Crazy temp jump in fermentor

Hello all,

I am fairly new brewer and brewed my first all grain batch on Saturday. It’s an Irish Red Ale following the Brewing Classic Styles recipe.  ;D

Pretty much hit all the numbers right except the OG with ended up high at 1.070 (too long of a bowl). After pitching my 1L starter at 64F and 12 hours I had good sign of fermentation and stabilized temp of 66F. Due to our house being pretty cold and the temp swings, I wrapped the carboy in a jacket. I now know the insulation will cause the temp to rise significantly when the fermentation is really ramped up. This morning the temperature was 76F (i have removed the insulation and hopefully when I get home it has lowered).

My question is what kind of off flavors might I expect from being 8 hours or so over the ideal temperature?

Is there risk of ruining the batch due to the spike?

Thanks in advance for your advice.

Brian

It won’t be ruined by any means, but it may have some flavors you don’t really want. An extra week or two in the fermenter will help, letting the yeast clean up as many by-products as possible.

With the higher temps you can expect more esters to be produced by the yeast normally resulting in more fruity flavors.  It may not have as “clean” of a profile as you were going for.  Also with the high OG, you might get some Fusel alchohol, which is evident by more of a “hot” alcohol component.  I would agree with the above post telling you to leave it in primary for a while longer to let the yeast clean up as much by-product as possible.

Thanks for the quick response.

I have a couple questions:

  1. at what temp do you let the fermentor sit to allow the yeast to clean up?

  2. This also my first kegging and I want it to be ready to drink by March 13th for a party. When is the latest I can wait to transfer it to the keg and have it carbonate and condition properly?

Brian

IMO, March 12!

Oh really, I thought the carbonation took longer. I know it is faster then bottling but thought I had read it was a few days at least. Time to do more research.

Brian

well, it depends.  what denny was referring to is that you can keg, chill and then quick carbonate the keg by shaking or rocking the keg back and forth until no more gas enters the vessel (you can hear it rush in as you shake initially), then let it settle for about an hour and you’re good to go.

I’m not much of a fan of doing this since the bubbles are uneven and you inevitably wind up with hazy beer initially - I prefer to gas it slowly over a week or 2 as its conditioning, but I also have 10-15 kegs full at any time, so there’s usually no rush.

Of course don’t leave it in the primary until March 12th.  What yeast strain did you use?

I would say either rack it to a keg or secondary after 3 to 3 1/2 weeks.  That will give you 6 - 13 days to get it carb’d up!

I used the WLP004 Irish Ale from White Labs. I was planning on kegging around Feb 28th or so. give a couple weeks to carb and condition.

sounds perfect.

Fermentation of a typical 5 gallon batch of beer can generate as much as 50 BTU/hr during the early stages.  It is not uncommon to see 5 to 10 degF increases in temperature in very well insulated fermentors.  I have found that it contributes to “homebrewish” flavors.  The other replies in this post explain the potential off-flavors very well:  esters, fruity, hot alcohol, solvent-like, fusel alcohols, etc.  I tightly control my fermentation temperature by submerging my glass carboy in a temperature controlled water bath.  My beer has a very clean flavor profile, I can’t emphasis fermentation temp control enough if you are trying to make a high quality, professional tasting brew.

Homebrewish flavors?