Quality evaluation of fermented cow milk ( Nunu) consumed in some metrpolises in Southern Nigeria
Date
2021-09
Authors
Journal Title
Journal ISSN
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Publisher
Federal University of Technology, Owerri
Abstract
The study was carried out to evaluate the quality of Nunu (fermented raw milk) taken at different sampling locations from Owerri, Obinze, Elele, Asaba and Enugu. The mean total bacterial count from these five locations were 9.55log10cfu/ml, 9.67log10cfu/ml, 9.58log10cfu/ml, 9.57log10cfu/ml, and 9.542log10cfu/ml respectively, which showed no significant difference (p>0.05) between the different locations. The mean values were significantly higher (p<0.05) than the recommended level of 6.03log10cfu/ml by East Africa Community Standards. The mean total Campylobacter count also showed no significant difference (p>0.05) between the different locations, with least mean value 3.49log10cfu/ml from Owerri and Enugu. The mean total Salmonella count also showed no significant difference (p>0.05) with mean least value of 1.28log10cfu/ml, and highest of 1.8695log10fu/ml, from Asaba and Enugu locations respectively. There was significant difference (p<0.05) in staphylococcal count (log10cfu/ml) between the different locations, with samples from Elele recorded the highest mean value. The mean total coliform count showed no significant difference (p>0.05) between the different locations, with means being above standard. The isolated bacteria included Staphylococcus sp, Salmonella spp, Bacillus spp, Klebsiella spp, Campylobacter spp, Enterobacter spp, Enterococcus spp, Escherichia coli, Micrococcus sp and Shigella spp. The biochemical test used to determine the milk quality such as Methylene blue and Resazurin test suggested high microbial contamination of the Nunu samples. Other biochemical tests such as alcohol test, Titrable acidity and Alkaline phosphatase activity were recorded high and was significantly (p<0.05) higher than the standard by Thai Agricultural Standard. The Temperature of the samples indicated good condition for bacterial growth as it ranged from 27.470C to 27.790C. The pH indicated an acidic condition (4.69 – 5.23) which must have been caused by lactic acid producing bacteria. This study revealed that Nunu samples analysed contained heavy metals such as cadmium, lead and zinc but within permissible level. The nutritional composition showed that the values for protein, fat, and carbohydrate were within permissible level. This study concluded that the quality of Nunu produced and marketed in these five cities in southern Nigeria was poor, and consumers may be at risk of contracting milk-borne infections from continuous consumption of Nunu from these locations as at the time of this study. It is recommended that public health officers and all stakeholders in the food and health industry should play their roles in order to ensure safe quality Nunu production.
Description
A Master's thesis on "fermented cow milk ( Nunu)"
Keywords
Quality, contamination, Nunu, heavy metals, proximate composition., microbiology
Citation
Ezenweani, E. C. (2021). Quality evaluation of fermented cow milk (NUNU) consumed in some metrpolises in Southern Nigeria. (Unpublished master thesis). Federal University of Technology , Owerri.