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This study investigated whether the consumption of a diet in which high-beta-glucan barley replaced rice would reduce the visceral fat area as well as the serum low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in hypercholesterolemic Japanese men. A randomized, double-blinded, placebo-controlled intervention study was conducted in 44 hypercholesterolemic Japanese men with a body mass index (BMI) >22 kg/m2. The subjects were randomly assigned to groups consuming either rice (placebo group) or a mixture of rice and pearl barley with a high beta-glucan content (test group, 7.0 g beta-glucan per day) for 12 weeks. Blood samples were taken, and CT scan obtained before the trial and every four weeks during the trial. The pearl barley intake significantly reduced serum concentrations of LDL-C (P = 0.041) and TC (P = 0.037) during the trial. Significant differences between the test and placebo groups were found for the visceral fat (P = 0.039), BMI (P = 0.015), and waist circumference (P = 0.011) at the end point. The consumption of pearl barley with a high beta-glucan content reduces not only LDL-C but also visceral fat area. [ABSTRACT FROM AUTHOR]

Hokkaido-specific malting barley varieties have been developed to improve the grain yield, disease resistance, malting quality, and brewing quality. In this report we describe the breeding and evaluation of brewing quality of a hulled two-row malting barley ( Hordeum vulgare L.) variety 'Satuiku 5 go' lacking lipoxygenase-1 (LOX-1-less). 'Satuiku 5 go' was evaluated in the joint field trials for malting barley in Hokkaido from 2016 to 2018. 'Satuiku 5 go' exhibited 11% higher grain yield and 7.6 cm shorter plant height than the control variety, 'Ryohfu'. However, the disease severity of Fusarium head blight (FHB) in 'Satuiku 5 go' was higher than in 'Ryohfu'. For malting quality, 'Satuiku 5 go' exhibited higher diastatic power, soluble nitrogen content, and fine extract content, and lower wort β-glucan content than 'Ryohfu'. 100-litter pilot scale brewing trials were conducted with 'Satuiku 5 go' and 'Satuiku 2 go' as a control variety, also a LOX-1-less variety, and no clear differences were observed., (Copyright © 2024 by JAPANESE SOCIETY OF BREEDING.)

Proteome analysis provides a way to identify proteins related to the quality traits of beer. A number of protein species in beer and wort have been identified by two-dimensional gel electrophoresis combined with enzyme digestion such as trypsin, followed by mass spectrometry analyses and/or liquid chromatography mass/mass spectrometry. In addition, low molecular weight polypeptides in beer have been identified by the combination of non-enzyme digestion and mass analyses. These data sets of various molecular weight polypeptides (i.e., proteomes) provide a platform for analyzing protein functions in beer. Several novel proteins related to beer quality traits such as foam stability and haze formation have been identified by analyzing these proteomes. Some of the proteins have been applied to the development of efficient protein or DNA markers for trait selection in malting barley breeding. In this chapter, recent proteome studies of beer and wort are reviewed, and the methods and protocols of beer and wort proteome analysis are described.

Foam stability is an important quality trait of beer. Our previous results of two-dimensional gel electrophoresis (2DE) analyses of beer proteins implied a relationship between barley dimeric alpha-amylase inhibitor-1 (BDAI-1) and beer foam stability as judged by the NIBEM-T analyzer. To develop a novel prediction method of beer foam stability under different conditions of barley cultivar and malt modification, multiple linear regression analysis was applied. The spot intensities of major beer proteins on 2DE gel were quantified and used as explanatory variables. The foam stabilities of 25 beer samples each brewed from malt with different malt modification in one of the three cultivars (cultivars A, B, and C) were explained by the spot intensities of BDAI-1 at the 5% significance level ( r = 0.421). Furthermore, two other major protein spots (b0 and b5) were observed on the 2DE gels of Japanese commercial beer samples with different foam stability. Then, multiple regression for foam stability was calculated using these three spot intensities as explanatory variables. As a result, 72.1% of the beer foam stability in 25 beer samples was explained by a novel multiple regression equation calculated using spot b0 and BDAI-1 as positive explanatory variables and spot b5 as a negative variable. To verify the validity of the multiple regression equation and the explanatory variables, the beer foam stability in practical beer samples was analyzed. As a result, 81.5% of the beer foam stability in 10 Japanese commercial beer samples was also explained by using spot b0 and BDAI-1 as positive explanatory variables and spot b5 as a negative variable. Mass spectrometry analyses followed by database searches revealed that protein spots b0 and b5 were identified as protein Z originated from barley and thioredoxin originated from yeast, respectively. These results confirm that BDAI-1 and protein Z are foam-positive factors and identify yeast thioredoxin as a possible novel foam-negative factor.

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.