A Study of Bacteriological Quality of Street-Hawked Milk in Ilesha Metroplolis, Osun State, Nigeria
Milk, a nutrient-rich liquid food produced in the mammary glands of mammals, contains low bacterial counts when it leaves the udder, but it may get contaminated from the environment, exterior of udder, water, soil, milkers’ hands and utensils. Contamination can serve as a source of spread of certain harmful human bacterial diseases like tuberculosis, diphtheria, salmonellosis and food poisoning if consumed in raw form. This study, therefore, was designed to evaluate bacteriological quality of milk samples collected from various localities within Ilesha metropolis.
Materials and Methods:
Twenty (20) samples of fresh raw milk were collected in sterilized bottles from various nomadic milk hawkers in Ilesha. Methylene blue reductase test, standard plate count on standard plate count agar and isolation of possible pathogens using selective culture media was carried out on the samples.
Of the 20 samples of raw milk collected for bacteriological analysis, 3 samples were found to be of excellent quality, 5 were very good, 4 were good, 5 were fair and 3 were of poor quality. The actual standard plate count for excellent and very good quality ranged between 33-54 and 62 - 80 colony forming units (cfu). The organisms isolated and biochemically characterized from the raw milk samples were found contaminated with Escherichia coli (4 strains), Staphylococcus aureus (8 strains), Streptococcus pyogenes (5 strains), Streptococcus agalactiae (3 strains) and Enterobacter aerogenes (5 strains).
The results obtained from this study showed that the milk sold in raw form could be hazardous to human health if sold without adopting hygienic measures.
Keywords: Bacteriological Evaluation, Street-Hawked Milk, Ilesa Metropolis, Osun State.