Effect of malting time, mashing temperature and added commercial enzymes on extract recovery from a Nigerian malted yellow sorghum variety

摘要

Preliminary microbiological studies carried out on sorghum grains showed that the major microorganisms found were mainly bacteria and that aflatoxin-producing fungi were not found. The effect of added commercial enzyme preparations and different infusion mashing temperatures on extract yield, from sorghum malted at 30 degrees C, was studied. The infusion mashing method (65 degrees C) developed for mashing well-modified barley malt produces poor extract yields with sorghum malt. The extract yield from the sorghum malt in this study was very low with infusion mashing at 65 degrees C, without the addition of commercial enzyme preparations. A higher extract yield was obtained from the sorghum malt, without the commercial enzyme addition, when using infusion mashing at 85 degrees C. Both infusion mashing temperatures (65 and 85 degrees C) showed an improved extract yield over the control malt when commercial enzyme preparations were used during mashing of the sorghum malt. The added enzyme preparations resulted in a higher extract yield from the germinated sorghum when infusion mashing was performed at 65 degrees C over mashing at 85 degrees C. The use of individual commercial enzymes (alpha-amylase, beta-glucanase, protease, xylanase, saccharifying enzyme and combinations of some hydrolytic enzyme) increased extract yields, when complemented with the enzymes that had developed in the sorghum malt. Copyright (C) 2016 The Institute of Brewing & Distilling