Optimization Of Liquid Fermentation Process And Study On Physicochemical Properties Of Maotai-flavor Liquor Produced By Mixed Koji

Maotai-flavor liquor is an important distilled liquor among Chinese liquors,with a unique body style.The liquid fermentation method is used to produce Maotai wine,which provides new liquor technology for the rapid development of the Maotai wine industry.In this study,sorghum,glutinous rice,and soybean meal were selected as fermentation raw materials,and high-temperature Daqu,bran koji,and red koji were added for saccharification first,and then Saccharomyces cerevisiae was added for liquid fermentation.Blend the finished wine for tasting.In order to explore the ratio of various substances,single factor and orthogonal experiments were used to measure the alcohol content,total acid and total ester of Maoxiang wine as indicators,and the best production and processing technology was obtained.The content of Maotai-flavor liquor are quantitative and GC-MS qualitative analysis.The main conclusions of the study are as follows:(1)Selecting bran as the raw material for making bran koji,respectively explored the influence of different culture time and different moisture content on the process of bran koji,and finally determined the optimal culture time and water content for the growth and metabolism of bacteria in the preparation process of bran koji.The best preparation process condition for the quality of bran koji is in the bran with 50% water added,and the cultivation time is 75 h.The glucoamylase activity of the obtained bran koji was the highest.(2)Through single factor experiment and orthogonal experiment,the effects of raw material ratio,mixed koji ratio,added koji amount,material-water ratio on the alcohol content,total acid,total ester and sensory after fermentation were studied.Summarize the effect of the mean and variance analysis of each factor on the alcohol content,total acid,total ester and sensory results,obtain four sets of optimal fermentation process conditions,and verify the four sets of combine factors.And the results obtain the optimal fermentation process conditions as raw material,the ratio of sorghum:glutinous rice: soybean meal is 60?27?13,the ratio of high-temperature Daqu?bran?red yeast mixture is 1?3?2,the amount of koji add is 25%,and the ratio of material to water is 1?2.5.(3)Analyzed the physical and chemical indicators of the homemade Maotai-flavored wine,and finally measured the alcohol content of the Maotai-flavored base wine was 53%vol,the total acid content was 1.428g/L,the total ester content was 1.613g/L,and the solid content It is 0.09g/L,the methanol content is 0.03g/L,and the furfural content is 162mg/L.Using gas chromatography-mass spectrometry technology to qualitatively analyze the flavor substances of homemade liquid fermented Maotai-flavor base wine and solid-state fermentedMaotai-flavor base wine.The homemade liquid fermented Maotai-flavor base wine detected32 flavor substances,including 18 esters.Substances,accounting for 63.04% of the total aroma components;3 aldehydes,accounting for 3.74%;2 acids,accounting for 0.65%,etc.The main aroma components contained are ethyl butyrate,ethyl acetate,ethyl n-hexanoate,Ethyl caprylate,ethyl caprate,etc.The solid-state fermented soy-flavored liquor detected 23 flavors,of which 12 esters,accounting for 61.28%;3 aldehydes,accounting for 2.12%,etc.The main flavor components contained are ethyl acetate,ethyl butyrate,Ethyl n-hexanoate and so on.In summary,the use of high-temperature Daqu,bran koji,and red koji mixture to produce Maotai-flavored liquor by liquid fermentation method not only increases the rich sauce,but also shortens the period of Maotai-flavor wine brewing,increases the output value,and reduces Capital investment cost,provide new liquor technology for the rapid development of Maotai wine industry.