Presenter: Yusuke Ishizuka, Suntory Liquors Limited, Osaka,
Japan
Coauthors: Taichi Maruhashi, Yoshinori Hida, and Kaneo Oka,
Suntory Liquors Limited, Osaka, Japan
Nitrogen compounds in mash 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, and we must
consider optimizing the mashing procedures depending on
malt quality, and vice versa. It has become popular to use malts
with relatively high protein modification because they are both
easy to use and economical. However, this may cause low
fullness or an unpleasant aftertaste if the mashing method is
not carefully considered. At the MBAA Annual Conference in
2010, 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 could also
be controlled by the decoction mashing procedure (mashingin
temperature, rest temperature, or rate of temperature
increase) and that, based on these results, it appears that high
molecular weight nitrogen compounds are a good indicator of
bitter quality and foam cling. As mentioned above, decoction
mashing procedure influences beer characteristics when
relatively low protein modified malt is used. Furthermore,
the mashing procedure used after decoction may also change
the degradation of nitrogen compounds and affect Maillard
reaction products at the mash and wort boiling stage. In this
study, we investigate the influences of mashing temperature,
before and after the addition of decoction mash to residual
mash, and discuss the effects of mashing procedure on beer
characteristics, focusing on nitrogen compounds and Maillard
reaction products that result from enzyme reactions during the
mashing process.
Yusuke Ishizuka graduated with a master’s degree in
environmental studies from the University of Tokyo in 2011.
After joining Suntory, he worked for two years in the Beer
Development Department of Suntory Liquors Limited.
