H. FUJIWARA (1); (1) Kirin Company, Limited, Yokohama, Japan
Yeast, Fermentation, and Microbiology
Thursday, June 5 - 10:00 a.m.-11:45 a.m.
Level 4, Red Lacquer Ballroom
The brewing yeast is cultured in several scaling-up steps, from a test tube to large culture vessels, using wort at each step. Usually the whole culture process requires a lot of time and effort. Moreover, it needs wort at each scaling-up step, so the yeast culture schedule is fundamentally restricted by the timing of wort production. This study attempts to solve these two problems. Our recent studies have revealed that the brewing of yeast culture in high concentrations using zinc-rich wort can reduce the number of scaling-up steps, while giving yeast a good fermentation performance in producing high quality beer. However, to make drastic improvements, it is necessary to make the yeast culture process more efficient in order to substantially reduce the number of steps in it and to eliminate the need to use wort. Considering this situation, we focused on fed-batch culture technology, which is usually used for baker’s yeast and researched how to culture brewing yeast using the fed-batch culture method. In baker’s yeast culture, feeding molasses to maintain a low sugar concentration enables a significantly higher concentration of yeast to be cultivated without ethanol being accumulated due to fermentation. When examining this method for brewing yeast culture using molasses, we found that a yeast cell concentration can be produced that is approximately 10 times or more greater compared with conventional methods.
Hiroki Fujiwara graduated from Kyoto University in 2012 with a master’s degree in agricultural chemistry and joined Kirin Brewery Company, Limited in the same year. He has worked in the Research Laboratories for Brewing Technologies and been engaged in the research and development of yeast and fermentation technology.