EFFECT OF SOME PROCESSING VARIABLES ON ANGLE OF REPOSE AND COEFFICIENT OF FRICTION OF DRIED FERMENTED CASSAVA GRANULES

Abstract

The angle of repose and coefficient of friction gain importance during food and handling, storage, processing and during process of designing these type of machines. Therefore, this study was conducted to investigate the effect of some processing variables; drying temperatures, dewatering pressure, size reduction and fermentation period on angle of repose and coefficient of friction of dried fermented cassava crumbles. A 2⁴ factorial experiment was designed to investigate the experiment of these variables on the coefficient of friction and angle of repose. Each variables was examined at two levels; drying temperature (50⁰c and 80⁰c), dewatering pressure (5mp_a and 10mp_a), size reduction (hammer mill and renting in water) and fermentation periods (3 days and 5 days) yielding 16 experimental samples. The data were statistically analyzed using yates algorithm. The results obtained showed that the coefficient of friction on wood is higher than the coefficient of friction on steel. A change in drying temperature from 50⁰c to 80⁰c increase coefficient of friction by 19% on wood, while hammer milling the fresh cassava root before fermentation increase the coefficient of friction on steel by 7.5%. all the two, three, and four interaction effect were pulled together to test the significance at 1% level on steel ,while only drying temperature was significant at 1% level on wood. However, it was found that a change in fermentation days from 3days to five days reduces the angle of repose by 10%.