DMS and Contamination from slow cool. How real is the risk?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

CyberErik

Well-Known Member
Joined
Jun 8, 2012
Messages
54
Reaction score
1
Location
Philadelphia
Hey guys,

I tried something new today when I pitched a batch and it backfired.

Normally, I finish the boil then cool the whole pot over several minutes or hours in an ice bath to ~78 degrees before pitching.

Today's recipe called for boiling a concentrated batch, then flash cooling to around 150 degrees, then adding this half batch to a half batch of cooled water already in my fermenter.

I did this, but instead of going down to my 75-80 degree target, it just sat at ~88-90 degrees for over an hour. I wrapped it in ice packs, I put it outside (covered) on a cold night, it wouldn't budge.

Finally I threw the whole bucket into a swamp cooler in the bath tub. It is now around target at 81 and I am about to pitch. But it sat at 85-90 for well over an hour.

My question is, how real then is the risk of DMS or contaminants growing because of a cool that slow?

My impression is the risk is pretty low, but I'd like some opinions.
 
I'll defer to the more experienced brewers, but I would agree that the risk is very low, especially if you were careful about sanitation
 
Dimethyl sulfide (DMS)

I pretty much exclusively let mine cool on the back deck. I have a batch setting out in 40 degree weather right now.

I will pitch my re-hydrated yeast in the morning.

I did an ice bath once. It seemed messy and wasteful.

https://www.homebrewtalk.com/f128/dms-where-does-140f-come-132559/

I'll have to think about it.

In the eighty degree range. I think you're out of trouble.
 
Judging by that link you posted- it's only over 150 that it's a huge problem. The problem at 80-90 is contaminants. Hopefully I avoided that- I sanitized well.

Thanks!
 
DMS is a very low concern with a slow cooling. Most is driven off during the boil.

81 degrees is very high. I cool to at least the mid 70's before pitching and preferably the mid 60's. It usually takes at least 20 minutes and mid summer it takes up to an hour to chill the wort. I have also cooled overnight and pitched in the morning with no ill effects.
 
DMS is a very low concern with a slow cooling. Most is driven off during the boil.

81 degrees is very high. I cool to at least the mid 70's before pitching and preferably the mid 60's. It usually takes at least 20 minutes and mid summer it takes up to an hour to chill the wort. I have also cooled overnight and pitched in the morning with no ill effects.

Yes, thanks for the clarification.

I did not mean to pitch now, just that it wouldn't hurt the wort to be there. 81 probably wouldn't be the worst, bu lower would be better.

Mine will be about 45 in the morning - maybe lower.
 
fermentation started ~3 hours after pitching, and is going furiously. I have it rigged with a blowoff tube.

thermometer resting on top of the bucket reads 71 degrees.
 
Back
Top