Not bad beer, just good vinegar...

Okay, this one hasn't happened in a long time (to me anyhow). I have a cherry wheat in mini-kegs and tapped one after a couple weeks.
Worst beer ever...
I have had malt vinegar on fish and chips that was not as strong as this. I tapped the other mini-kegs hoping it was a fluke. Nope..just as crappy. My only saving move was to open an Ale I had made about a month ago. It was much better, so I drank a couple to get that vinegar taste out. So...what happened? Everything was clean, followed the recipe, The only thing I can think of was the priming sugar was a bit too heavy, as I found out late you only use half normal for a mini-keg. What say all of you?

Hmm... too many sour cherries?

What was the recipe?

Sour beer that tastes like vinegar is a sure sign that the beer has become infected. I'd give your fermenters, airlocks and syphon tubing etc a long soak in a bleach solution.

If there's no doubt in your mind that it is a vinegar taste and not a bitter-green beer taste that would mellow with maturity-ditch the beer and soak your kegs in bleach too, as they are ss, dont leave it in there too long 20mins should be enough, its harmless at santiation concentrations for relatively short periods but I tend to be fairly cautious.

Of course the infection could be down to the fruit, did you sanitise that?

Yeah, the fruit was boiled. I tend to go with some bad bugs. It's a shame, but it's gotta go. I'm not so sure I like this mini-keg thing, might have to go to corny kegs and the whole shmeer. Well, one bad batch after this long.

Its not as important to boil the fruit as it is to get the temperature above 80 deg c for at least 15 mins. This can be done by pouring boiling water over the pulped fruit or raising the temperature in a microwave or on the stove to 80 deg c and holding it for 15 mins. (at least thats the theory, I may get back to you on that as i'm going to be adding cherrys to an experimental brew in a week or so).