Application Of Raw Qu And Cooked Material Qu In Chinese Rice Wine Production

Chinese rice wine fermentation is a procedure affected by many factors. Yeast is the main driving force of fermentation, and Qu saccharifies starch. There are some kinds of enzymes in Qu, mainly are liquefying amylase ,saccharifying enzyme, proteolytic enzyme . The power of these three enzymes can straightly affect the saccharification and fermentation. Qu can be devided into two kinds: raw Qu and cooked material Qu. Through measurement of the activity of three enzymes, a result is reached that three activities of cooked material Qu are all higher than those of raw Qu. The power of liquefication is six times , saccharification is ten percent and proteolysis is three times more than that of raw Qu.After saccharifying at 30℃and 65℃, the results show that the saccharified product of using cooked material Qu is more than that of using raw Qu. Saccharifying at 65℃is faster than at 30℃at the beginning. But the enzyme activity also loses fast due to high temperature ,and the final product generation speed is more slower. It indicates that lower temperature does good to activity of various enzymes in the mash.In traditional process fermentation, raw Qu leads to a bad start, low fermentation speed, and not a thorough end. Cooked material Qu just leads to the opposite. And the mixed Qu is lie in the middle of them. Using Qu mixed in certain ratio of raw and cooked material Qu, can produces rice wine similar to that is made of only by raw Qu. The best ratio of raw and cooked material Qu is 8 to 2. It paves a road for reforming traditional process.In clear liquid process fermentation, mixed Qu takes the advantage of both Qus when making convertde mash. And the major constituents is between that of raw and cooked material Qu, too. When it comes to ferment, the converted mash made by cooked material and mixed Qu give good starts and thorough ends, for their mashs contain better nutrient. But the quility of end product is another sequence. Rice wine made by raw Qu is good, and that by mixed Qu is even better. In this process the good ratio is raw Qu using 70g/L and cooked material Qu using 20g/L. This experiment provides a scientific base to the proper using of raw and cooked material Qus in clear liquid process and the development of new product.