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We studied the change of α-amylase, β-amylase, pectinase and cellulase activity,including the characteristics of malt starch and low molecular sugars during malting in thisarticle. Optimized the conditions for barley soaking and germination, explored therelationship between the viscosity of malt starch and other parameters, analyzed thecomposition of some low molecular sugar and changes in malt.Optimized the conditions for barley soaking by L9（34） orthogonal. we chose Baudinbarley as material, studied the influence of soak temperature, the amount of alkali andimmersion method on the activity change of α-amylase, β-amylase, pectinase and cellulase.The results showed that: the best soaking conditions before germination of Baudin barley,soak temperature is18℃, the amount of alkali is0.1%, immersion method is4hoursimmersion and8hours unimmersion. Selected conditions for barley germination afterimmersion by single-factor test. We chose Baudin barley as material, studied the influence ofgermination time, germination temperatures and the concentration of gibberellin on theactivity change of α-amylase, β-amylase, pectinase and cellulase. The results showed that: thebest germinating conditions of Baudin barley, germination time is18℃, the concentration ofgibberellin is0.3mg/L, germination time is4day.Through the germination test of two barley varieties at different temperatures, studied thechanges in viscosity of malt starch, characterization and structure of malt starch granules, maltfragility including α-amylase activity with germination time. The results showed that: with thelonger germination time, the smaller viscosity of malt starch, the higher level of damagedstarch granules, the greater fragility of malt, α-amylase activity increased rapidly and thensteadily. Under the condition of germination at18℃, the dissolve degree of malt greater than14℃, barley ofBaudin is greater than Ganpi-4, the linear correlation between malt starchviscosity and malt fragility, breakage rate of starch granules was significant. there were asecond regression relationship between α-amylase activity and malt starch viscosity.By liquid chromatography test method, we chose Baudin barley as material, under the premise of the best soaking and germinating conditions, studied the change of some lowmolecular sugars with the germination time. The results showed that glucose, maltose, andsucrose reached their’s maximum at the same time when germination time for5days, slightlyhigher than the germination time for4days.This article will be the first attempt for using the characteristics of malt starch toanalysis the dissolve degree of malt in the process of barley germination, at the same time,explored the relationship between the viscosity of malt starch and other parameters, this studynot only provide thetheoretical basis and technology method for preparation high-quality maltand improve the quality of beer, but also provides research-based for judge and control thedissolved degree of malt.
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