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The effect of yeast propagated at different aerationconditions on yeast physiology, fermentation ability, and berquality was investigated using three strains of Saccharomycescerevisiae. It was shown that yeast cels grown undercontinuous aeration conditions during propagation were almosttwo times higher as compared with discontinuous aerationconditions. The maximum of cell growth of all samples reachedbetwen 36 h and 48 h. The concentration of trehalose wasincreased under continuous aerated yeasts, whereas glycogenwas decreased. It was also observed that the concentration ofglycogen and trehalose in yeast cells had no direct effect onsubsequent fermentation ability. The effect of yeast propagatedunder diferent aeration conditions on subsequent fermentationability was diferent from yeast strains, in which the influenceyeasts might regain its original characteristics in the followingfermentations. Generally, continuously propagated yeast hada positive effect on beer quality in subsequent fermentation.Hence, the concentration of aroma compounds obtained withyeast propagated under 6 l/h for 48 h aeration was lower thanthose grown under other aeration conditions in the bottomyeasts; in particular, the amounts of phenylethyl alcohol,ester, and faty acids were decreased.