Effect of malting conditions on the nutritional and anti-nutritional factors of sorghum grist

Abstract

Four grist samples, the same sorghum variety, from a modulated malting condition, were evaluated for nutritional and anti-nutritional factors. A raw grist sample of the same sorghum variety served as control. Results showed mineral elements increasing significantly (p≤0.05) with increasing steeping and germination periods as follows: Na+ (123%), K+ (29.55%), P2+ (4.71%), Ca2+ (157%) and Mg2+ (93.33%). Proximate composition of the samples in relation to the control showed that the total ash and carbohydrate levels decreased significantly (p≤0.05) by
34.4% and 24.33% respectively. The crude protein also decreased significantly (p≤0.05) by 28.5% and later increased by 0.10% relatively to the control. The moisture content and crude fibre steadily increased significantly (p≤0.05) by 37.13% and 72.5% respectively. A highly significant (p≤0.05) increase of 111.82% in the crude fat of the malted samples over the control was observed. Conversely,the oxalate, tannin, trypsin inhibitor activity (TIA) and phytate levels were significantly (p≤0.05) reduced by 34.13%, 8.45%, 36.5%, and 66%, respectively with increasing steeping and germination periods. The results suggest that malting, as a processing technique, can be used to effectively enhance the nutritional/organoleptic status of sorghum grist with concomitant reduction in some of its anti-nutritional factors.