Abstract

Frank Chukwunwike Ogbo

The need to shorten the time taken for cassava tuber to ret has arisen because of increased demand for processed cassava products occasioned by population growth in developing countries. Locally developed technologies aimed at this objective which involved the addition of chemical substances to steep water were assessed to determine their efficacy. Retting time measured in hours was determined during 25 retting trials using separately in each set, a control and 0.5 ml kerosene/L, 1 g trona/L and 10 g nails/L of steep water. The results reveal that addition of chemicals to various extents influenced growth of microbes and production of organic acids during cassava retting. Trona inhibited detoxification of cyanogenic glycosides while kerosene and nails did not. Statistical analysis of retting time data showed that nails were efficacious in shortening retting time but that kerosene and trona were not. The mechanism of action of nails probably involved enhancement of growth and enzyme activity of microbes involved in production of macerating enzymes responsible for softening of tubers during retting. A better understanding of this process will be useful in developing safer and efficacious chemicals for shortening the retting time of cassava.