Microbiological analysis of pasteurized, microfiltered and uv treated milk samples

In the thermal method of milk pasteurization, milk is heated to 71.7°C for 15 seconds to destroy harmful bacteria and reduce the numbers of spoilage organisms to extend shelf-life and it doesn’t kill thermoduric bacteria. The non thermal processing milk such as microfiltration and UV radiation of milk are serving as an alternative methods for processing milk. The treatments were divided as pasteurized milk (TC - control), rawmilk (T1), microfilteredmilk (T2), UV treated milk at 1.5 kj and UV treated milk at 1.7 kj respectively. The milk samples were subject to microbiological analysis such as standard plate count method and coliform count during 0, 3, 6, 9, 12 and 14 days of storage at 4-5°C. Up to 14 days of storage at 4-5°C, the standard plate count of the milk samples TC, T2 and T3 exceed the limit of the legal limits prescribed by FSSAI, (2011). The UV treated milk sample 1.7 kj (T4) had no coliforms till 14 days of storage. The coliform count of milk samples viz., TC, T2 and T3 exceeded the limit on 6, 3 and 12 days as prescribed by Food Safety and Standard Authority of India. Hence, conclusion can be made that the UV treated samples obtained a low standard plate count and coliform count till 14 days of storage at 4-5°C.