Quality Test for Raw Milk

Abstract

Cow milk has long been considered a highly nutritious and valuable human’s food but: it is an excellent culture medium for many microorganisms, especially bacterial pathogens. There is a constant challenge in milk production to prevent or minimize the entry and subsequent growth of microorganisms in milk. Production of milk and milk products of superior quality and prolonged shelf life with the ability to provide a safe and wholesome food for the consumers is needful. This study is therefore aimed at evaluating the microbial quality of raw cow milk from different dairy farms. Bacterial pathogens were isolated from the milk samples and the isolates were characterized and identified to be Salmonella typhi, Shigella dysentriae, Escherichia coli, Enterobacter aerogenes, Bacillus cereus, Klebsiella pneumoniae, Pseudomonas cepacia, Aeromonas hydrophillia and Pseudomonas fluorescens. Pseudomonas fluorescens was the most predominant of the isolated bacteria. The total bacterial counts of the milk samples ranged from 0.2x10⁶ CFU/ml to 4.2x10⁶ CFU/ml. Also, the total enterobacteriaceae count ranged from 0.8x10⁶ CFU/ml to 2.6x10⁶ CFU/ml while the total salmonella-shigella count was found to range between 0.5x10⁶ CFU/ml and 1.1x10⁶ CFU/ml. Antibiotic susceptibility profiles of the isolates was determined; 10% resistance and 90% susceptibility to clinically relevant antibiotics was noted amongst the isolated bacteria pathogens. Resistance to more than two antibiotics was found in Salmonella typhi. The presence of these bacteria pathogens in the samples analytics considered to be an indicator of poor hygiene and sanitation during milking and post milking processes. It is therefore recommended that good sanitary measures should be taken by the people handling the cows and it must also be ensured that the cows are always in good health Condition.