A question on fermentation temperature

[jayjay]

Hi
I am pretty new to homebrewing so this might be quite the rookie question, but....

So far i have brewed 2 batches where i have "controlled" the fermentation temperature by regulating floor heating and reading the temperature of the room by measuring the temperature in a water bottle standing next to my fermentor and assuming that the temperature of the water in the bottle is around the same as the temperature of the fermenting beer.

However, i just learned today that the fermentation itself will generate a rise in temperature.

So is the method im currently using flawed in this regard, and will it have a negative impact on my final product?

Cheers

 

[Tobor_8thMan]

Are you brewing ale or lager?

 

[jayjay]

Ale. Always ale

 

[VikeMan]

So is the method im currently using flawed in this regard,

Yes.

and will it have a negative impact on my final product?

That depends on how warm your fermenting wort/beer is getting, what yeast strain you're using, what style you're brewing, and what your personal goals/preferences for the beer are. The important point is that if you want to control fermentation temperatures, you need to be measuring the temperature inside the fermenter and keeping that at whatever temp you want .

 

[Tobor_8thMan]

OK. What is the ambient temp where the primary fermentation is happening?

 

[jayjay]

Around 21 celsius

 

[jayjay]

Right i see your point. Any suggestion of a method that doesnt break the bank?

Yes.



That depends on how warm your fermenting wort/beer is getting, what yeast strain you're using, what style you're brewing, and what your personal goals/preferences for the beer are. The important point is that if you want to control fermentation temperatures, you need to be measuring the temperature inside the fermenter and keeping that at whatever temp you want .[/QUOTE

 

[Tobor_8thMan]

Around 21 celsius

OK, making me work here or just testing me. Around 70F. This is OK for pitching yeast, but is a bit high for fermenting an ale. Remember, fermenting adds about 10 degrees (doesn't matter C or F) to the fermentation temp. So, we're now in the 80's F (27 C). 27C is probably OK for Belgians, but for most ale, 27C is too high!

 

[Moose_MI]

Plastic tub to place the fermenter in....fill so 1/2-2/3 fermenter is under water...toss a couple ice packs in water in AM and replace with a couple before bed .... do this for first 3 days of fermentation and then just let it ride at ambient (in or out of the water bath...doesnt matter after first few days)

 

[Tobor_8thMan]

Plastic tub to place the fermenter in....fill so 1/2-2/3 fermenter is under water...toss a couple ice packs in water in AM and replace with a couple before bed .... do this for first 3 days of fermentation and then just let it ride at ambient (in or out of the water bath...doesnt matter after first few days)

Or, put in a basement where the year round temp is 58 to 62 F (14 to 17 C)

 

[VikeMan]

Right i see your point. Any suggestion of a method that doesnt break the bank?

A cheap way would be an ice water bath, but you have to really stay on top of that to maintain the temps you want A small chest freezer ($25 on Craigslist) and thermostatic temperature controller lets you walk away for hours or even days. Or you could build a "son of fermentation chiller" (google that). There are also jackets designed to wrap around your fermenter that can have ice water or glycol pumped through them, switched on and off by a temperature controller.

 

[BrewBuilder19]

I was able to build out a fermentation chamber for about $100

$35 - ink bird temp controller
$50 - Chest freezer from Craigslist
$15 - Space heater from Home Depot

I can hold temps within roughly 1-2 Degrees for weeks at a time without having to constantly check like you would with a swamp cooler. I work a pretty demanding job so I wanted something I can set and forget and that was worth spending the little extra $$$$. In terms of fermentation temps like others it depends on the style and yeast but as a general rule I like to ferment at the lower range the yeast manufacturer suggests and after 3-4 days when fermentation slows to raise temps 3-5 degrees.

 

[Moose_MI]

Fermentation chambers are great...I have a 15cu ft, 7cu ft, and a 5cu ft....yay me.

...but if you want cheap and simple for fermenting 5G of beer in a ~70F basement then get a bucket and 2 ice packs...use for first 3 days to keep your fermenting beer 66ish....done.

 

[Kharnynb]

cheap way to ferment is to buy a big cement mixing bucket(shouldn't cost more than 10-15 euro's/pounds/dollars), fill it with water and either add a few ice bottles now and again or keep the room temperature around 16 degrees celcius, the water in the bucket will act as a heat sink for your fermenter.

a (semi)accurate way to measure temperature of the beer in a simple and cheap way is to put one of those sticker thermometers on it.

 

[ncbrewer]

a (semi)accurate way to measure temperature of the beer in a simple and cheap way is to put one of those sticker thermometers on it.

Definitely worthwhile if you're using a swamp cooler. The swamp cooler drops the temperature by 2 - 3 deg F for me by evaporation. Ice bottles get it cooler if needed (depends on the season). Remember that the fermometers are water resistant - not water proof so don't submerge it.