Composition and hardness of malting red and white kaffir sorghum [Sorghum bicolor (L.) Moench] dried under the sun.

This investigation determined how changes in chemical composition of malting red and white kaffir sorghum grains dried under the sun affected the resistance of the malts to fracture as determined by the Monsanto Hardness Tester. The sorghum grains were malted by a modification of the 2-step wet steep method and dried under the sun. The results showed that malting increased diastatic activity to peak values of 78.40°L and 56°L in the red and white malts; moisture content from 115 to 165 g/kg and 125 to 170 g/kg, crude protein from 104.20 to 183 g/kg and 92.8 to 153.20 g/kg respectively but decreased the fat content. Grain hardness decreased from 83.20 to 42.50 N in the red malts and from 72.70 to 39.30 N in the white. The increases in diastatic activity, moisture, crude protein and reduced fat contents appear to have contributed most to the reduction in grain hardness.