Microbial modification of the texture of grated cassava during fermentation into akyeke.
The traditional akyeke inoculum and fermenting akyeke, an indigenous cassava product, were investigated to identify microbial species responsible for the modification of cassava texture during fermentation. Both field and laboratory samples were examined and only some cultures isolated on Plate Count Agar and Malt Extract Agar were found to be capable of causing a softening of cassava tissue when plated directly on sterile cassava slices. The cassava tissue softening isolates on PCA were tentatively identified as Bacillus subtilis and isolates on MEA as Candida tropicalis and Zygosacchromyces florentinus. The population of B. subtilis in the laboratory sample of inoculum was found to be 2.4 x 10(9) cfu g(-1) and increased during dough fermentation from 1.1 x 10(7) to 3.5 x 10(9) cfu g(-1) after 96 h. C. tropicalis was present in the inoclum at 3.0 x 10(9) cfu g(-1) and increased during dough fermentation from 3.2 x 10(6) to 6.9 x 10(7) cfu g(-1) whilst Z. florentinus was present in the inoclum at 9.1 x 10(8) cfu g(-1) and increased from 8.1 x 10(5) to 7.5 x 10(6) cfu g(-1) during dough fermentation.
Obilie
Eric Mantey
EM
Department of Nutrition and Food Science, University of Ghana, Legon, Ghana.
Tano-Debrah
Kwaku
K
Amoa-Awua
Wisdom Kofi
WK
D001412:Bacillus subtilis / Q000254:growth & development / Q000302:isolation & purification*; D041022:Candida tropicalis / Q000254:growth & development / Q000302:isolation & purification*; D015169:Colony Count, Microbial; D005285:Fermentation; D005516:Food Microbiology; D002365:Manihot / Q000382:microbiology*; D020068:Zygosaccharomyces / Q000254:growth & development / Q000302:isolation & purification*