Document Type : Research Paper

Abstract

Malting is a complex biotechnological process that includes steeping, germination and kilning of cereal grains under controlled temperature and humidity. This research investigated the effects of steeping (24, 36, 48 h) and germination time (3, 5, 7 days) on the quantitative and qualitative characteristics (hot water extract, malt extract color, soluble nitrogen, Kolbach index, total soluble solids, cold water extract) of malt extract obtained from barley (line EBYT88-17). Statistical analysis and process optimization were carried out using response surface methodology. Results showed that increasing steeping over a long germination period increased the the yield of hot water extract. Malt extract color increased as steeping and germination time increased and malt extract soluble nitrogen content varied from 0.081% to 0.46%. The results of process optimization showed that 47.99 h steeping and 6.89 day germination produced malt extract with the highest hot and cold water extracts and total soluble solids.

Keywords

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