Physico-chemical, sensory and microbiological qualities of yoghurt brands sold in Kano metropolis, Nigeria

Abstract

This study was conducted to evaluate the physico-chemical, sensory and microbiological qualities of some yoghurt brands sold in Kano Metropolis using standard procedures. The physico-chemical characteristics (viscosity, specific gravity, pH, titratable acidity, fat content) and Sensory properties (color, flavor, smell) were determined using the method of the Association of Official Analytical Chemists. The microbiological evaluations were based on the Aerobic mesophilc bacterial, Coliform, Escherichia coli, fungal counts as well as the detection of Staphylococcus aureus and Salmonella sp. using the method of Food and Agricultural Organization and the result presented. Two of the pathogenic strains S. aureus and Salmonella sp. were not isolated in any of the yoghurt samples analyzed. However, mesophilic bacteria, Coliform, Escherichia coli and fungi were positive in some samples. The results of chemical analysis showed no significant differences (p>0.05) between yoghurt samples. Organoleptically, sample YB5 was more significantly of better quality than the rest in terms of its color (7), its flavor (9) and had a significantly higher overall acceptability (p<0.05). The microbial load of all the yoghurt samples except for yoghurt samples (YB3, YB4, YB6 and YB7) microbiologically falls within the acceptable local and international standards.

Keywords: Microbiological, Yoghurt, Physico-Chemical, Sensory evaluation, Kano – Nigeria.