Effects of rye pretreatment and enrichment with hemicellulolytic enzymes on ethanol fermentation efficiency
High temperature extrusion cooking of rye was compared to conventional pressure cooking and cold liquefaction with commercial hemicellulase addition to improve the efficiency of ethanol fermentation. The influence of saccharification with added hemicellulases on non-starchy carbohydrates of rye as well as on some quality factors of mashes and stillages were examined. Laboratory experiments showed the significant influence of the type of pretreatment and hemicellulases enrichment on the dynamic of saccharification and efficiency of ethanol fermentation. Using of hemicellulolytic enzymes along with saccharyfing enzymes during mashing increased the speed of breakdown of long chain carbohydrates and the yield of ethanol. In conclusion we can state that the increase of ethanol yield is not connected with pentosans fermentation but with the increased availability of hexose (starch) bound with pentose chain for amylolytic enzymes.
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