Effect of refrigeration on prevalence and enumeration of psychrotrophic bacteria in raw milk
نویسنده
چکیده
Fifty milk samples were assessed for prevalence and enumeration of coliform bacteria under refrigeration. Refrigeration exerted profound effect conferring diminished growth of Citrobacter, Enterobacter and Serratia, however, itfavoured Salmonella, E.coli and Klebsiella on other hand. Among them, Salmonella appeared with highest load both in pre-refrigerated (23%) as well as post-refrigerated (46.3%) samples. A blend of responses toward erythromycin and polymyxin B was observed by various coliform isolates, however,polymyxin B was found more effective comparatively. Predominantly, these isolates exhibited Gamma (γ) hemolysis, while only Serratia and Klebsiella arose as possible pathogenic being β-hemolytic.
منابع مشابه
Psychrotrophic bacteria and milk and dairy products quality
The characteristics of microbial populations in raw milk at the time of processing has a significant influence on shelf life, organoleptic quality, spoilage and yields of the raw milk, processed milk as well as on the other dairy products. Unfortunately, cold and extended storage of raw milk, as a common practice in dairy sector today, favour the growth of psychrotrophic bacteria. Therefore, th...
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