The Effects of Malting Conditions on the Diastatic Power of Three Malted Nigerian Sorghum Cultivars
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Abstract
The effects of malting conditions on the diastatic power of three malted sorghum cultivars (SK 5912, ICSV 400 and KSV 8) were investigated. The three Nigerian sorghum cultivars were steeped in 0.01M NaOH, 0.01M Ca(OH)2 and distilled water, respectively, under air-rest and continuous steeping regimes. SK 5912 steeped in Ca(OH)2 gave higher hot water and cold water extract values than when steeped in NaOH and distilled water. KSV 8 when steeped in distilled water gave peak values for cold water extract during air-rest and continuous steeping regimes. For hot water extract, KSV 8 had peak values when steeped in NaOH whereas SK 5912 gave the least values when steeped in distilled water. Cold water soluble-carbohydrate gave peak values for ICSV 400 when steeped in Ca(OH)2 and the least values were recorded in NaOH steeped grains. The diastatic power of the three sorghum cultivars improved with increase in germination time except for ICSV 400-steeped in Ca(OH)2 and KSV 8 steeped in distilled water which showed decrease in activity on the 4th day in continuous steeping regime. The results show that steeping in dilute alkali solutions gave higher values than distilled water while air-rested steeping regime gave better values than continuous steeping regime. The results from this study suggest that increase in germination time enhanced the diastatic power of the malted grain.
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