Effect of Physical and Chemical Treatments on Campylobacter Spiked into Food Samples

Abstract

Campylobacter spp. were isolated from rivers Mula, Mutha and Pavana by preT-Kapadnis Baseri and Preston enrichment-modified charcoal cefoperazone deoxycholate agar methods. Survival studies were conducted in fresh skim cow milk, chicken meat extract and mushroom extract at various temperatures. The sensitivity of Campylobacter strains inoculated in the food samples, to chemical preservatives, gamma radiation, microwave heating and water bath heating was studied. Campylobacter strains survived well in milk and chicken extract; however, temperature significantly affected their survival in those food samples. Although most of the chemical preservatives were effective against Campylobacter isolates, the sub-inhibitory values of acetic acid and lactic acid were relatively lower against these isolates. All the strains investigated for the effect of gamma radiation, were sensitive to doses less than 3 kGy. In case of heat preservation, around 9 min was required to eliminate Campylobacter spp. by heating in water bath at 50°C while approximately 13 s from food samples exposed to heating in a microwave oven. The effect of food preservation techniques on Campylobacter varied with the temperature and type of the food. Microwave treatment appeared to be much more effective than water bath heating and that chicken meat extract conferred an additional protection to Campylobacter as compared to milk or PBS.