RRC ID 4624
Author Okada Y, Iimure T, Takoi K, Kaneko T, Kihara M, Hayashi K, Ito K, Sato K, Takeda K.
Title The influence of barley malt protein modification on beer foam stability and their relationship to the barley dimeric alpha-amylase inhibitor-I (BDAI-I) as a possible foam-promoting protein.
Journal J Agric Food Chem
Abstract The foam stability of beer is one of the important key factors in evaluating the quality of beer. The purpose of this study was to investigate the relationship between the level of malt modification (degradation of protein, starch, and so on) and the beer foam stability. This was achieved by examining foam-promoting proteins using two-dimensional gel electrophoresis (2DE). We found that the foam stability of beer samples brewed from the barley malts of cultivars B and C decreased as the level of malt modification increased; however, the foam stability of cultivar A did not change. To identify the property providing the increased foam stability of cultivar A, we analyzed beer proteins using 2DE. We analyzed three fractions that could contain beer foam-promoting proteins, namely, beer whole proteins, salt-precipitated proteins, and the proteins concentrated from beer foam. As a result, we found that in cultivar A, some protein spots did not change in any of these three protein fractions even when the level of malt modification increased, although the corresponding protein spots in cultivars B and C decreased. We analyzed these protein spots by peptide mass finger printing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. As a result, all of these spots were identified as barley dimeric alpha-amylase inhibitor-I (BDAI-I). These results suggest that BDAI-I is an important contributor to beer foam stability.
Volume 56(4)
Pages 1458-64
Published 2008-2-27
DOI 10.1021/jf0724926
PMID 18237135
MeSH Beer / analysis Beer / standards* Electrophoresis, Gel, Two-Dimensional Hordeum* / chemistry Hordeum* / genetics Plant Proteins / analysis Plant Proteins / chemistry* Protein Denaturation Species Specificity alpha-Amylases / antagonists & inhibitors*
IF 4.192
Times Cited 49
Barley NA