Significance of yeasts and moulds occurring in maize dough fermentation for 'kenkey' production.

Yeasts and moulds associated with the fermentation of maize dough during the processing of the West African traditional food 'kenkey' were investigated. A mixed flora comprising Candida, Saccharomyces, Trichosporon, Kluyveromyces and Debaryomyces species were isolated from raw maize, during steeping and early phases of fermentation. After 24-48 h of fermentation, Candida krusei and Saccharomyces cerevisiae dominated reaching counts exceeding 10(6) cfu/g. This succession of yeast populations and the significant multiplication of C. krusei and S. cerevisiae were observed in all cases for both the fermentation and the production sites investigated. Penicillium, Aspergillus and Fusarium species, including potential mycotoxin producers, were isolated from raw maize. Initial high counts of 10(5) cfu/g for moulds were reduced to less than 10(2)cfu/g within 24 h of fermentation. High levels of aflatoxins were observed in raw maize, and they were not affected during the fermentations.