Study on Saccharification Efficiency Improvement by Eurotium cristatum and Its Application in Kaoliang Spirit Production

Abstract

AbstractThe Kaoliang spirit is a classic Chinese baijiu. Glutinous sorghum is a unique raw material for its production; improving the saccharification efficiency of sorghum increases the liquor yield. Eurotium cristatum has been demonstrated to secrete amylase; however, it has not been used in saccharification. Therefore, this study aims to improve the saccharification efficiency with E. cristatum to enhance Kaoliang spirit production. The effect of E. cristatum on saccharification is evaluated by analyzing starch from glutinous sorghum. In addition, fermented sorghum microorganisms and liquor flavors are analyzed to establish the activity of E. cristatum. The results reveal that E. cristatum improves the saccharification efficiency, and 8% (m/m) of E. cristatum suspension is cofermented with 20% (m/m) of mold culture; the reducing sugar in the fermented sorghum reaches a maximum value of 40 g/100 g. During cofermentation with E. cristatum, the sorghum starch is enriched in amylose and has a lower molecular weight, clear crystal structure, and many holes. These phenomena express the effect of efficient saccharification by E. cristatum. Furthermore, E. cristatum also promotes other microorganisms while fermentation, therefore benefits the liquor flavors. This research provides the feasibility for saccharification improvement by E. cristatum, indicating its well scientific and significant commercial value.