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View Full Version : Stuck Ferment, Possibly Infected?



andyman30
06-30-2015, 07:33 PM
Hey all.

Long story short I replaced a previous distiller about a week ago and am in the process of trying to play investigator as to what their process was like.

That being said, we have a 15bbl batch that has entered its 10th day of fermentation and was stuck at 12% brix from an OG of 16% brix. After running some preliminary tests on it, the pH turned out to be a whopping 3.1.
Although there is a high amount of specialty malt in the batch recipe, nothing I know of short of infection can possibly get the pH that low. Our water is fine, and passes the test on every calculator I plug it into.

It was fermenting a little hot, around 85F, although I don't believe that's anything to worry about as far as stopping a fermentation.

When I peeked inside the fermentor today there was no biofilm or any such indicator of lacto or pedio that I could see. The mash tastes tart but nothing close to a sour mash. The yeast they pitched was EC-1118 from Lallemand.

Is there anything else I can do to figure out what the heck this guy did or if its possibly infected? I raised the pH back up to 5 and repitched a the right amount of yeast today, not knowing the amount that was originally pitched either.

Thanks for any suggestions.

tjc27
07-01-2015, 08:25 AM
Sounds like infection, because the PH is so low the yeast didn't finish. Unless of course the PH was way off going into the fermenter.

dick murton
07-01-2015, 12:59 PM
Assuming it was meant to have been pitched with yeast, it sounds as though insufficient or no yeast was added. Or if yeast was added, it wasn't viable.

If the guy knew he was going (not of his own choice for whatever reason) when he brewed it, perhaps it was deliberate sabotage.

dick murton
07-01-2015, 01:01 PM
I meant to add, get rid of it ASAP and give extra cleans to reduce the risk of contamination of subsequent "brews"

andyman30
07-06-2015, 12:30 PM
Thanks for the input, I dumped it last week and sanitized the heck out of it and everything around it.

I finally got a hold of him and it looks like his pitch rate was .31 M / ml / P, which is what I'm assuming the issue was.

I'll keep you posted if it mysteriously stops again, mashing in sometime this week.