ENUMERATION OF MESOPHILIC AEROBES, COLIFORMS, SULPHITE REDUCERS AND ANAEROBIC SPOREFORMERS IN RAW AND PASTEURIZED MILK

Chepuru, Venkata Siva

ENUMERATION OF MESOPHILIC AEROBES, COLIFORMS, SULPHITE REDUCERS AND ANAEROBIC SPOREFORMERS IN RAW AND PASTEURIZED MILK

Date

1991

Authors

Chepuru, Venkata Siva

Publisher

AAU, Anand

Abstract

An attenpt has been nade to study the changes in nicrobiological quality of raw milk at various stages of milk collectionfWith an intention to find out the sources for addition of various groups of microorganisms and the differences in microbiological quality of cow and buffalo milk, if any. Special emphasis was on the study of incidence of anaerobic sporeformers in milk at these stages of milk production, collection and handling. Pasteurized milk samples were also analysed for incidence of anaerobic sporeformers, along with other groups of microorganisms. Just after processing. With a view to pinpoint the major sources of contamination of raw milk with anaerobic sporeformers and other groups of microorganisms, samples of fore milk and middle milk, milk can rinses and dung were examined for the incidence of these groups. The correlation existing among various groups of microorganisms was also calculated to know the co-incidence of various groups studied. Samples of raw cow and buffalo milk were collected from randomly selected individual producers, collection centres, and a commercial dairy plant. Bulk milk being sent to the commercial dairy plant from chilling centres was also sampled. Samplers of pasteurized milk were collected from the Students' Training Dairy, S.N.C. College of Dairy Science. Anand, Gujarat, within 30 minutes of processing. Fore milk, the first five streams from each teat, and the middle milk samples were collected from aii university farm, Gujarat Agricultural University, Anand. Fresh dung samples were also collected from the buffalo farm and milk can rinses from collection centres and an university dairy farm supplying milk to the commercial dairy plant. Samples were tested for the incidence of anaerobic sporeformers using two methods namely Sulfite Reducing Clostridial Spore Count and Presumptive C. perfringena count using (Egg - Yolk free) Tryptose - Sulfite - Cycloserine Agar, Mesophilic Aerobes namely coliforms, acid producers, total microorganisms and mesophilic aerobic spores.