Microbiological Analysis of Zobo Drink Preserved with Scent Leaves (Ocimum gratissimum)

Abstract

Aim: To determine the microbiological quality of zobo drink preserved with scent leaves. Methods: The zobo drink and scent leaves were prepared and evaluated using standard microbiological techniques. Results: Twenty three (23) bacteria species and fourteen (14) fungi species were identified from zobo drink preserved with scent leaves samples. This reveals the major bacterial species to be Enterobacter spp, Staphylococcus aureus, Bacillus spp, and Micrococcus spp. and fungi species to be Aspergillus niger, Rhizopus spp and Penicillium spp. The bacterial and fungal counts decreased as the days increased with day 1 having the highest bacterial and fungal counts at 1.41x105 (cfu/ml) and 3.1x104 (cfu/ml) respectively. The control samples were generally higher than the counts recorded on the bacterial and fungal counts. Zobo + scent leaves (ZSC) recorded the highest bacterial count at 1.41x105 (cfu/ml), while the least was recorded for (ZSA) at 1.01x106 (cfu/ml). Zobo + Scent (ZSC) recorded the highest fungal counts at 3.1x104 (cfu/ml), while the least was recorded for ZSA at 1.2x105 (cfu/ml). From this study, Bacillus spp and Staphylococcus aureus were the most frequently occurring bacterial isolates with a high percentage occurrence of 8(21.6%) and 6(16.2%), while Penicillium spp was the most frequently occurring fungal isolate. Conclusion: The association of these microorganisms with foods such as the commercial zobo drinks may be as a result of poor hygiene or poor sanitary condition. The microbial counts showed that among the zobo drink preserved with scent leaves samples, zobo + scent leaves (ZSC) is the most predisposed product to microbial population due to the high microbial counts recorded. Therefore, the result revealed that the samples of zobo drink were directly and indirectly contaminated with high levels of pathogenic bacteria, but can be reduced by the addition of scent leaves as a preservative.