Bacteriological and physiochemical evaluation of locally produced tiger nut drink (kunu aya) sold in Owerri metropolis Imo state Nigeria

Abstract

The public heath implication of consumption of contaminated and unregulated hawked drinks has received great attention in recent times. This work investigated succession parameters of micro-organisms and physiochemical characteristics of tiger nut (Cyperus esculentus) drink hawked in Owerri metropolis over a 72 hour period. Samples of freshly produced drinks were purchased from seven major locations (Ekeonuwa, Control, Ikenegbu, Futo campus, Ihiagwa, Obinze and Naze junction) in Owerri metropolis. Microbial evaluation of the drink samples was carried out using spread plate method. Physiochemical analysis of tiger nut drinks were carried out using standard A.O.A.C methods. The results indicated the presence of Staphyloccus sp, Microccus sp, Enterobacter sp, Bacillus subtilis, Bacillus cereus, Salmonella sp, Escherichia coli and Corynebacterium sp. These contrasted from organisms isolated from laboratory prepared control. The mean total bacterial counts indicated tiger nut drink sold around Naze recorded the highest total heterotrophic bacterial count (109 CFU/ml), tiger nut drinks sold at FUTO campus, Obinze and Ihiagwa recorded the highest total fecal coliform count (104 CFU/ml) and total Salmonella-Shigella count (104 CFU/ml), while the laboratory prepared recorded the least heterotrophic bacterial count (103 CFU/ml), zero total fecal coliform count and total Salmonella-Shigella count recorded. The pH and titratable acidity over a 72 hour period indicated that all the drinks were acidic, where the street sold drinks recorded the highest acidity compared to the laboratory prepared drink. Very low microbial count observed for the laboratory prepared tiger nut drinks underscores the importance of Good Manufacturing Practices (GMP). It is recommended that regulatory government agencies for food and drink products should step up campaign for adoption/implementation of GMP by local vendors/producers.