This brings us back to the bread yeast. Most bread yeast will ferment alcohol up to about 8% with ease, but when trying to produce alcohol beyond this level, the bread yeast begin to struggle, very often stopping around 9% or 10%. This is short of what weââ¬â¢d like to obtain for almost any wine.
Another reason making wine with bread yeast is not a good idea is that bread yeast do not clear out very readily or settle very firmly, either. They typically will form a low layer of hazy wine in the bottom of the fermenter that will never completely clear out.
Even more importantly, bread yeast produce alcohol that is plagued with a lot of off-flavors. The bread yeast becomes so stressed and has to work so hard that off-flavored enzymes and fatty acids are produced along with the alcohol.
There are several other issues with using bread yeast to make your wine, but these are the big ones: the alcohol, the clearing, and the flavor.
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