Evaluation of Bacterial Load in Four Commercially Sold Yoghurts in Warri, Delta State, Nigeria

Abstract

The major ingredient in ice-cream a popular children favourite snack, commonly sold to them at their school gate during the dry season is yoghurt. Therefore this paper investigates the bacteria load in these yoghurt ice-creams are important as they determine the health of the consumers. The bacteria load of four commercially sold yoghurt samples in Warri, Delta State, Nigeria using standard methods. Results reveal the presence of Streptococcus thermophilus, Streptococcus salivarius and Lactobacillus bulgaricus spp. The highest number of colonies were observed in CS1[NA, 232 and PC, 218] and CS2 [NA, 282 and PC, 91] while lower number of colonies were observed in HO [NA, 120 and PC, 90] and for NY [NA, 118 and PC, 112]. It was observed that Colony Forming Units for Nutrient Agar (NA) were consistently higher in all four brands of yoghurt than Colony Forming Units for Plate Count Agar. An average of 157 colonies were observed on both nutrient Agar and Plate count Agar. Colonies observed was similar in both Plate Count Agar and Nutrient Agar in the 4 brands of yoghurt. All the isolates were highly susceptible to Norfloxacin and resistant to Gentamicin, Drovid and Clindamycin. The results of the microbial quality indicate that the yoghurt are of acceptable food quality, with probiotic potential.