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Yeast: Difference between revisions
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Fusel alcohols are produced from the carbon skeletons of amino acids, and the effect of fusel alcohols on the finished product can be quite negative if present above or near their respective flavor thresholds.<ref name=fix/> | Fusel alcohols are produced from the carbon skeletons of amino acids, and the effect of fusel alcohols on the finished product can be quite negative if present above or near their respective flavor thresholds.<ref name=fix/> | ||
In many breweries producing South- | |||
ern German-style wheat beer, otherwise known as weissbier, after the installation of new cylindroconical fermentors, it is common for the beers to exhibit a noticeable decline in the bouquet characteristic of the style, which consists of primarily of compounds like isoamyl acetate (banana ester)[2]. The reason behind this somewhat diminished weissbier aroma is, among others, the high rate of yeast reproduction, which reduces the amount of the acetyl-coenzyme A available for ester formation. In addition, the high hydrostatic pressure in vertical vessels moderates the production of higher alcohols, thus reducing the numbers of reactants for the formation of esters. In short, the higher the liquid level is in a fermentation tank, the stronger the convection and homogenization, which results in a reduction in the formation of esters (fig. 4).<ref name=sacher2>Sacher, B., et al. "Some reflections on mashing – Part 2." ''Brauwelt International'', no. VI, 2016, pp. 392-397.</ref> | |||
The estery notes in beer have been observed to become more pronounced as the ratio of glucose to maltose tips in favor of glucose.<ref name=sacher2/> | |||
See: | See: | ||