here - the 34th European Brewery Convention

P18
Beta-glucan hazes - what's the problem
Cecilia Damiani 1 , Karin Pawlowsky 1 , Giuseppe Perretti 2
1 Campden BRI, Nutfield, United Kingdom, 2 Università di Perugia, Perugia, Italy
In some instances beer haze is caused by beta-glucan molecules. Although this carbohydrate haze
has commonly been associated with poor malt quality or mashing problems, it can also originate from
the yeast cell wall. Indeed, with the increased use of centrifuges for yeast separation and high gravity
brewing, yeast cells can be exposed to stresses resulting in damage to cell walls and release of betaglucans.
Until recently, there was no simple test to distinguish between a yeast and malt beta-glucan
haze, which has made trouble shooting the haze problem difficult. However, we have now solved this
technical challenge and describe here a novel protocol for the isolation/examination of beta-glucan
hazes and determination of whether they originate from yeast or barley.
P19
Changes of metal concentration in beer production and their Influence on the mechanism for
haze formation
Annika Burmeister 1 , Adelina Calean 2 , Thomas Kunz 3 , Frank-Jürgen Methner 3 , Peter Winterhalter 1 ,
Peter Fleischmann 1
1 TU Braunschweig, Institute of Food Chemistry, Braunschweig, Germany, 2 TU Braunschweig, Institute
Geoecology, Braunschweig, Germany, 3 TU Berlin, Institute of Biotechnology, Berlin, Germany
Chill haze in beer causes an economical loss for the brewing industry. Due to the precipitation of
protein-polyphenol-metal complexes under inadequate storage conditions, consumers confound these
hazes with mold and its associated health risk.
This work deals with the development of concentrations of Mn, Cu, Zn and Fe in beer raw materials,
beers and their final concentrations in isolated beer hazes (analyzed via ICP-MS and ICP-OES).
Independent from the raw materials used the concentrations of Fe, Mn, Cu and Zn in beers strongly
depend on the steps of brewing process. Metal concentrations in the resulting hazes are 17 fold higher
for Fe, 4 fold higher for Cu, 6 fold higher for Zn and 30 fold higher for Mn than in the original beers.
P20
Improving your draught beer quality
Johannes Tippmann 1 , Simon Henke 2 , Heinz Dauth 3 , Thomas Becker 1
1 Technische Universität München, Lehrstuhl für Brau- und Getränketechnologie, Freising, Germany,
2 Technische Universität München, Lehrstuhl für Verfahrenstechnik Disperser Systeme, Freising,
Germany, 3 Hochschule Ansbach, Fakultät Ingenieurwissenschaften, Ansbach, Germany
For years, people talk about the quality of draught beer and their potential for improvement.
Developments in dispensing systems are, however, in most cases, just to improve the appearance of
the equipment. The most important aspect for a brewer - hygiene - is often neglected. As a
consequence, the quality of beer is destroyed in the last few meters, just before the consumer enjoys it.
We carried out extensive studies on construction, cleaning and maintenance of dispensing equipment.
It was found here that the microbial load in draught beer could be reduced by good hygiene practices
in 6 weeks by more than 90%. The investigation of design aspects also brought strong improvements.
Here also immense hygienic improvements were observed.
The presentation shows these findings and gives advice, such as fast recontaminations can be