments in Pulsed Electric Field Processing......Page 2
1.2. Present Status of Pulsed Electric Field Technology and Applications......Page 5
2. FUNDAMENTAL ASPECTS OFPULSED ELECTRIC FIELD TREATMENT......Page 7
2.1.1. Power Supply......Page 8
2.1.2. Treatment Chamber......Page 9
2.2.1. Technological Factors......Page 12
2.2.2. Biological Factors......Page 14
2.2.3. Media Factors......Page 15
2.2.4. Inactivation Kinetics and Modeling......Page 16
3.1. Combination Studies......Page 17
3.2. Drawbacks/Limitations......Page 18
REFERENCES......Page 19
1. INTRODUCTION......Page 25
2.1. Specific Power Consumption......Page 26
2.2. Average Power......Page 28
2.3. Voltage Waveforms......Page 30
2.5. Conclusion......Page 31
3. PULSED POWER SYSTEMS......Page 32
3.2. PEF Treatment Chambers......Page 33
3.3. High-Power Sources......Page 34
3.3.1.1. Capacitive circuits......Page 35
3.3.1.3. Ringing circuits......Page 36
3.3.2.1. Circuits with pulse transformers......Page 38
3.3.2.2. Circuits with storage transformers......Page 39
3.3.2.3. Voltage multiplier I \0䴀䄀刀堀ⴀ最攀渀攀爀愀琀漀爀......Page 40
3.3.2.5. Current multiplier \0堀刀䄀䴀ⴀ最攀渀攀爀愀琀漀爀......Page 41
3.3.3.1. Pulse fanning lines......Page 43
3.3.3.2. Pulse forming networks......Page 45
3.3.4. Networks with Pulse Forming Switches......Page 48
3.3.5. Concluding Remarks......Page 49
3.4.1. High-Power Capacitors......Page 50
3.4.2.1. Trigatrons......Page 52
3.4.2.3. Thyratrons and pseudospark switches......Page 54
3.4.2.4. Thyristors, diodes, and IGCT switches......Page 57
3.5.1. Basic Considerations......Page 60
3.5.2. Typical Devices......Page 61
APPENDIX A: DIFFERENTIAL EQUATION SYSTEM OF INHOMOGENEOUS PULSE FORMING NETWORKS......Page 63
ACKNOWLEDGMENT......Page 68
REFERENCES......Page 69
1. INTRODUCTION......Page 71
2. ELECTROPORATION OF BIOMEMBRANES......Page 72
3.1. Electron Microscopy Examination......Page 75
3.3. Loss of Osmotic Response......Page 76
3.4.1. Effect of Process Parameters: Electric Field Strength, Treatment Time, and Specific Energy......Page 77
3.4.2. Effect of Type of Microorganism......Page 79
3.4.3. Effect of Product Characteristics......Page 82
3.5. Occurrence of Sublethal Injury......Page 84
4. CONCLUDING REMARKS......Page 88
REFERENCES......Page 89
1. INTRODUCTION......Page 93
2. CRITICAL FACTORS DETERMINING MICROBIAL INACTIVATION BY PULSED ELECTRIC FIELDS......Page 94
2.1.1. Electric Field Strength......Page 95
2.1.2. Pulse Shape......Page 96
2.1.3. Pulse Width......Page 97
2.1.6. Specific Energy......Page 98
2.2. Microbial Characteristics......Page 99
2.2.2. Cell Size and Shape......Page 100
2.3. Treatment Medium Characteristics......Page 101
2.3.2. pH......Page 102
2.3.4. Composition of the Treatment Medium......Page 104
3.1. Collecting Data for Modeling Microbial Inactivation by PEF......Page 106
3.1.2. PEF Treatment......Page 107
3.1.3. Treatment Medium......Page 108
3.2. Primary Models for Describing Microbial Inactivation by Pulsed Electric Fields......Page 109
3.3. Secondary Models for Describing Microbial Inactivation Pulsed Electric Fields......Page 113
4. COMBINATION TREATMENTS......Page 118
5. CONCLUSIONS......Page 119
REFERENCES......Page 120
2. EFFECT OF PEF ON ENZYME ACTIVITY......Page 126
3. EFFECT OF PEF ON FOOD CONSTITUENTS......Page 132
3.1. Proteins......Page 133
3.2. Fats and Emulsions......Page 134
3.3. Vitamins......Page 137
4. GENERATION OF NEW COMPOUNDS......Page 138
5.1. Milk......Page 139
5.2. Juices......Page 140
5.3. Egg Products......Page 142
5.4. Other Foods......Page 143
REFERENCES......Page 144
1. INTRODUCTION......Page 147
2.1. Disintegration Index and Characteristic Damage Time......Page 148
2.2. Selective Concentration of the Electric Fields on Membranes in Biological Materials......Page 149
2.3.1. Electroporation of Membrane......Page 150
2.3.2. Joule Overheating of the Membrane Surface......Page 151
2.3.4. Distinctness of the Cell Damage......Page 152
2.4.1. Electrical Conductivity of PEF-Treated Tissues......Page 153
2.4.2. Characteristic Damage Timeand Optimization Criteria......Page 155
2.4.3. PEF-Induced Secondary Effects in a Cellular Tissue......Page 157
3.1. Example of a Laboratory Device for the Combined Pressing and PEF Treatment......Page 159
3.2. Mechanism of Solid/Liquid Expression from Biological Tissue Treated by PEF......Page 160
3.3.1. Consolidation Behavior......Page 162
3.3.2.1. Sugar beets......Page 165
3.4. Effect of PEF on the Behavior of Constant Rate Expression from Food Plants......Page 166
3.5. Combination of PEF with a Moderate Heating......Page 170
3.6. Pilot Studies of SolidlLiquid Expression Combined with PEF......Page 173
4. EFFECT OF PEF-ENHANCING ON DIFFUSION OF WATER AND SOLUBLE SUBSTANCES FROM TISSUES......Page 176
4.1. Models for PEF Treatment Enhanced Diffusion......Page 177
4.2. Influence of PEF Protocol, Temperature, and Fragmentation of Particles on the Extraction Kinetics......Page 179
REFERENCES......Page 184
2. PERMEABILIZATION OF CELL MEMBRANES......Page 188
3.2.1. Juice Processing......Page 190
3.2.2. PEF Treatment of Microalgae, Seaweed, and Other Aquatic Species......Page 192
3.2.3. Plant Oil Extraction......Page 193
3.2.4. Meat and Fish Treatment......Page 194
3.2.6. Sugar Processing......Page 195
3.2.7. Energy Requirements for Tissue Disintegration......Page 196
3.3. Microbial Decontamination......Page 197
3.4. Wastewater Treatment......Page 200
4. COST ANALYSIS......Page 201
4.1. Fruit Mash Disintegration for Juice Winning......Page 202
4.2. Cost Estimation for Beverage Pasteurization......Page 203
5. PROBLEMS AND CHALLENGES......Page 205
6. RESEARCH NEEDS, CONCLUSIONS, AND OUTLOOK......Page 207
REFERENCES......Page 208
2. PEAK POWER REQUIREMENTS......Page 213
3. CONTINUOUS POWER REQUIREMENTS......Page 214
4. POWER SUPPLIES, SWITCHES, AND TREATMENT DEVICES......Page 215
4.2. Switches......Page 217
4.3.1. Electrical Impedance......Page 218
4.5. Measurement Under Pulsed Conditions......Page 219
4.6. Partial Discharges, Electrical Breakdown, and Arcing......Page 221
5.2. Electrode Degradation by DC Offset......Page 222
5.3. Metal Release Under Pulsed Conditions......Page 224
5.4. More Sources of AC Components......Page 225
6.1. Energy Input......Page 226
REFERENCES......Page 227