Characterisation Of Microorganisms Associated With The Spoilage Of Bread

ABSTRACT

This study was aimed at isolating and identifying different microorganisms associated with the spoilage of bread and this was achieved by using the standard Spread Plate method and also by carrying out different biochemical tests which include; Coagulase test, Catalase test, Voges Proskauer test, Methyl red test, Indole test, Urease test, Hydrogen sulphide test etc. The total of 5 samples used in this study were purchased from different shops in local markets and was exposed to the environment for 7 days. The media used in this were MacConkey agar, Nutrient agar, Sabouraud dextrose agar, Mannitol salt agar. The bacteria and fungi isolated in this study include; Bacillus species, Lactobacillus plantarum, Leuconostoc mesantreroids, Penicillium species, Fusarium species, Aspergillus niger and Aspergillus flavus. The bacterial organisms were identified using colonial morphologies, Gram staining and Biochemical tests while the fungi organisms were identified using colonial morphologies and Staining with Lactophenol cotton blue. The mean counts of organisms identified ranged from 1.07×10`5 cfu/g to 1.96×10`5 cfu/g, the fifth bread sample has the highest mean count of 1.96×10`5 cfu/g while second bread sample had the least mean count of 1.07×10`5 cfu/g.