Fermenting a tad too cold??...

[ballsy]

Wanted to use this as an FYI type post for the other new brewers out there who are swamp cooling and also as an easing of my mind. Prior to swamp cooling I always read here that ferment temps are anywhere from 5 up to 10deg warmer than the ambient air...I took that as a general "ambient warmer than ferment" rule. So when I switched to swamp cooler, I figured I'll keep the water temp at 60deg b/c that means ferment temp is actually mid to upper 60's...well, turns out through this board, bucket in water does not allow as much of a temperature variation vs ferment temp...apparently it's only about 1-2 deg warmer (provided it is in sufficient amt of water). I think I've been fermenting on the wee cold side, and the two beers I currently have in primary did not attenuate fully b/c of this. A Belgian Tripel (double pitched T58, 1.083 OG) is on 4.5 wk mark and OG stuck at 1.023 (and cloudy). Gave her a gentle stir tonight and there was airlock activity within minutes...could be CO2 coming out of solution, but hopefully the lil guys wake up enough to eat up a little more sugar...will definitely need to cold crash this one prior to bottle.

 

[blackflagbrew]

Water is a much better conductor of heat than air and will definitely keep your ferment cooler than just a carboy on the basement floor. That said, usually fermenting on the cooler side is recommended to keep off-flavours to a minimum. To lower your FG, rouse the yeast and move to a warmer place of the house to allow them to fully attenuate.

 

[ballsy]

Water is a much better conductor of heat than air and will definitely keep your ferment cooler than just a carboy on the basement floor. That said, usually fermenting on the cooler side is recommended to keep off-flavours to a minimum. To lower your FG, rouse the yeast and move to a warmer place of the house to allow them to fully attenuate.

I typically take them out of water and let sit at 72 room air after 5 days or so. But this Belgian Tripel didn't care b/c after I gave it a gentle stir last night, the airlock has been bubbling away and continues to now. I know some people "swirl" their bucket every few days after the Krausen falls in order to keep the yeast from going to sleep and have better attenuation. I guess I may start doing this...

 

[DoWBrewer]

For beers that have sugar additions, I ferment fairly cool and then boil water with yeast nutrient + sugar. I add this about 3 days into the fermentation and then let it free rise. It does a good job of waking the yeast up just in time for the temp rise. I have used it on stuck fermentations too and it seems to work well.

 

[ballsy]

For beers that have sugar additions, I ferment fairly cool and then boil water with yeast nutrient + sugar. I add this about 3 days into the fermentation and then let it free rise. It does a good job of waking the yeast up just in time for the temp rise. I have used it on stuck fermentations too and it seems to work well.

Yeah, it seems the sugar/candi syrup addition to ferment bucket after few days is pretty standard for Tripels...but the kit I did said to add sugar during the boil so I did at end of boil. Not really sure what the difference is b/w the two techniques taste wise?

 

[DoWBrewer]

Yeah, it seems the sugar/candi syrup addition to ferment bucket after few days is pretty standard for Tripels...but the kit I did said to add sugar during the boil so I did at end of boil. Not really sure what the difference is b/w the two techniques taste wise?

The real difference is that the yeast will ferment the simple sugar first and then maltose (and other complex sugars). This causes some self-selection of yeast since yeast have to prepare to eat the more complex sugars. By putting the sugar in later, they have already done their work to eat the complex malt derived sugars. By that time you add the simple sugar, the yeast are starting to slow down, but they will wake right up to eat the simple sugar and finish at a lower final gravity (generally, there are a lot of variable in brewing). For high gravity beers, the additional yeast nutrient is just to keep the yeast healthy. I am not sure what the real impact is on the yeast.

 

[ballsy]

The real difference is that the yeast will ferment the simple sugar first and then maltose (and other complex sugars). This causes some self-selection of yeast since yeast have to prepare to eat the more complex sugars. By putting the sugar in later, they have already done their work to eat the complex malt derived sugars. By that time you add the simple sugar, the yeast are starting to slow down, but they will wake right up to eat the simple sugar and finish at a lower final gravity (generally, there are a lot of variable in brewing). For high gravity beers, the additional yeast nutrient is just to keep the yeast healthy. I am not sure what the real impact is on the yeast.

That may have been my problem...after 4 wks in primary, SG was 1.023...I gently stirred up bottom and got activity about 5 d's ago, checked today and got down to 1.020...not happy with this. Will recheck in 3 d's but thinking this may be its final resting point...

 

[ballsy]

Actually, correct that. I think 1.020 is pretty standard FG for T58 looking at other threads so not going to stress it...1.083 to 1.020 is good enough.