What made my beer/gruit go sour?

5 gallons of beer, 5 gallons of gruit, sitting side by side in 7.9 gallon plastic fermenters. One a recipe I made up, the other a kit that I brew all the time, one of my favorites. Both have the same awful sour taste and smell to them. Only way to drink them is to hold your nose and do it fast, then it feels like you just did a shot of nasty whiskey.

They are still in the fermenters, been at least 2 weeks, I think. Lift the airlock on either one and they smell bad. Both actively fermented, didn't quite blow off the airlocks but close.

I am thinking, I live in Florida, getting warm, that my fermenting temperatures got too high. I have cooled them off now but fear it is too late to save the 10 gallons. It got hot in the house for a few days but there was nothing I could do about it at the time. Do you think my diagnosis of the problem is correct? Fermenting temps just got too high?

And any ideas on a prognosis?

How hot did it get, and what yeast?

Room temp got to about 80 degrees, this was during active fermentation on both of them. I'm sure inside the fermenter was much higher. The yeast was Safale US-05. In addition, both reused yeast from the same previous batch(which turned out great). I washed the yeast from a 5 gallon batch and reused it to pitch in both batches. Not sure if that is related, I have done the same thing before with no problems at all.

80° ambient could certainly throw some off flavors, but bad smell and sour taste sounds like infection to me. I'd suspect sanitation related to your yeast washing led to some uninvited guests hitching a ride with your yeast.

ktblunden said:

80° ambient could certainly throw some off flavors, but bad smell and sour taste sounds like infection to me. I'd suspect sanitation related to your yeast washing led to some uninvited guests hitching a ride with your yeast.

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You could very well be right, I can not say that my sanitation practices were perfect. I do tend to cut corners. Hmmm... maybe fruit flies dropped me a little gift? Around the same time, I had a little problem with fruit flies in the kitchen.

On the apple mint gruit batch, it was the one I tasted first, tasted like sour apples so I added 2 lbs of brown sugar and some fresh yeast. Maybe that will kill whatever got into it? Brown sugar because sour apples, apple pie, you start with sour apples and add brown sugar. Even thought about adding cinnamon to that batch.

The other one, my regular session pale ale, the stuff I brew all the time, haven't tried anything to try and fix that one. Hmmm.... poor prognosis on both of them?

If the primary ferment is over, I'd let the temperatures ramp up again and let the yeast try to clean up. You might have good product in your future, but it will take a while for the yeast to undo a bad ferment. I'd tuck the fermenters away someplace and brew something else for a while and come back to these in a few weeks or even months.

No hops. My gruit was like unsweet lemonade. Kinda good though. Tart lemony and pretty refreshing. I had bottles conditon in the 80's at the time after bottleing also,thought it was maybe from that.Could be a combo of not using hops and warm bottle conditon. I need to dig one of those up and have a few,I considered mine an ok summersession beer. I questioned the age of my gale/yarrow also.Thinking my lhbs had old gale and I got dried yarrow from a healthfood store in a bulk jar.Supposibly fresh yarrow is ideal so I havent had that to compare it to.

Gruits, especially with yarrow, do tend to be a bit tart in my experience; however, given that both your beer and gruit have an unpleasant tartness to them, I would be much more suspect that you have a lactobacillus infection...time to sanitize the $h!t out of everything, and perhaps even ditch/replace things that can be (stoppers, tubing, etc.)

At first I did think it was the no hop thing. Until I opened the pale ale, got a whiff and thought I opened the wrong fermenter. I have searched lactobacillus, thanks for that suggestion. Not too long ago, a different batch did come out badly, I called it my sour lemonade pale ale or something like that. Ended up adding strawberries and more sugar, turned it into a wine type thing. Actually was very good and drank it all before it probably aged properly. I wonder if the possible contamination carried over, from poor sanitation. I do sanitize but I'm not anal about it and I do cut corners sometimes.

If the plastic has scratches on the surface from scrubbing, etc., it can be difficult to sanitize, but overall, there's no reason specifically why plastic would be harder to clean and sanitize than glass if you're doing best practices...

I think the starters I made kind of taste like gruit. As far as the pour off beer sample I tried.

My guess would be the yeast washing as well. If it was only the gruit that was sour I would say it's because of no hops, but since you have it in the pale ale as well that's doubtful. I've brewed three gruits in my time and only one was sour (but getting pretty nice now at around 9 months in the bottle). An 80 degree ambient temp at the beginning of fermentation could certainly throw off some interesting flavors too. If you have the space and fermenters available I would let it ride out a little bit. Two weeks just seems too early to call to me.

Yeah, I am going to just let them ride. They are both very, very young. Thanks for the help. Probably was the yeast washing, I didn't actually boil the water, just used tap water. Has worked fine in the past but I know I was pressing my luck. I don't see any kind of pellicles forming, they don't look infected, maybe it will clear up with time. Not sure why I thought it was the temps at first, should have known it was probably the yeast. Well, those are the 2 things they had in common, so had to be one or the other.

I'm actually kind of happy it happened to both of them, otherwise I would have blamed the gruit and called it a bad experiment. And slight infections can clear themselves up with time, right?