[Properties of white sorghum diastatic malt]

Diastatic malt enzymes have potential to hydrolize pregelatinized starches releasing soluble sugars, lowering viscosity of slurries and allowing the use of high nutrient densities for preparation of cereal-based creams, baby food and drinks. Determination of the extent in which sorghum malt is able to develop desirable functional properties such as viscoty, water solubility and nutritional quality is fundamental. In this work the characteristics of a white sorghum during germination and the resulting malt were evaluated. "Dorado" white sorghum was germinated at 28 degrees C and 95% RH during 6 days in complete darkness, dried at 55 degrees C and ground to produce diastatic malt flour. Physicochemical, chemical, diastatic and nutritional characteristics of malt and its ability to liquify precooked flour slurries were determined. Maximum diastatic activity occurred at 3-4 days germination. Dry matter loss increased during germination at a rate of 2.7 percent units per day. Longer germination resulted in increased dry matter loss and decreased diastatic activity. Water solubility index of sorghum increased linearly during the first 5 days of germination probably caused by the production of soluble sugars and free amino acids. In vitro protein digestibility, lysine content and C-PER increased during germination. Sorghum malt was able to liquify precooked rice, wheat, oats or millet pastes (20% solids) in 5 min mixing at 30 degrees C. Utilization of malts with maximum diastatic activity are useful to liquify precooked cereal pastes or drinks and to increase the total solid contents and nutrient density while keeping the liquid properties of the product.(ABSTRACT TRUNCATED AT 250 WORDS)