Technical Session 05: Malts and Grain Session
Birgit Schnitzenbaumer, School of Food and Nutritional Sciences, National University of Ireland, University College Cork, College Road, Cork, Ireland
Co-author(s): Jean Titze and Elke Arendt, School of Food and
Nutritional Sciences, National University of Ireland, University College
Cork, Cork, Ireland
ABSTRACT: The use of oats (Avena sativa L.) as an
adjunct in brewing has not only the potential to reduce the costs of raw
materials, but also to contribute to a unique beer flavor and aroma.
However, the replacement of malted barley with unmalted oats can also
have a negative impact on the quality and processability of mashes,
worts, and beers. The aim of this study was to evaluate the mashing
performance of unmalted oat cultivars used as adjuncts in brewing. For
this purpose, seven husked oat cultivars (Buggy, Curly, Galaxy, Ivory,
Lutz, Scorpion, Typhon) and one naked oat cultivar (NORD 07/711) were
fully characterized using confocal laser scanning microscopy,
lab-on-a-chip capillary electrophoresis, and standard methods specified
by the Mitteleuropäische Brautechnische Analysenkommission, European
Brewery Convention, or American Society of Brewing Chemists.
Furthermore, the rheological behavior of mashes containing 0, 20, and
40% oats of each cultivar was monitored during mashing by applying a
Physica MCR rheometer. The quality of worts obtained from
laboratory-scale mashing trials has been determined, particularly with
regard to their cytolytic, proteolytic, and amylolytic parameters. All
analyses were carried out in triplicate. Significant differences between
the studied oat cultivars with regard to their use as brewing adjuncts
were revealed. It has been found that naked oats are characterized by a
significant lower beta-glucan content and a higher starch content in
comparison to husked oat cultivars. In addition, the replacement of 20
or 40% malted barley with naked oats resulted in a constant extract
yield, whereas the use of up to 40% husked oats led to significant
extract losses.
Birgit Schnitzenbaumer successfully completed
an apprenticeship as assistant tax consultant and worked in this job
full-time before she studied brewing and beverage technology at the
Technical University of Munich in Weihenstephan, Germany. During her
studies, she completed several internships in breweries and did her
master’s thesis on the effect of malting on the protein profile of proso
millet (Panicum miliaceum L.) at the School of Food and
Nutritional Sciences of the University College Cork, Ireland. Birgit
graduated with a Dipl.-Ing. (M.S.) in brewing and beverage technology in
2009 and started her Ph.D. project on the application of novel and
industrial enzymes when brewing with unmalted cereals at the University
College Cork in November 2009.
VIEW PRESENTATION 18
