Environment and Hybrid Influences on Rapid-Visco-Analysis Flour Properties of Food-Grade Grain Sorghum
Grain processors would benefi t from informa- tion about the production environment and the infl uences of the sorghum (Sorghum bicolor (L.) Moench) hybrid on food-grade fl our proper- ties. The objective of this study was to deter- mine the effects of environment and hybrid on rapid-visco-analysis (RVA) fl our properties of commercially available food-grade sorghum. A randomized complete block experiment was planted in 12 environments, which included the 2004 and 2005 growing seasons and irrigated and dryland water regimes in eastern, central, and west central Nebraska, and a dryland, low-N environment in eastern Nebraska. The environment accounted for 71-85% of the total variation in RVA parameters, while the hybrid accounted for 11-23% and the environment- by-hybrid interaction, 1-3%. Unfortunately, the results of this experiment suggest that it is dif- fi cult to predict the effect that environment will have on resulting sorghum-fl our parameters. Although of secondary importance in terms of total variation in sorghum-fl our RVA properties, the choice of hybrid predictably and signifi - cantly contributes to sorghum-starch viscosity properties. Food-grade hybrids were grouped based on viscosity properties into those best suited for dry-mill and alkaline-cooked prod- ucts (Asgrow Orbit; Sorghum Partners NK1486) and those best suited for porridge, consumable alcohol, and ethanol production (Kelly Green Seeds KG6902; NC+ Hybrids 7W92; Asgrow Eclipse; and Fontanelle W-1000). These results were consistent with those previously reported for grain density.
A reassessment of sorghum for lager-beer brewing
Abstract The out-of-steep moisture of sorghum is lower than expected (33–36%), but is adequate for enzymic modification of endosperm substrates of sorghum, producing sufficient amylolytic enzymes for brewing lager-type beers. The 65°C standard mashing procedure limited extract recovery from sorghum malt due to inadequate gelatinization of sorghum starch. The 65°C mashing was, however, optimal for nitrogen solubilization and hydrolysis of the soluble proteins, yielding high levels of peptides and amino acids. In order to obtain optimal extract yield containing sufficient mashtun sugar/protein extracts from sorghum malt, a controlled temperature mashing regime would be required. A high germination temperature of 30°C is required for optimal sorghum malt qualities, even though excessively high respiratory and carbohydrate malting loss occurred at 30°C germination. This notwithstanding, sorghum germinated at 30°C contained higher nitrogen materials in the embryo than in the roots. Also the presence of minerals in the embryo of sorghum may, in part, influence the enzyme-producing potentials of the embryo of sorghum.
Development of amylolytic activities in sorghum and barley malt
A Nigeria-grown sorghum cultivar was observed to develop more Diastatic Power (DP) and β-amylolytic activity than a previously studied sorghum cultivar grown in Australia. Barley malt produced more Diastatic Power and β-amylolytic activity than the Nigeria-grown sorghum cultivar. In general, the kilned barley malt retained less α-amylolytic activity than kilned sorghum malt. The different diastatic potential of sorghum cultivars may reflect differences in genetic character or growth conditions.