PROCESSING OF RAW AFRICAN STAR APPLE KERNELS USING ABSORBENTS PRECEDED BY PHYSICAL METHODS FOR REPLACING MAIZE IN FEED

Abstract

In poultry diet, maize has the highest inclusion rate and causes an increase in the price of feed. Some alternative novel feed resources are available but their nutritional composition are yet to be ascertained for animal feeding. This study investigated the appropriate methods of detoxifying the secondary metabolites in the African Star apple kernels (ASAK) using different methods for use in poultry. The seeds of African star apple were obtained from the fruit and thoroughly washed to remove the foreign materials, immature or broken seeds. They were further dehulled using a hammer mill to obtain the kernels. The extracted raw kernels were initially pretreated in three different groups of soaking for 12 hours + boiling for 30 minutes, soaking for 24 hours + boiling for 1 hour and soaking for 48 hours + boiling for 2 hours. They were sundried and milled for phytochemical screening. The first group was selected for further processing as treatment 1 and the use of three different absorbents of activated charcoal, bentonite and polyethylene glycol by mixing thoroughly with the milled kernels and placed in tight sealed containers for seven days as treatment 2, 3 and 4 respectively in a complete randomized design of three replicates each for screening to determine the most effective absorbent for detoxifying the kernels. The result revealed that soaking and boiling was effective on the oxalate and glycoside levels in the ASAK meal. The use of absorbents led to a significant (P<0.05) decrease in the residual secondary metabolites.