Kettle sour got too hot...

[FoxFeud]

I use a heating element to do kettle sours and today my roommate knocked one of the temperature probe wires, causing the heating element's relay to stay switched on. By the time I noticed, about three hours after it had been stuck on, the wort had reached 160F from the 110F it had been set at. I had pitched Wyeast 5335 Lactobacillus when the wort hit 110F about 36 hours ago, and was planning to let it keep sitting until Monday night.

Does anyone know if there could be some bacteria left alive? I fixed the temperature regulation and am letting the temperature fall as I type but I'm curious to know if I should expect any subsequent souring to take place.

 

[madscientist451]

I'd say your lacto is cooked, but maybe 36 hrs was enough to get the sour you were looking for. I'd go to boil now, there's no point in waiting.

 

[FoxFeud]

Thanks for the response, I figured there wasn't much hope for it. Unfortunately I have a Brett starter currently on the stir plate that I set up the same time as the kettle sour. The plan was for them both to be about ready on Monday.

I just remembered that I have some 2-row sitting around, would there be any harm in throwing some of that in and hoping for the best? If I'm stuck with the wort for the next ~48 hours I might as well try to shave some points off the pH... even if I am too cheap to shell out for more Lacto.

 

[TAK]

Have you tasted or tested it for acidity?

 

[FoxFeud]

Have you tasted or tested it for acidity?

I didn't taste much tartness, looks like the pH is in the low 4s but I just have strips so it's hard to say exactly. I was hoping to hit something closer to 3.5.

 

[TAK]

Just wanted to be sure you weren't going solely off of time. If it's not tart enough, that's a bummer. I can't vouch for using culture from grain. I probably wouldn't, I'd say RDWHAHB and it is what it is, but you could give the grain a shot.

 

[505-Brewer]

Im a big fan of grain. I've always made a starter 1st for piece of mind but I've never had one go off for me. It is my experience the grain lacto is very sensitive to hops. Even 5 ibus has been enough such that it only gets to pH 3.8 (tart but not sour). I'd say use 1-2 cups of uncrushed grain and hold the temp if you have CO2 give it a purge before hand.

 

[FoxFeud]

Thanks for the advice everyone, I ended up pitching a cup of grain once the temperature dropped back to the controlled range. If nothing else it will be interesting to see what the grain can do with the pseudo-soured wort with the temperature control.

All in all, the $13 lacto pouch is not a bad price to pay for the lessons of a) maintaining vigilance over a kettle sour that other people might bump into and b) writing failsafe code that resorts to shutting off the heating element when sensors aren't responding as expected.