NIGERIAN JOURNAL OF SCIENCE AND ENVIRONMENT
Journal of the Faculties of Science and Agriculture, Delta State University, Abraka, Nigeria
ISSN: 1119-9008
DOI: 10.5987/UJ-NJSE
Email: njse@universityjournals.org
STUDIES OF CYANIDE CONTENT AND MICROORGANISMS INVOLVED IN CASSAVA (MANIHOT ESCULENTA) FERMENTATION
DOI: 10.5987/UJ-NJSE.17.103.3 | Article Number: 75439C20 | Vol.10 (3) - December 2011
Author: Okoko F. J.
Keywords: Fermentation, Cassava, Microorganisms, Cyanine
Fresh cassava cortex, peels and leaves were studied for their cyanide content and microorganisms involved in their fermentation process. The total bacteria and fungi count, using the standard plate count, the cyanide content of each of the samples and their pH were evaluated. The results obtained showed that the species of Citrobacter feundii, Providentia, Acetobater and Lactobacillus were the bacteria isolated and identified during the fermentation while Aspergilius. Pencillium, Rhizopus, Candida and Geotrichum species were the fungi identified. The total viable bacteria count increased between 5.96 to 9.6, 6.23 to 9.9 and 5 to 9.85 (log 10cfu/ml) respectively for the cortex, peel and leaves while the total viable fungi count increased also between 6.23 to 9.56, 6.15 to 8.58 and 5.3 to 7.94 (log 10cfu/ml) respectively for the same samples throughout five days of fermentation. It was found that the cyanide content decrease with increase in the days of fermentation with the highest cyanide content of 120CN/g recorded in the peels and the lowest of 93.3CN/g in the cortex. The pH of the three samples also decreased with increase in the days of fermentation. It is apparent from the findings that microorganisms are involved in cassava fermentation and the cyanide content of cassava can be considerably reduced by the process of fermentation.
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