Y. ISHIZUKA (1), T. Maruhashi (1), Y. Hida (1), K. Oka (1); (1) Suntory Liquors Limited, Osaka, Japan
Raw Materials II
Saturday, June 7 - 10:00 a.m.-11:45 a.m.
Level 4, State Ballroom
Nitrogen compounds in wort contribute not only to beer taste and foam quality but also affect the brewing process, provide the nitrogen source for yeast fermentation, and can affect beer filterability. Therefore, the control of protein modification during malting and mashing is very important in order to achieve target quality. At the 2010 MBAA Annual Conference, we reported that decoction beer had better fullness and bitter quality than infusion beer when relatively low protein-modified malt was used. At WBC 2012, we reported that the components of nitrogen compounds present in mash and wort also could be controlled by the decoction mashing procedure (mashing-in temperature, rest temperature, or rate of temperature increase) and that, based on these results, it had emerged that high molecular weight nitrogen compounds are a good indicator of bitter quality and foam cling. In this work, we investigated the influence of malt quality (protein content and degree of protein modification) on beer characteristics. We used some lots of European malt, total nitrogen, and Kolbach index, which are different from each other (the range of total nitrogen is 1.5–1.8%, and that of Kolbach index is 34–42%), and the decoction mashing procedure was adopted based on the result of our past studies. From the results of this work, we will discuss how total nitrogen and Kolbach index of malt influence fullness and bitter quality of beer.
Yusuke Ishizuka graduated with a master’s degree in environmental studies from the University of Tokyo in 2011. After joining Suntory Liquors Limited, he worked for 3 years in the Beer Development Department.