Temp Fluctuation vs Higher Brewing Temp

[aurelius121ad]

I am guessing this is probably one of those questions with no definite answer ("to rack or not to rack?" and "bulk prime or bottle prime?" come to mind) but I thought I would ask for some opinions anyway. I know 16-18* is optimal for ales but a consistent temp is also important.

So whats better for the brew: a consistent brewing temp of 24* or one that fluctuates from 18-24* from the addition of ice into the water bath the fermenter sits in?

My set up consists of my fermenter sitting in a huge tub with roughly 80 liters of water. This water bath is what I measure temperature from, I assume the 80L bath would be the same as the 17L of brew in the fermenter. Adding bottles of ice to the bath two to three times a day seems to give me a fluctuation of 18-24*.

My freezer is small and I do work and sleep so changing the ice out more frequently to keep the temp down just isnt possible. That fluctuation seems to be the best I can do. I realize that 18-24* produces a drinkable beer (all my brews have been drinkable) but like most everyone else I am always looking for ways to improve.

[homebrewer79]

From what I've read it would be better to have a constant 24, due to the yeast getting stressed from temp fluctuating. In summer my brews dont drop below 22 and they still turn out very nice, and before I knew about the correct temps to brew at I kept them at 26 and they were still good.

[Chris]

Pretty much. I'd go for consistant over lower- obviously still striving for lower temps. Maybe you could aim for a constant 22*C?

And rack. Bulk prime too.

[warra48]

I agree, but there are limits to constant. I wouldn't go over 22 to 23ºC for ales.
Who would want to drink a brew fermented at a constant 29ºC ?

[Chris]

Constant 29*C versus a brew that gets to that temp daily? About the same really.

[Kevnlis]

The idea behind holding a certain temp is that the yeast are more able to clean up after themselves. If you have yeast that are going from 18-24 and back every day it will not spend enough time at any one temperature to remove the volatiles it has produced. This means the yeast profile of the beer will be severly unbalanced in most cases. Every yeast is different though and some yeasts like Coopers famous strain are able to cope with this sort of stress much better than others. There are also styles which would benefit from the over production of some of these components (like some wheat and belgian beers).

It is otherwise always better to try to hold a temperature that is higher than you would like, than to have large variations!

[drsmurto]

I've been told you can get away with US05 at 22C

I tend to brew my English beers at 20C to get maximum ester production but will also leave them in primary to give them time to catch up on some housework.

Of course, if 24 is the regular temp in your house them maybe you should try these yeasts - Link 1, Link 2, Link 3, Link 4 and of course as kev mentioned, the belgian yeasts......

[gregb]

I have gotten away with US05 at 22C. An APA with so much crystal malt and cascade hops that the poor esters just never stood a chance.

Cheers,
Greg

[aurelius121ad]

Thanks for the help. Looks like there is a definite answer after all to this one. It also makes it easy on me not having to change out ice 3x a day!

The temp in my house is anywhere from 26* to 35* or so in the summer but the tub of water my brew sits in remains pretty constant at 24* with no ice additions. For now thats the best constant temp I can hold. It should be easier to get down to around 16-18** during the winter when the ambient temp inside my house is around 20*. I guess that means I should brew like mad during the winter and take the summer months off!