Stopping Infections With Potassium Sorbate/Metabisulfite - Beer, Wine, Mead, & Cider Brewing Discussion Community.

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Dec 27, 2013
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I brewed a 1.06ish Saison, and pitched WLP530, and then top-cropped the yeast for a Westmalle 8-ish dubbel. Lo and behold, the saison is showing signs of infection (bubbles that weren't there a few days before, the filmy grey-white clumps that crumple up when touched with the hydrometer, very tart cider-tasting gravity sample that differs from how it tasted a week ago).

However, the dubbel fermented to the gravity I expected, and tastes great. Since I top-cropped yeast from the infected saison batch, I expect that this batch will be infected as well.

Since I have no off-flavors or symptoms of the infection, can I kill the remaining yeast/bacteria with a combination of potassium sorbate and metabisulfite? My thought is this would prevent the bacteria from messing up the beer. I would then add a 1/2 pack or so of dry yeast at bottling time to provide sufficient yeast for bottle carbing.


Sometimes I have to remind myself
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May 13, 2014
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Midwest USA
If this were the beginning of fermentation and little or no alcohol had been produced I'd say "probably" but once it gets to the point you're at, adding those compounds makes the liquid pretty much indefinitely intolerable to yeast.

Do you have a friend with an empty keg that doesn't mind you stopping over pretty much whenever you want?