Pulsed electric field(pef)

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Post on 14-Aug-2015




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<ol><li> 1. Presentation on Pulsed Electric Field(PEF) Presented by Anurag Tripathi 13/IFT/011 Presented to Pushpendra Sir </li><li> 2. PEF technology High intensity (PEF) involves the application of pulses of high voltage(typically 20-8-kV/cm) to food place between 2 electrodes PEF treatment is continued at ambient sub-ambient or slightly above ambient temperature for less than 1s Energy loss due to heating of foods is minimized For food quality attributes ,PEF technology is considered superior to traditional heat treatment of foods Avoids or greatly reduces the detrimental changes in sensory and physical properties of food </li><li> 3. Square pulse generator using a pulse forming network 3 Capacitors Inductors Solid State Switching devices </li><li> 4. Processing effects Electric Field Increase in microbial inactivation with increase in intensity of electric field Temperature- With constant electric field strength, inactivation increases with an increase in temperature (35 50C ) Pressure. Pressure is applied to inhibit the formation of air bubbles. </li><li> 5. Processing effects Time of Exposure- Treatment time is defined as the product of the number pulses and the pulse duration. An increase in any of these variables increases microbial inactivation. Pulse Wave Shape- may be applied in the form of exponential decaying, square-wave. </li><li> 6. Pulsed electric field technology involves the application of microsecond high voltage pulses in the order of 10 to 60 kV. The high voltage pulses applied induce pores in cell membranes, causing a loss of barrier function, leakage of intracellular content and loss of vitality. </li><li> 7. PEF technology in food preservation Improves shelf life of: Bread Milk Fruit Juices Liquid Eggs Apple juice Brewers Yeasts </li><li> 8. Efficiency over Heat Exchanger </li><li> 9. Microbial Inactivation During the PEF process, lysis of micro-organisms is caused by irreversible structural changes in the membranes, leading to pore formation and destruction of the semipermeable barrier of the membrane. </li><li> 10. Electroporation cell exposed to high voltage electric field pulses temporarily destabilizes the lipid bi- layer and proteins of cell membranes. Plasma membrane become permeable and causes cell death </li><li> 11. THANK YOU </li></ol>


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