| The demand and the price of barley is constantly rising for the growing beer output in recent years.Finding out a beer adjunct that meet the requirements of the local development is imminent.Guangxi and Guangdong are the largest cassava planting provinces in China.As its high starch content,less fat protein and other impurities,cassava can be used as an adjunct.At present,the use of high rates of cassava as adjunct technology in domestic haven't reported,so the study of cassava in beer utilization can provide new application space.This paper is based on the screening of raw materials,pasting auxiliary materials process,and saccharification process to make research of high proportion excipients of wort.What's more,study of boiling and filter wort and tracking the process of fermentation is make.Combined with adding enzyme method for improvement of the excipients proportion,which explore the new use of cassava.The main results were as follows:(1)The composition of south China No.9 cassava were analyzed,and compared it with rice materials,the feasibility analysis of cassava as adjunct is determined.(2)By the response surface method,the optimum condition of cassava gelatinization process is obtained:The amount of high temperature resistance of alpha amylase is 182.38 U/g,water material ratio is 5.33:15 the initial temperature is 46.29?,Under this condition the optimum viscosity paste mash is 2.39 mPa·s,the optimum DE value was 46.67%.(3)to determine the optimal control temperature of each process stage in the process of saccharification:acid resting temperature of 37 °C,protein resting temperature is 50 °C,sugar resting temperature is 65 °C,final temperature is 75 °C.(4)the optimal conditions of the enzymatic saccharification process is get from the response surface method:he ratio of water is 3.62:1,the amount of medium temperature of alpha amylase is 63.25 U/g,the amount of beta amylase is 108.08 U/g,the addition amount of saccharifying enzyme is 50 U/g,the reducing sugar content in this condition prediction get 79.96 g/L,alpha amino nitrogen content is 137.32 mg/L.(5)The single factor experiment of wort filtration process was obtained.The most suitable factors were as follows:the ratio of malt was 20%,the malt fraction of wheat was 40 mesh,the amount of xylanase was 25 U/g,the amount of ?-glucan was added 30 U/g.The optimum filtration conditions were as follows:the degree of pulverization was over 38.99 mesh sieve,and the content of xylanase was 26.32 U/g.The optimum conditions were as follows:the ratio of maltase,xylanase addition and ?-glucanase were measured.?-glucanase was added at 31.67 U/g,and the filtration time was 5.97 min.A single factor test was performed on boiling to determine the best boiling condition:boiling time is 90 min,boiling intensity is 10%,hops addition amount is 0.15%.(6)the optimum fermentation conditions were determined:the initial fermentation temperature is 10?,strain inoculation amount is 5 ml/L.Observing fermentation experiment with 50%,50%,55%,65%,70%of the wort complementary,and study on the correlation between the content of each substance and the addition of cassava excipients in the fermentation process:alpha amino nitrogen and sugar appearance as cassava material proportion increased negatively correlated.pH,alcohol content,diacetyl and fermentation degree increase with accessories.Senior alcohol and organic acid content as the supplementary material is associated with an increased proportion.Sensory evaluation is qualified,55%of the ingredients than the beer taste and indicators slightly higher than other accessories,but the difference is not big.Considering the choice of adding the largest amount of cucumber accessories 65%. |
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