J. YU (1), J. Liu (1), W. Fan (1), J. Dong (1), S. Hu (1), S. Huang (1), S. Huang (1), H. Yin (1);
(1) State Key Laboratory of Biological Fermentation Engineering of Beer, Tsingtao Brewery Co. Ltd., Qingdao, China
It is well-known that the protein components of malting barley are correlated with barley variety and growing regions. This study examined the differences in protein molecular weight distribution (PMWD) among 18 malting barley varieties by capillary gel electrophoresis with 26 samples of 8 Canadian malting barley varieties (CDC Copeland, AC Metcalfe, CDC Meredith, Newdale, Legacy, AC Bountiful, Sister, and Select) and 9 Australian malting barley varieties (Baudin, Gairdner, Schooner, Commander, Sloop, Vlamingh, Flagship, Hindmarsh, and Hamelin). The test results showed that there were some significant differences in protein molecular weight distribution between Canadian and Australian malting barley. The proportion of high molecular weight protein (e.g. 50–100 kDa molecules) for Canadian barley (16.74%–46.06%) was significantly higher than that for Australian barley (4.26%–16.16%). And the proportion of low molecular weight protein (e.g. less than 10 kDa molecules) for Australian barley (23.53%–41.86%) was significantly higher than that for Canadian barley (12.28%–32.54%). On the other hand, the PMWD of difference among the Canadian varieties was recorded: CDC Copeland’s PMWD was similar to AC Metcalfe, and the 50–100 kDa protein proportion for the two varieties was highest among the 18 malting barley varieties. However, the proportions of 10–20 kDa, 20–50 kDa, and 50–100 kDa for AC Metcalfe and CDC Meredith were 31.6%, 16.01%, and 40.28% and 40.91%, 11.78%, and 16.74%, respectively. Compared with SDS-PAGE, the capillary gel electrophoresis has better resolution and accuracy, as well as higher degree of automation; this method could be used for screening barley varieties with high molecular weight protein, which offers better beer foam stability, and for the identification of malting barley varieties.
Junhong Yu is a vice director of the R&D Center of Tsingtao Brewery Co. Ltd. She obtained her doctor of science degree from the Ocean University of China in 2001. She joined Tsingtao Brewery Co., Ltd. in 1997 after obtaining her M.Eng. degree from Jiangnan University in the same year, and began her 17 year research career. Her research interests focus on beer foam and colloid stability, protein analysis, lipoxygenase (LOX), starch-degrading enzymes, etc. She attended the ASBC Annual Meeting in 2007 to give an oral presentation and WBC 2012 to present a poster.