Testing "Pitching too Hot"

[Onkel_Udo]

So I have accidentally done a little test of the concept that pitching to warm will produce off flavors. I realize it actually fermenting to warm that causes the issue but in my case...it is the same thing almost. Let me 'xplain. No, there is too much. Let me sum up (bonus if you get the reference).

My brewing thermometer is only accurate between 130f and 170f. I tend to verify wort fully chilled with my lab thermometer which take forever to stabilize.

One beer I drained on top of the dregs of an S-04 for my RyePA. Lab thermometer showed 70f but I only took one reading because I was bit toasty. Temp probe when I put in the fermentation chamber was 78f and at 10 gallons it can only drop about 1 degree an hour without active fermentation. So overpitch and over warm.

Same basic story on my Mangrove Jack's Newcastle Dark yeast and a dark mild...variation on theme.

So to this point, no fussels or off flavors so my query is...are these negative effects that I HAVE had before in my early days of brewing more an issue during the reproduction phase maybe? Did I just get lucky?

Keep in mind, neither beer got to my optimal pitching temp of 64 until about 18 hours later. These are also very low alcohol beers.

 

[billl]

There seem to be very few absolutes in brewing. Pretty much everything depends on a whole host of variables.

There really is no doubt that overly stressed yeast produce off flavors. Pitching too warm is a stress. Underpitching is a stress. Not enough O2 is a stress. Poor nutrients are a stress. High ABV is a stress etc, etc, etc. Lots of times you can get away with 1 misstep. When you start having multiple stresses, they seem to compound each other.

Presumably, you've learn a bit since you first started and your overall process is better. That will give you some leeway for these type of mistakes.

In this particular case, your mistakes probably offset each other a bit. Most off flavors from heat come during the main reproductive phase. Since you overpitched, the yeast didn't have to divide as much as usual - especially in a low ABV beer.

 

[JohnSand]

Let me 'xplain. No, there is too much. Let me sum up (bonus if you get the reference).

"He's been mostly dead all day" "If we only had a wheelbarrow.."

I often pitch a little warm and cool after. Mostly in warm weather when it is harder to chill. No trouble with US-05 or Westmalle. I agree that you can stretch one limit while fermenting.

 

[Onkel_Udo]

In this particular case, your mistakes probably offset each other a bit. Most off flavors from heat come during the main reproductive phase. Since you overpitched, the yeast didn't have to divide as much as usual - especially in a low ABV beer.

I was specifically fishing for the information about the off flavors coming (primarily) from the reproductive stage. It had been hinted at in other discussions and it seems to make sense.

My level of overpitch is a common practice when I do low alcohol beers. When I am in the "high production" mode to stock up for a race or something, I do back-to-back beers that share a common yeast with the first beer's dregs allowing complete fermentation in 2-3 days...kegged in a week. To protect against potential negatives of the practice I have always started at the lowest end of the viable spectrum for the yeast and ramp up each day to the mid-point then two days at 75 f finally crashing to 34 f.

I do not recommend it in general but it has proved very effective. Now I know that I probably have some leeway for errors...but that is a slippery slope.

 

[ThunderKhajiit]

What I wouldn't give for a holocaust cloak.
I almost always pitch too warm ~80 degrees. By morning it is down to 65ish. My beers are all award winners. j/k, but i've never had nasty off flavors but usually worry about it because pitching too warm. It's just a little ritual I go through.

 

[Onkel_Udo]

Thanks for all the advice guys...and congrat's to those that go the reference. I will leave you with this:

"Good night, Westley. Good work. Sleep well. I'll most likely kill you in the morning."