ESB FG too high using Wyeast London ESB

[ntillemans]

I've made the same recipe several times over and have ended up 1.018 each time within 2 weeks. Suddenly, my latest batch is bottoming out at 1.024. I haven't done anything differently...haven't mashed at any higher temp or fermented at any lower temp. My starters were sized via the Mr Malty site. I'd like to be able to attribute this to something. But I just can't figure out what's causing this higher F.G. Any ideas whether I'm missing something here?

I've raised the temp and have been shaking the carboy daily for the past week. But all I've managed is a 2 point reduction in gravity (over the past week).

I'm about throw out my spreadsheets and flat out start praying to the beer gods...perhaps offering sacrifices...

[Henning1966]

Have you checked the calibration on your thermometer lately? If your mash temperature was low that could be it.

[ntillemans]

checked my hydrometer with tap water immediately after the surprise measurement. Got 1.000.

[ntillemans]

I kegged one 5 gallon batch and added an ounce of Goldings. Hoping that the dry-hopping will balance it out. I left the other 5 gallons in the carboy. Doubt the second 5 gallons will finish any lower, though.

[ntillemans]

Oh...sorry I misread your reply. My thermometer is calibrated fine.

The 5 gallons I dry-hopped tastes good (it's a bit sweeter than it should be...but perceptually for me it doesn't stand out as a problem, unless I really look for it). It seems like it should bother me more and that I should be making bolder attempts to fix it. But I don't really want to do anything drastic like beano...and I think adding champagne yeast would be overkill on a 1060 OG beer. I don't want to dry it out too much.

It seems balanced okay after dry-hopping. Thankfully that helped.

But it doesn't look good on paper. And it shakes my confidence in the consistency of my process.

Thanks again for your input.

[taskerm]

One thing that I have heard JZ recommend if you have a stuck fermentation is pitching another active small starter. Make a small starter (maybe a quart or so) with the same yeast that you have been using, wait for it to reach high kreusen, and throw that sucker in there. Just adding more yeast probably won't do the trick; the key is adding an active starter. I agree that something like Beano is a bad idea, since you have to heat up the beer in order to denature that stuff, so it will probably end up killing the body of your bitter.

[ntillemans]

Thanks for the advice. I remember reading something somewhere to that effect...but I didn't recall whether it was fine to add the same yeast or whether necessary to add a more attenuative/alcohol tolerant strain.

I think I'll give that a shot.

Seems this stuff doesn't stick with me until I run into a problem and then use the information to solve the problem at least once.

Good thing I brew a lot.

Thanks again.

[mthhurley]

Curious on repitching here...How would you calculate how much to pitch so as to not over-ferment it to the point of being dry?