Program Book - Master Brewers Association of the Americas

P-130
Fermentation course prediction with weight analysis
PETR KOSIN (1), Jan Savel (1), Adam Broz (1)
(1) Budweiser Budvar N.C., Ceske Budejovice, Czech Republic
There are situations in which brewers would like to know how
compatible their yeasts are with their wort and the conditions
at which they would like to ferment. These can be R&D tasks
concerning yeast viability and vitality, wort composition (for
example mashing schedule or addition of fermentation enhancing
products like zinc), tasks concerning fermentation conditions
(temperature control, pitching and aeration rate) or, for example,
the need to see a fermentation curve at a fermentability test. For
these and many others purposes the weight analysis test designed
by Savel in 1993 can be used. The test is based simply on periodic
weighing of a vessel with fermenting wort and computer supported
calculations of alcohol content, real and apparent extract or
apparent degree of fermentation. The test was sensitive enough to
recognize wort enhanced with 0.2 mg×L –1 of zinc or low-aerated wort
from normal wort at fermentation temperatures of 10 and 20°C. The
mathematical base of weight analysis, which is discussed, can also
serve as a fermentation performance prediction test. This is based
on fast (high temperature) fermentation of pitched and aerated
wort sampled from a brewery wort line. Since the course of brewery
fermentation depends not only on yeast vitality, the great advance of
such a test compared to yeast vitality based fermentation prediction
tests is that weight analysis results depend on both yeasts condition
and wort composition. Weight analysis mathematics can also help
microbrewers and homebrewers to control their fermentations
without expensive analyzers and the need to sample from their
fermentation vessels.
Petr Kosin received an engineering (M.S. equivalent) degree in
brewing and malting at the Institute of Chemical Technology
Prague, Faculty of Food and Biochemical Technology, Department
of Fermentation Chemistry and Bioengineering, Prague, Czech
Republic, in 2006. He worked on his diploma thesis, “Application
of Modern Methods for Yeast Activity Control in Brewery,” at
Budweiser Budvar, N.C. in Ceske Budejovice. He has been working
in research and development at Budweiser Budvar, N.C. since his
graduation. He also has been studying for his Ph.D. degree at the
Institute of Chemical Technology, Prague, Czech Republic, since
2007. His dissertation deals with customer perception of beer quality
parameters.
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P-131
Withdrawn
P-132
Improving fermentor utilization by using natural hop
antifoams
RAY MARRIOTT (1), Paul Hughes (2), Lenka Nevesela (2)
(1) Botanix Ltd., Paddock Wood, United Kingdom; (2) International
Centre for Brewing and Distilling, Heriot-Watt University,
Edinburgh, Scotland
The composition of wort makes it susceptible to foaming during
fermentation. This is controlled either by mechanical means or
by the addition of an antifoam compound normally consisting of
a suspension of silicone compounds. Brewers are often reluctant
to use silicones, and a fraction from hops has been isolated which
can suppress foam formation. Brewing trials with this material
have shown that in addition to effective foam suppression, the
utilization of the isoalpha acids is significantly improved, and some
negative flavor characteristics, such as the formation of diketones,
is suppressed. Minor changes in the aroma and flavor composition
have also been identified and are presented in this work, together
with suggested mechanisms of their formation or suppression.
Ray Marriott received his first degree in biochemistry at Cambridge
and subsequently completed a Ph.D. degree in terpene chemistry
at the University of Bath. Ray joined Botanix Ltd in 1996, where
he is now R&D director. Ray has spent over 35 years in the food
and flavoring industry in the United Kingdom, mostly in technical
management. He is a biochemist and has been primarily concerned
with the extraction and processing of natural products and the
mechanism and enhancement of enzyme pathways responsible for
the generation of key active compounds, particularly those that
can be derived from U.K. crops. Ray is a member both of the IBD
and ASBC and regularly presents papers on the applications of
hop compounds, covering all aspects of their use from aroma to
antimicrobials. He is also visiting professor of chemistry at University
of York, UK.