Bactericidal effect of microwave on isolated bacterial cells in milk, paneer and khoa

The effect of microwave exposure of different menstra inoculated with selected bacterial cultures was investigated. The minimum exposure period in MYG broth required to bring out destruction of Salmoneuasp., P.aeruginosa and S.aureus except Ecoli, on MYGA and B.subtilis was 30 sec with low log count of 0.36 to 0.66. In skim milk the time taken for complete destruction of bacterial cultures when exposed to microwave was 40 sec except Ecoli and B.subtilis. B.subtilis showed destruction at 50 sec exposure itself revealing the sensitivity of the culture to microwave. The bacterial cultures inoculated to whole milk at 3.56 to 7.26 and exposed to microwave showed complete destruction at 40 sec exposure except in case of Ecoli. The minimum exposure period required to bring out complete destruction of inoculated Ecoli, Salmoneua sp., and S.aureus except P.aeruginosa and B.subtilis in paneer at 3.54 to 7.08 log count was 50 sec when plated on to selective media while low count of 0.63 to 1.60 noticed on MYGA at the same exposure time. In khoa, the time taken for complete destruction of inoculated E.coli, Salmoneua and S.aureus with log count 6.48 to 6.90, when exposed to microwave was 40 sec on specific selective media but on MYGA the complete destruction noticed by these bacterial cultures was at 50 sec.