Finishing and Stability Session
Alexander Scheidel, Technische Universität München Weihenstephan
Co-author(s): Jens Voigt, Technische Universität München Weihenstephan, Germany
ABSTRACT: The clarity of a beer is the first impression of
the consumer and one of the most important quality aspects of beer. The
filtration process after a conditioning maturation is needed to reduce
haze causing materials (e.g., polyphenols, proteins, yeasts, and
carbohydrates) to increase this quality aspect before filling and sale.
Conventional kieselguhr filtration with PVPP stabilization
(polyvinylpolypyrrolidone) is mainly used as a precoat filtration in
breweries to ensure stable beer quality. But, the use of diatomaceous
earth (kieselguhr) as a filter aid bears a few problems. It is expensive
to dispose of and furthermore the inhalation of SiO2 dust
may be carcenogenic. A few approaches were made to substitute kieselguhr
filtration. One of them is filtration with regenerable filter aids;
another common method is the selection of membrane filters without
filter aids. The chemical company BASF has developed a regenerable
filter aid called Crosspure. This filter aid has comparable
characteristics to diatomaceous earth. It is a combined filtration and
stabilization tool, is available in two grades of fineness, and can
replace kieselguhr in existing plants. Due to the availability of
different grades, it allows the brewery to adjust this ratio to achieve
an excellent filtration process and final beer quality. The possible
separation of the mixture has been investigated successfully, and in a
further step the filter cake resistance of the separated filter aid was
determined. With knowledge of the filter characteristics of separated
Crosspure, breweries are able to adjust an optimal ratio of the two
grades of fineness. The separation process was investigated by particle
size analysis and characterized by grade efficiency curves. The results
of the regenerable filter aid were compared to kieselguhr, and the
applicability was investigated by beer filtration tests at the Chair of
Process Engineering of Disperse Systems in Weihenstephan. Separation of
filter mud consisting of regenerable filter aids has a high innovative
potential for kieselguhr-free filtration especially with filter
performance comparable to kieselguhr and different sizes for optimal
adjustment for different beer types.
Alexander Scheidel was
born in 1987. He received degree a diploma engineer (M.S.) degree in
brewing and beverage technology from TU München-Weihenstephan, Germany,
in 2011. He began employment at the Chair of Process Engineering of
Disperse Systems in Weihenstephan as a Ph.D. student. The focus of his
work at the university is the filtration process with regenerable filter
aids.
VIEW PRESENTATION 136
