Pure yeasts selected from fermenting pear juice from the Lower Austrian Mostviertel region and their suitability for pear wine production

Abstract

If spontaneous fermentation is not carried out, commercially available pure yeasts, which are actually intended for the production of wines from grapes, are often used for the production of pear wines. Pear juice is clearly different from grape juice, e.g. due to the significantly greater difference in the ratio of fructose to glucose or the absence of tartaric acid. For this reason, the commercially available pure yeasts may be suboptimal for pear wine production. They were therefore compared with yeasts isolated from pear juice that had been purely cultivated with regard to their suitability for pear wine production. Overall, the yeasts isolated from fermenting pear juice proved to be more suitable for pear wine production. This is not only the result of the tasting of the wines fermented in 25-litre glass flasks, but also follows very clearly from the multivariate comparison both for the basic chemistry and for the spectrum of aroma components. Density and malic acid concentration were higher in wines produced with yeasts selected from fermenting pear juice. More substances from the "fruity" and especially "fruity-sweet" flavour groups were found in these wines in comparatively higher concentrations. For pear wine production, it is therefore advisable to isolate suitable yeasts from pear juice for pure cultivation.