SCREENING FOR CYANIDE DEGRADING CAPABILITY OF SOME MICROBIAL CASSAVA FERMENTERS
SCREENING FOR CYANIDE DEGRADING CAPABILITY OF SOME MICROBIAL CASSAVA FERMENTERS
No Thumbnail Available
Date
2014-06
Authors
ODA, ONOJA
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Cyanide is a chemical compound that occurs in biomolecules such as cassava as cyanogenic glycoside. Cassava and cassava products are therefore unsafe for consumption if not properly processed. A very efficient method of processing cassava is fermentation. Seven microbial cassava fermenters were isolated and characterized as Weissellaconfusa, Lactobacillus brevis1, Lactobacillusfermentum 1, Lactobacillusplantarum 1, Aspergillusniger, Fusariumsp and Trichodermasp. The lactic acid bacteria were isolated on deMann, Rogosa and Sharpe (MRS) agar while the moulds were isolated on malt extract agar (MEA). The bacteria were characterized with analytical profile index (API) 50 CH and API 50 CHL medium and the moulds were characterized using microscopy and fungal atlas. McFarland turbidity standards and haemocytometre were used for the determination of the inoculum size of bacteria and mould respectively. Result of cyanide screening showed that reduction of cyanogenic glycoside was significant on the third and fourth day of fermentation as indicated by the result of the analysis of variance (ANOVA), P<0.05, with Lactobacillus plantarum 1 as the organism with the highest cyanide degrading potential, with residual cyanide level of0.10±0.10d mgHCN/100 g cassava wet weight.Lactobacillus plantarum 1 having the most efficient cyanide degrading capabilitywas therefore used as starter culture for gari preparation.Another sample of gari was produced without the starter culture and sensory evaluation of the two gari samples was carried out by seven panelsof judges according to the Hedonic Scale, on five attributes namely appearance, aroma, taste, flavour and general acceptability. A t–test analysis was done to compare the two samples of gari and the result showed a significant difference (P< 0.05), with gari produced with starter culture as being more preferable. The result of screening for cyanide degrading capability which showed that all organisms isolated degrade cyanide in varying degrees is consistent with
Description
Keywords
CASSAVA FERMENTERS, CYANIDE DEGRADING