Abstract: The extended preservation of food has been a challenge for mankind throughout the ages due to presence of microbes in every considerable niche of human environment. The present work is based on Pulsed Electric Field treatment, where the liquid foods contaminated with microorganisms are subjected to application of Pulsed voltages in parallel plate static treatment chamber. This study examines the reduction in survival ratio after application of pulsed electric field on four organisms namely Bacillus cereus, Klebseilla pneumonia, Staphylococcus aureus and Pseudomonas aeruginosa when subjected to impulse wave of 1.2/50µs in parallel plate treatment chamber. The treatment voltage was varied in the range 20-80 kV and the number of treatment pulses varied in the range of 25 -100 pulses. The results showed that Staphylococcus aureus was the most sensitive organism with a 7-order reduction followed by Bacillus cereus and Klebseilla pneumonia with a 6-order reduction, when they were exposed to 80KV and 100 pulses. The most resistant organisms were Pseudomonas aeruginosa with only a 4-order reduction.

Keywords: Microbes, Inactivation, Non-Thermal, PEF.