Abstract

The study was conducted to track Bacillus species in the production - supply chain of fluid milk. A total of 20 milk samples were collected viz., raw milk samples, pasteurized milk immediately after pasteurization and pasteurized samples stored under refrigeration for two days from a private dairy farm and its milk processing unit, in Thrissur district. The samples were evaluated for microbiological quality parameters like Total Viable Count (TVC) and Bacillus count. The TVC observed in both raw and pasteurized milk samples were higher when compared to the prescribed standards by FSSA (2006). Raw milk samples and stored pasteurized milk samples showed presence of Bacillus organisms. But they were totally absent in pasteurized milk samples. Isolates showing peacock blue colored colonies surrounded by a yellow zone of   lysis in Bacillus cereus agar (BCA) were identified as Bacillus cereus organisms. The enteropathogenic effect of the isolates was studied by polymerase chain reaction (PCR) but none of the isolates from the milk samples were found to be pathogenic strains of B. cereus. The occurrence of Bacillus spp. and higher TVC in the milk samples, suggests that the protective measures are inadequate and good hygienic practices (GHP) to be followed especially at the farm level, and during post pasteurization .

Keywords : Milk, TVC, Bacillus spp.