EFFECTS OF FINAL WARM WATER STEEP AND AIR REST CYCLES ON MALT PROPERTIES OF 3 IMPROVED NIGERIAN SORGHUM CULTIVARS

The effects of final warm steeping at 40-degrees-C and air-rest cycles on malting loss and other malt quality parameters of three improved Nigerian sorghum cultivars were investigated. Grains were steeped for 48 h under four different steep regimes then germinated for 4 days at 30-degrees-C. The effect of final warm steeping on kernel growth, malting loss, diastatic power, alpha and beta-amylase and extracts of the malts was significantly affected by air-resting, cultivar and the pair-wise interactions of cultivar and steep regime. Generally, malting loss and kernel growth reduced significantly (p<0.001) when the steep cycle was a combination of air-resting and final warm water steep at 40-degrees-C. Diastatic power, alpha-amylase, beta-amylase and extract also improved significantly in both ICSV 400 and KSV 8 when these grains were malted by a steep regime which combined both air-rest cycles and final warm water steep. However steeping these grains under a final warm water steep without air-resting led to a decrease in extract recovery and enzyme activity. Conversely steeping SK 5912 by a combination of air-resting and final warm water steep generally, inhibited rather than enhanced extract and enzyme development.