Department of Fermentation and Cereals Technology, The Faculty of Biotechnology and Food Science, Wrocław University of Environmental and Life Sciences, 50-630 Wrocław, Poland.
Molecules. 2022 Jun 21;27(13):3971. doi: 10.3390/molecules27133971.
Dark malts used in the production of brewing wort affect the ethanol fermentation process, the phenolic content, antioxidant capacity and the physiology of yeast cells. An innovative element of this research is the combination of investigating the effect of beer wort color modulated by the use of dark specialty malts on the course and effects of fermentation and the characteristics of post-fermentation yeast biomass of brewer's strains with different characteristics. Dark and pale beer were obtained. The beers had different ethanol contents (4.51-5.79% /), resulting from real (62.29-80.36%) and apparent (75.37-98.26%) attenuation levels. Metabolic and morphological differences were demonstrated in the brewer's yeast strains used. var. was distinguished by its ability to ferment dextrin, resulting in the highest ethanol content in beers. The total phenolic content in beer depends on the color of the wort and the yeast strain used (244.48-547.56 mg of gallic acid/L). Dark beers show higher ferric ion reduction ability (FRAP) and antioxidant capacity (ABTS) than pale beers fermented with the same yeast strains. Through biomass analysis, differences in yeast cell physiology depending on yeast strain and beer wort color were also revealed.
在酿造麦汁的过程中使用深色麦芽会影响乙醇发酵过程、酚类含量、抗氧化能力和酵母细胞的生理学特性。本研究的一个创新点是，结合研究使用深色特种麦芽调制啤酒色泽对发酵过程和效果的影响，以及不同特性的啤酒酵母菌株在后发酵酵母生物量特性的影响。得到了深色和浅色啤酒。这些啤酒的乙醇含量不同（4.51-5.79%/v），这是由于实际（62.29-80.36%）和表观（75.37-98.26%）衰减水平的不同。所使用的啤酒酵母菌株表现出代谢和形态上的差异。var. 因其能够发酵糊精而区别于其他菌株，导致啤酒中的乙醇含量最高。啤酒中的总酚含量取决于麦汁的颜色和所用的酵母菌株（244.48-547.56mg 没食子酸/L）。与使用相同酵母菌株发酵的浅色啤酒相比，深色啤酒具有更高的铁离子还原能力（FRAP）和抗氧化能力（ABTS）。通过生物质分析，还揭示了不同酵母菌株和啤酒麦汁颜色对酵母细胞生理学的影响。
