An Assessment of the Bacteriological Quality of Different Brands of Yoghurt Sold in Keffi, Nasarawa State, Nigeria

Abstract

An investigation was carried out to determine the bacteriological quality of the different brands of yoghurt sold in Keffi, Nasarawa State, Nigeria. Seven brands of yoghurt were identified to be sold in Keffi metropolis within the period, and these were designated A, B, C, D, E, G and H respectively. Samples of these brands were obtained from ten (10) different locations and were analysed using standard microbiological methods in order to determine their respective bacteriogical quality. The results obtained showed that the pH of the different brands of yoghurtwere in the range of 3.18 – 2.35. Yoghurt A had the highest pH value, while yoghurt G had the lowest. The results of the bacterial enumeration showed the lowest counts of 0.0 x 10³ for yoghurt A, C and F, while yoghurts D, G, E and B had counts of 3.6 x 10³,2.5 x 10³, 2.3 x 10³ and 3.4 x 10³ respectively. Yoghurts A, C and F had 0.0 x 10³ coliform count of 3.6 x 10³. The counts of Staphylococcusaureuswas 0.0 x 10³ in four brands (A,C,F and G), while there were counts of 4.5 x 10³, 3.8 x 10³ and 3.4 x 10³ for brands B, D and E respectively. Similarly, the counts of E. coli were zero except for brands B and E which had 3.6 x 10³ and 4.4 x 10³, respectively. The counts for Streptococcus pyogenes were zero for all the brands except D and G which had counts of 4.8 x 10³ and 3.6 x 10³ , respectively. The results of this study demonstrate that four (B, D, E and G) out of the seven brands of yoghurts sold in Keffi are hygienically poor in terms of bacteriological quality because of the varying numbers of bacteria in them. Yoghurts A and F which had zero bacterial counts are the most hygienic yoghurts sold in Keffi.

Keywords:Yoghurt, bacteriological quality, Keffi, Nasarawa State