Microbiological evaluation of sachet water and street-vended yoghurt and “Zobo” drinks sold in Nsukka metropolis

Abstract

Microbial, physical and chemical characteristics of six brands of sachet water and street-vended yoghurt (two) and "Zobo" drinks (three) sold in Nsukka metropolis were studied. Parameters such pH, total dissolved solids, copper, iron, alkalinity, appearance, taste, colour, aerobic mesophilic count, coliform counts were evaluated. Data obtained from the study showed that the yoghurt and "Zobo" drinks sold at the moment are bacteriologically safe. "Zobo" drink samples had total plate count of 9.9×10 1 CFU/ml to 1.48×10 2 CFU/ml, negative to coliform, Salmonella, and E. coli. Yoghurt samples had total plate count of 9.9×10 1 CFU/ml to 1.59×10 2 CFU/ml, negative to coliform, Salmonella and E. coli. Sachet water samples had pH of 7.25 to 7.50, total dissolved solids of 2.66ppm to 15.03ppm, hardness of 0.24ppm to 15.00ppm, iron, nitrate and nitrite were not detected. A total plate count of 1.41×10 2 to 3.19×10 2 , negative to Salmonella spp and some positive to Pseudomonas spp, coliform and E. coli. Thus the need for improved water treatment methods and storage before drinking and use for food drink processing.

Microbiological screening of street-vended groundnut cake, <i>Kulikuli</i> and natural spices for reducing microbial contamination in the food snack

“…The use of contaminated water in the manufacturing of processed food in resourcepoor areas such as the present sample location has been reported (Mbaeyi-Nwaoha et al, 2012;Ayoade et al, 2013;Ogunyemi et al, 2015), However, results from the present study show that regardless of the microbiologically safe processing of the groundnut product in the laboratory by the use of sterilized distilled water and maintenance of standard hygiene procedures, there is only a marginal reduction in the level of contamination by aflatoxin producing microorganisms when compared with the field samples. These results indicate that not all the contamination of the finished product is ascribable to unhygienic processing of kulikuli but a major portion of the contamination has already occurred during the pre and postharvest, pre-processing stages of the groundnut.…”

Seasonal Microbial Conditions of Locally Made Yoghurt (Shalom) Marketed in Some Regions of Cameroon

“…The presence of coliforms in these yoghurts could pose an adverse effect in consumers' health and suggests negligence on the part of the producers or the yoghurt vendors as well as quality controllers. According to the standard stipulated by the National Agency of Food and Drug Administration Control (NAFDAC), E. coli and coliforms generally must not be detectable in any 100 ml of yoghurt sample [ 45 ]. Other probabilities of contamination can be from contaminated water source and equipment used or due to contamination at storage and display/sale outlet [ 46 ].…”

Microbial contamination of packaged drinking water in Nigeria

“…Of the 45 articles that evaluated total coliforms contamination, six showed zero risk of contamination [49,57,59,74,77,78], three reported total coliforms contamination but did not quantify the number of positive samples or brands [39,69,76]; and the remaining 36 studies showed crude contamination prevalence ranging from 5.13 to 100%. Overall, five of the total coliforms articles reported counts of 1-10 MPN per 100 ml [41,47,65,67,81], 19 showed counts of 11-100 MPN per 100 ml [35,36,38,39,42,43,46,48,50,51,53,5 4,56,68,72,79,80,82,83], nine showed counts >100 MPN per 100 ml [34,52,55,58,[69][70][71]73,76] while the remainder did not quantify the bacteria counts.…”