Technical Session 11: Brewhouse Operations Session
Taichi Maruhashi, Suntory Liquors Limited, Osaka, Japan
Co-author(s): Tetsuya Arita, Yutaka Yamaguchi, Yoshinori Hida, and Kaneo Oka, Suntory Liquors Limited, Osaka, Japan
ABSTRACT: The nitrogen compounds in mash contribute not
only to beer taste, but also to the brewing process, nitrogen source for
yeast, and beer filterability. For this reason, control of protein
modification in malting and mashing is very important, and we must
consider optimizing mashing procedures depending on malt quality and
vice versa. Because it is both easy and economical, it has become
popular to use malts with relatively high protein modification. However,
this may cause low fullness or an unpleasant aftertaste if the mashing
method is not carefully considered. I reported at MBAA in 2010 that
relatively low protein-modified malt and low mashing-in temperature led
to better fullness and a bitter quality. Decoction beer has better
fullness and bitter quality than infusion beer when relatively low
protein-modified malt and a high mashing-in temperature were used. In
order to improve the quality of decoction beer further, the influence of
the mashing-in temperature and the heating process in the kettle mash
was investigated using laboratory scale mashing apparatus (50 g of
malt). Because it is also known that the protease activity of
low-modified malt is improved by a low mashing-in temperature of 35°C,
we first investigated the effect of mashing-in temperature in the kettle
mash on extraction and degradation of nitrogen compounds. A low
mashing-in temperature of 35°C produced more nitrogen compounds in the
mash than a temperature of 45°C. The appropriate heating rate and rest
temperature of the kettle mash produced larger quantities of nitrogen
compounds than were produced without a rest process in the same length
of time. We have described the suitable single decoction mashing
procedure for better extraction and degradation of nitrogen compounds as
determined by laboratory scale mashing experiments, and its influence
on beer quality was evaluated on a 100-L pilot brew scale.
Taichi
Maruhashi graduated with an M.S. degree from the Tokyo University of
Science in 2001. After joining Suntory, he worked for six years in the
position of second brewmaster at the Suntory Tonegawa brewery in Gumma,
Japan. He then went to Technische Universität München, Weihenstephan, in
Germany as an international student and studied there for three years.
He currently works in beer development.
VIEW PRESENTATION 37
