Nutrient and antinutrient retention in indigenous white cassava gari and provitamin A biofortified yellow cassava gari fermented over different time periods

摘要

This study evaluated the interaction between changes in fermentation period and nutrient/antinutrient composition of indigenous white cassava (IWC) gari and provitamin A biofortified yellow cassava (pVABYC) gari. For both the cassava varieties, as the fermentation time was increased from 2 to 5 days, the moisture and fat contents increased significantly whereas the ash and fibre contents reduced significantly. Phytate level decrease by 15.8% and 10% in the IWC gari and pVABYC gari respectively due to increase in fermentation period from 2 to 5 days. Tannin reduced by 3.4% and 5.1% while cyanogenic potential decreased by 10% and 27.8% in the IWC gari and pVABYC gari respectively due to increase in fermentation period from 2 to 5 days. As the fermentation time increased from 2 to 5 days, the total carotenoids, β-carotene, and provitamin A carotenoids reduced by 20.7%, 22.2%, and 23.4%, respectively, for pVABYC and by 22.6%, 21.4%, and 20.7%, respectively, for IWC. The percentage retention of the total carotenoids, β-carotene, and provitamin A carotenoids in the gari samples obtained from the two cassava varieties decreased significantly with an increase in the fermentation time. In conclusion, as the fermentation time increases, pVABYC is found to have a better nutritional retention capacity than IWC. Thus, pVABYC gari retains more nutrient in addition to providing 100% more β-carotene than IWC.