mold in beer

Reads 1374 • Replies 6 • Started Wednesday, January 16, 2013 3:15:14 PM CT

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beers 4 º 15:15 Wed 1/16/2013

OK. This is kind of related to my previously posted fruit beer question. I've purchased the requisite raspberries to add to my fermentor near the end of the primary. I froze them last weekend. The wife says "what if there was mold on them?" I didn't know to wash them before freezing, cause, unlike her, I didn't major in biology.

I now wish she's said something sooner, but my question is... if, by chance, there IS a bit of mold, (and I saw no evidence of it as I emptied them from eight 12 oz. containers) will the freeze kill off any possible mold, or will I be risking mold infection in my fermented brew? I'm hoping the alcohol will knock the mold down, or at least stop it from affecting my flavor. Should I thaw and rinse the berries? Boil them for a minute and pitch in the carboy? Any suggestions? I plan to add them on Thursday evening so I'm hoping to hear something soon.


beers 5877 º places 412 º 15:20 Wed 1/16/2013

Hmmm, if your wife is a biology major maybe asking her would be the first step to knowing if mold survives freezer temperatures. I wouldn't be especially concerned, berries are naturally covered with mold (spores) and these do not have a tendancy to grow in an environment where yeast is well established in tremendous numbers and the environment is already alcoholic.

Another thing to keep in mind is if the worse comes to the worst, I've had homebrew that had mold on it (not mine but someone else's) that turned out just fine when he racked from below. I don't think extra manipulation of the berries will do anything in your favor, but that's just IMO.

beers 1511 º places 103 º 15:42 Wed 1/16/2013

Hardywood had some interesting stuff happen with their Virginia Strawberry that they determined was due to a mold on the strawberries they used.

beers 9454 º places 536 º 16:01 Wed 1/16/2013

I wouldn't sweat it - many molds can survive freezing but fermenting/fermented wort is not an especially hospitable environment for yeast.

beers 4 º 16:03 Wed 1/16/2013

Well, the wife says she wasn't a microbiology major, so her guess is as good as everyone else's. I will toss them in and see what happens. If it turns out bad I'll blame the unconfirmed existence of mold spores.

beers 217 º 16:04 Wed 1/16/2013

You might be able to tick the basement aroma box, but it will be fine either way. You added it after fermentation and the booze will probably kill the mold.

08:56 Wed 2/13/2013

its very scary to hear mold in did you manage to notice it?

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