Research Of Cross-flow Membrane Filtration Technology In Beer Brewing Industry

It is mature beer after fermentation.Although,most of the yeast and protein have been precipitated,there are still a few amount of substances suspended in the beer,which must be filtered before entering the packaging process.Cross-flow membrane filtration technology is a new technology,which does not need to be physically separated by filter media.It is to isolate bacteria or particles as "relative impurities" from the liquid to be filtered,so as to obtain the desired products.Under this background,the application of cross-flow membrane filtration technology in beer production was researched.The related contents are as follows: Firstly,the current status and development of beer filtration technology are elaborated,the principles and advantages of cross-flow membrane filtration technology are introduced,and the research background and significance are clarified.Secondly,research methods and materials were confirmed based on the production of craft beer,and experimental plans were designed.Then,specific experimental studies will be conducted to analyze the methods and effects of using cross-flow membrane filtration technology.Three experiments were conducted,namely the experiment on the factors affecting the flux of cross-flow membrane filtration in beer production,the experiment on the comparison of cross-flow membrane filtration technology and kieselguhrr filtration effect,and the experiment on cross-flow membrane cleaning.Through experimental research,it is found that:(1)Through the analysis of factors affecting the flow rate of cross-flow membrane filtration in beer production,it was found that the process parameters for the maximum flux were: membrane pressure difference of 0.18 MPa,tangential flow rate of 6m/s on the membrane surface,back washing interval of 5 minutes,temperature of the filtrate at-0.5 ℃,and continuous cross flow filtration time within 2.5 hours.By using the orthogonal experimental method to further analyze the impact of these five factors on flux,it can be concluded that the most influential factor is the membrane pressure difference,followed by the tangential flow velocity on the membrane surface.(2)By comparing the effects of cross-flow membrane filtration technology and kieselguhr filtration technology in beer filtration,it was found that the stability of the flow time curve of cross-flow membrane filtration technology is better than that of kieselguhr technology.The color,total acid,and microbial indicators of cross-flow membrane filtration technology are better than those of kieselguhr technology.The results of the two filtering methods showed significant differences in flavor indicators,with significant differences in aroma intensity values in sensory scores,while the other five indicators showed small differences(p>0.05).Overall,the effect of cross flow membrane filtration technology is better.(3)When analyzing the differences in cleaning effects of cross-flow filtration membranes in beer production,oxidants,alkaline,and composite enzyme cleaning agents were selected respectively.The results show that the oxidant can dissolve the attached substances inside the membrane while exacerbating membrane leakage,and it is not recommended to use it.The cleaning effect is best when the concentration of alkaline is 1.5%.The cleaning effect is acceptable when the concentration of composite enzyme cleaning agent is 0.1%,but excessive concentration can damage the membrane.