Umudike Journal of Engineering and Technology

The effect of drying methods on the retention of total carotenoids (TC) in pro-vitamin A HQCF was studied, two varieties of yellow-fleshed (UMUCASS 36 and UMUCASS 37) cassava roots were used for the study. The two varieties were prepared by washing, peeling, grating, dewatering, pulverizing, and processed into HQCF using different drying methods (Tray, oven, indirect active solar) while direct sun drying method was used as control. Results showed that while the fresh cassava roots of the two varieties had moisture content of 71% and 82% fresh weight (FW), their TC content was 8.23 μg/g and 8.15μg/g, respectively. Results indicated that the extent of carotenoids retention varied with the methods of drying, the highest retention was observed in tray drying (80% TC content retention) followed by indirect active solar drying (54% TC content retention) and oven drying (46%). The lowest retention was recorded in the sun drying method (20% TC content retention). The Higher Temperature-Short Time (HTST) combination rather than low temperature-longer time resulted in higher retention of TC. The highest TC retention was observed in oven dried sample at 120°C for 1 hour (55.1%) and the lowest TC retention was observed at 60°C for 3 hours (39.75%). Tray dried HQCF sample at 80-95°C for 1 hour showed a retention of 91.65% and 68.75% at 55-70°C for 2 hours.