This presentation summarizes pulsed electric field (PEF) technology. PEF involves applying high-voltage electric pulses between electrodes to food for less than one second. This minimizes energy loss from heating. PEF induces pores in cell membranes through electroporation, inactivating microbes without detrimental effects to food quality. A square pulse generator uses capacitors, inductors, and solid state switches to produce the high-voltage pulses. Processing factors like electric field strength, temperature, time of exposure, and pulse shape influence microbial inactivation during PEF. PEF improves the shelf life of foods like bread, milk, fruit juices, and more through more efficient microbial inactivation than conventional heat treatment.

1. Presentation on
Pulsed Electric Field(PEF)
Presented by Anurag Tripathi
13/IFT/011
Presented to Pushpendra Sir

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

3. Square pulse generator using a
pulse forming network
 3 Capacitors
 Inductors
 Solid State
Switching
devices

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–
50°C )
 Pressure. Pressure is applied to inhibit
the formation of air bubbles.

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.

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.

7. PEF technology in food
preservation
Improves shelf life
of:
 Bread
 Milk
 Fruit Juices
 Liquid Eggs
 Apple juice
 Brewers Yeasts

8. Efficiency over Heat
Exchanger

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.

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

12. THANK YOU