T. Ma (1), L. ZHU (1), Y. Li (1), Q. Li (1); (1) Jiangnan University, Wuxi, China

Poster

Corn starch has become a common adjunct for beer brewing in Chinese breweries. However, with an increasing ratio of adjunct used, problems like poor wort filtration performance arise, which greatly decreases the production capacity of breweries. To solve this problem, the influencing factors blocking wort filtration were evaluated, such as the size of corn starch particles, residual undecomposed corn starch after liquefication, and special yellow floats formed during liquefication. The effects of different enzyme preparations, including beta-amylase, glucoamylase, beta-glucanase, protease, and lipase on filtration of both liquefied corn starch and wort were also evaluated. The results indicated that the special yellow floats did not severely block filtration, while the small particle size and uniform shape of corn starch and its undecomposed residue after liquefication should be the main factors of filtration blocking. Adding beta-amylase and glucoamylase preparations significantly increased the filtration rates of both liquefied corn starch and wort. The results of this study are useful for our insight into filtration problem caused by corn starch in beer brewing and other bioprocesses and provide a technological solution using enzyme preparations.

Linjiang Zhu received a B.S. degree in biotechnology from Zhengzhou School of Light Industry in Zhengzhou, Henan, China. He received an M.S. degree in fermentation engineering from Jiangnan University in Wuxi, Jiangsu, China. He received a Ph.D. degree in microbiology from the Institute of Microbiology, Chinese Academy of Sciences in Beijing. He worked as a teacher in the Lab of Brewing Science and Technology, School of Biotechnology, Jiangnan University, in 2012. His research interests include new technologies in beer brewing, beer spoilage bacteria, and enzyme preparations used in the food industry.