ABSTRACT

Yogurts are ready to drink foods commonly taken for energy production and for health in Nigeria. Therefore this study was carried out to determine the microbial and microbiological assessment of commercially prepared yogurts sold in Umuhaia to evaluate their food safety. The commercially prepared yogurt products were purchased from vendors and transported for microbial and microbiological analyzed using standard laboratory methods. A total of 26 bacterial strains and 4 fungi were isolated from ten (10) samples of yoghurt for microbiological assessment of yoghurt. The isolate were identified by morphological characteristics, pigmentation on media, microscopy, biochemical and sugar fermentation methods. The details of these isolates and their percentage occurrence comprising Bacillus subtilis (5), Escherichia coli (4), Staphylococci aurues (2), Lactobacillus species (8), Klebsilla species (3), Aspergillus flavus (1), Mucor alternaria (1) and Saccharomyces cerevisiae (2) The Lactobacillus species bacterial has the highest number of bacteria isolates (26.67%) while the lowest isolates were recorded in aspergillus flavus and Mucor alternarian with (3.33%) respectively. There were significant decline in pH, temperature and titratable acid. This study has shown that most yogurts contain probiotics isolates including Lacto bacillus and Saccharomycess which are therefore beneficial for human consumption, therefore all effort should made to sustain the standard of yogurt.