Journal of Applied Biosciences (J. Appl. Biosci.) [ISSN 1997 - 5902]
Volume 33: 2070 - 2075. Published September 9, 2010.
Microbiological quality of sachet packed cocoa based beverage marketed in Ibadan, Nigeria
Felicia C. Adesina, Obasola E. Fagade, and Adeniyi A. Ogunjobi*
Department of Botany and Microbiology, University of Ibadan, Ibadan, Oyo State Nigeria
*Corresponding author email: aaogunjobi@hotmail.comABSTRACT
Objective: To assess the microbiological qualities of seven brands of sachet packaged cocoa based beverages in Ibadan city.
Methodology and results: Sachet packed cocoa beverages were purchase from three different market outlets in Ibadan. They were serially diluted and evaluated by pour plate technique on nutrient agar, mannitol salt agar, Maconkey agar and potato dextrose agar. Isolates obtained were identified by cultural, morphological and physiological characteristics. Those that were suspected to produce enterotoxin among the isolates were screened for enterotoxin production. Microbial load of the beverages samples were monitored for 5 days after opening. The sugar content of the samples was also determined and the osmo-tolerant ability of the isolates was established. Total bacterial count obtained from the samples ranged from 1.8x101l – 4.1 x 101 cfu/ml, the coliform count ranged from 2 – 5 cfu/gm while the yeast and mould count ranged from 3.1 x 101– 1.4 x 102 cfu/ml. Bacterial and mould counts progressively increased during the 5 days period of storing the leftover samples at room temperature. Twenty three strains of bacterial isolates were obtained, twelve of which were Bacillus sp., two strains each of Salmonella and Micrococcus. Staphylococcus sp and Escherichia coli were also identified. Fungal isolates obtained were Aspergillus flavus, Aspergillus niger and Rhizopus sp. Sugar content of the samples was between 78 - 103 mg/gram while the growth of bacterial isolates reduced at higher glucose concentration (8 & 10%). One of the Salmonella sp caused production of enterotoxin in suckling mice.
Conclusion and application of findings: Results from this study showed that the content of sachet packed cocoa beverages should be consumed at once or stored in clean air tight tin after opening to avoid contamination by potentially harmful microorganisms.
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