Sulfate Metabolism during Fermentation1
作者:
HysertD. W.,
MorrisonN. M.,
期刊:
Journal of the American Society of Brewing Chemists
(Taylor Available online 1976)
卷期:
Volume 34,
issue 1
页码: 25-31
ISSN:0361-0470
年代: 1976
DOI:10.1080/03610470.1976.12006180
出版商: Taylor&Francis
关键词: Fermentation;Hydrogen sulfide;35S-labeling;Sulfate;Sulfur dioxide
数据来源: Taylor
摘要:
Overall sulfur balance and sulfate metabolism during fermentation of brewery wort by ale and lager yeast have been studied by [35S]sulfate labeling experiments. Ale yeast derived 40 and 27% of the total sulfur assimilated during stirred flask and unstirred column fermentations, respectively, from wort sulfate. The corresponding values for lager yeast were 41 and 21%. The contributions of sulfate to H2S evolved in the fermentor gases, and to medium SO2 formed during fermentation, have been examined. Ale fermentations produced<μg S of fermentor gas H2S/I. medium and<0.2μg S of medium SO2/I. medium. Stirred flask lager fermentations evolved an average of 62μg H2S/I. of medium, 72% of which was derived from sulfate. Sulfate-derived H2S constituted 64% of the total H2S evolved during unstirred column fermentations (130μg H2S/I. medium). The effects of individually added amino acids (L-methionine, L-threonine, and L-cysteine) and heavy metals (Fe, Cu, and Zn) have been studied and are discussed in terms of literature results and yeast sulfur metabolism. The total bound SO2levels averaged 0.17μgS/g and 11μgS/g in beer from stirred flask and unstirred column lager fermentations, respectively. Radiochemical tracer experiments showed that all of the SO2formed in the latter experiments was derived from wort sulfate.
点击下载:
PDF (741KB)
返 回