EFFECT OF GERMINATION TIME AND TEMPERATURE ON IFTU MALT BARLEY (Hordeum Vulgare L.) QUALITY AND STUDY OF SOME ENGINEERING PROPERTIES OF GRAINS AND MALT FLOUR

Abstract

This study was conducted on the effect of germination time and temperature on iftu barley malt quality and some engineering properties of grains and malt flour. The experiment was planned with two factors: germination time (3, 4 and 5 days) and germination temperatures (15, 18 and 21oC). Nine combinations of treatments were laid out and executed in full factorial design with three replications. All samples were steeped at room temperature for 37 hrs and dried for 24 hrs at 50oC. Samples subjected to treatments were evaluated for malt quality, functional properties and engineering properties of non-malted and malted iftu barley grain and its flour. Proximate compositions of iftu barley grains were also analyzed. The malt quality of iftu barley germinated for 5 days at 21oC had better results with relatively higher Malting weight loss, diastatic power, and lower wort viscosity. Statistically, the highest values of the functional properties of the iftu malt flour, which included dispersibility, water absorption capacity, and swelling power were 75.61% 2.99 g/g and 0.85% for the sample germinated for 5 days at 21oC respectively. In case of the engineering properties of non-malted iftu flour were 45.95 g, thousand kernel weight, 79.01 kg/hL hectoliter weight, 27.82o angle of repose, and 0.82 g/mL bulk density were significantly (P<0.05) different from values which ranged from 32.88 to 36.85 g, 64.63 to 70.99 kg/hL, 29.86 to 32.03o and 0.68 to 0.74 g/mL of the respective attributes of iftu malt flour. Regarding grain quality requirements iftu barley fulfilled the acceptable range of the Asela Malt factory standard and European Brewery Convention (EBC) standard. Sample germinated for 5 days at 21oC, satisfied most Assela malt quality standard, and this germination time and temperature can be used for iftu malting to meet the growing shortage of malt barley in the brewing industry.