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M-14: Open up a new era in evaluation of spring barley varieties

M. GASTL (1), W. Koenig (2), F. Rath (3); (1) Technische Universität München, Freising, Germany; (2) Braugersten-Gemeinschaft e.V., München, Germany; (3) VLB Berlin, Berlin, Germany

Raw Materials II
Saturday, June 7 - 10:00 a.m.-11:45 a.m.
Level 4, State Ballroom

For almost 50 years, Braugersten-Gemeinschaft e.V. provided the malting and brewing industries with comprehensive data and research results on quality malting barley. One focal point of the research has been constant evaluation of newly approved varieties. With the 2012 harvest, reorganization was made in the malting barley variety evaluation using isothermal 65°C mash instead of the Congress mashing procedure. Malt quality was evaluated by amylolytic (alpha-amylase, beta-amylase, degree of fermentation, extract), proteolytic (protein content, soluble nitrogen, Kolbach index, FAN), and cytolytic (beta-glucan, friability, viscosity) criteria using standard MEBAK methods. In order to evaluate the influence of mashing procedure on malt quality parameters, the Berliner Programm 2011/2012 and 50 industrial samples (harvest 2013) were investigated on the basis of Congress mash and in parallel using the isothermal 65°C mashing procedure. The change from the Congress mash to the isothermal 65°C mashing procedure resulted in decreases and increases in some values/criteria, as well as shifts in the standard values of well-known malt specifications. Based on a collected database, the changes, consequences, and new evaluation criteria were presented. Formerly cytolysis was the limiting factor for reducing germination time. Due to the changes caused by the success of the breeding solution and as a consequence of the higher degree of modification of the varieties, the MEBAK standard malting procedure was adapted in 2006 (45% soft degrees, 15°C germination temperature), and the germination time was shortened by 1 day to 6 days (steeping and germination time). With this adjustment, Braugersten-Gemeinschaft e.V. has again reacted to the ongoing progress in breeding, as well as the commonly practiced mashing procedures. A small-scale mashing procedure suitable for predicting malt specifications, modification characteristics of a variety, and wort quality is required. Assuming good malt quality, high-temperature short-time mashing is a commonly applied procedure. The isothermal 65°C-mashing procedure focuses on amylolytic modification, as well as cytolytic (beta-glucan) criteria. Therefore, this method provides better applicability in practice.

Martina Gastl apprenticed as a brewer and maltster from 1994 to 1996 in Klosterbrauerei Andechs, Germany. She studied brewing and beverage technology at Technische Universität München-Weihenstephan, Germany. She graduated as an engineer in 2002. From 2002 until 2006 she completed her Ph.D. degree concerning “Technological Influence on Lipid Degradation in Terms of Improvement of Beer Flavor Stability.” After graduation she worked as a scientific employee and is currently an assistant professor and head of the Raw Material Research group at the Lehrstuhl für Brau- und Getränketechnologie in Weihenstephan. She currently is finishing her post-doctoral lecture qualification; her research interest involves “Characterization and Interaction of Flavor Active Taste Compounds in Cereal Based Beverages Influencing Beverage Harmony.”