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. RESULTS 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). African Journal of Health Sciences Volume 34, Issue No.4, July- August 2021 476 CONCLUSION 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

Evaluación bacteriológica de la leche y queso de cabra distribuidos en el Area Metropolitana de San José, Costa Rica

En los últimos años, se ha dado en Costa Rica y a nivel mundial, una creciente producción, industrialización y consumo de la leche de cabra y sus derivados. No obstante, a nivel nacional no se ha realizado una caracterización de estos, por lo que el objetivo de este estudio es determinar las características microbiológicas de la leche y el queso fresco de cabra que se distribuyen en el área metropolitana de San José, Costa Rica, y así evaluar su potencial impacto en el plano económico y a nivel de Salud Pública. Se analizó un total de 25 muestras de leche cruda de cabra obtenidas por ordeño manual y provenientes de cinco productores diferentes, analizados en cinco fechas diferentes y 15 muestras de queso de cabra elaborado con leche pasteurizada, provenientes de tres productores costarricenses que distribuyen el queso comercialmente y también analizados en cinco oportunidades distintas. El estudio abarcó el análisis de microorganismos de deterioro (bacterias aerobiasmesófilas y bacterias lácticas), indicadores de higiene (coliformes totales), de contaminación fecal (coliformes fecales), de manipulación (Staphylococcus aureus) y patógenos (Listeria monocytogenes y Salmonella spp.). Los resultados para el recuento total aerobio mesófilo y de bacterias lácticas de las muestras de leche y queso resultaron elevados, indicando una disminución en la vida útil del producto. En cuanto a coliformes totales, el 100% las muestras de leche presentaron recuentos que superan los límites establecidos por la legislación para leche cruda de consumo humano costarricense y el 76% presentó coliformes fecales. Contrario a lo anterior, todas las muestras de queso, excepto una, fueron negativas para coliformes totales y fecales, lo cual sugiere que el queso es elaborado bajo buenas prácticas higiénicas. Los recuentos obtenidos para S. aureus fueron relativamente bajos y no se logró aislar Salmonella spp. ni Listeria monocytogenes a partir de las muestras de leche y queso analizadas.

Bacteriological evaluation of goat milk and cheese distributed in the Metropolitan Area of San José, Costa Rica. In the last years, there has been an increase in the production, industrialization and consumption of goat’s milk and derivate products, including cheese, worldwide. Nevertheless, in Costa Rica there is no study of these products, reason why the objective of this work was to determine the microbiological characteristics of goat’s milk and fresh cheese distributed in the Metropolitan Area of San José, Costa Rica, in order to evaluate its impact in the economical field and as a potential risk for Public Health. A total of 25 raw goat’s milk samples, obtained by manual milking from 5 different producers tested in five different dates and 15 cheese samples, elaborated with pasteurized milk, commercially available and coming from three different producers were analyzed. The study included the analysis of spoilage bacteria (total aeobic count and lactic bacteria count), indicators of hygiene (total coliforms), fecal contamination (fecal coliforms), manipulation (Staphylococcus aureus) and pathogens (Listeria monocytogenes and Salmonella spp). High results were obtained for the total aerobic count and lactic bacteria count of the milk and cheese samples, showing a reduced shelf life. Total coliforms, in limits beyond the established ones by the Costa Rican legislation for human consumption raw milk, were found in 100% of milk samples, as well as for fecal coliforms in 76% of them. All cheese samples, except one, were negative for these indicators, suggesting good manufacturing practices. S. aureus counts were low and both Salmonella spp. and L. monocytogenes were not isolated from samples analyzed.