Warm versus cold fermentation

I know this happens and I guess I’m not getting why brewers do this. Why ferment for 1 week at say 68 and then 1-3 weeks at say 37.

I would think that changing the temp would just slow down the fermentation and nothing else.

Please school me !

For me it would be 65* for 2 weeks. This give the yeast the time to “clean up” after themselves.

Then turn the fridge down to help the yeast and other solid to precipitate out.

[quote=“Nighthawk”]For me it would be 65* for 2 weeks. This give the yeast the time to “clean up” after themselves.

Then turn the fridge down to help the yeast and other solid to precipitate out.[/quote]

So the cold “fermentation” is just to drop stuff out or does it change something else like taste? I read it changes clarity from the drop out.

You are talking about “lagering.”

No “ales” are feremented at 37 degrees. Ales are generally fermented somewhere in the 60’s, and that should be done for probably 2-4 weeks in general. There are different strategies that people use, for me - I just go 3 weeks in primary usually in the low 60’s - then keg or bottle. Beers also need to ferment longer than a week in general.

Now, making lagers is something else. When you make a lager - in general - you go through a primary fermentation of say 3 weeks at about 50 degrees. Then, you will “lager” the beer for an extended period of time (4-8 weeks) at temps in the 30’s to allow the beer to clear, condition, and finish up.

[quote=“Braufessor”]You are talking about “lagering.”

No “ales” are feremented at 37 degrees. Ales are generally fermented somewhere in the 60’s, and that should be done for probably 2-4 weeks in general. There are different strategies that people use, for me - I just go 3 weeks in primary usually in the low 60’s - then keg or bottle. Beers also need to ferment longer than a week in general.

Now, making lagers is something else. When you make a lager - in general - you go through a primary fermentation of say 3 weeks at about 50 degrees. Then, you will “lager” the beer for an extended period of time (4-8 weeks) at temps in the 30’s to allow the beer to clear, condition, and finish up.[/quote]

So the thread that is currently going about an Odell IPA clone where they ferment for 1 week at 67 and then 2 week at 34 means the 2 week is just for clean up and clarity? No taste difference?

I will check it out - have not read it. However, on a homebrew scale, I cannot think of any circumstance where I would ferment an IPA for 1 week and then drop it to 37. To me, that sounds like you would just be shutting down your fermentation before it actually finished. If you take an ale yeast to 37 degrees, it is not “fermenting” any more, it is going dormant. Lots of people do cold crash beer for clarity after fermentation is done to get everything to drop out of suspension. And, as beer is given a few weeks, the flavors will blend and mellow. But, again, not sure what good could come of trying to “ferment” an ale at 37 degrees after only a week. I could be missing something though. I will check out the other thread.

I think the key piece of information here is this:

“Ferments @ 67 F one week then 34 F (!?) for two weeks (according to Brooklyn Brew Shop Youtube vid interview/visit to brewery”

This is what the BREWERY does. Breweries operate in a way that maximizes profit. They do everything they can to turn their beer around as fast as absolutely possible while maintaining the quality they want. They are focused on beer 24/7 and as a result, they have processes, equipment and ability to speed every step up. It is not that homebrewers “can’t” do this - just that they generally do not have the knowledge, equipment, and need to do it. So, in the case of what the brewery does - the ferment is done in a week. The 34 degrees is simply time for the beer to “age” a little, clear, etc. Then they force carbonate it and it is ready to go. Also, an IPA is a beer that often is served fairly young because the Hop aroma and flavor is at its best and would fade over time.

My reservation was on the fact that for an average homebrewer, and average homebrewing practices, 1 week is not enough fermentation time for an ale.

Here are a couple threads that talk about this type of thing a bit - basically, big breweries ability to turn out beer fast:

http://www.homebrewtalk.com/f14/how-do- ... ndex3.html http://www.homebrewtalk.com/f13/aging-b ... ion-84005/

[quote=“Braufessor”]I think the key piece of information here is this:

“Ferments @ 67 F one week then 34 F (!?) for two weeks (according to Brooklyn Brew Shop Youtube vid interview/visit to brewery”

This is what the BREWERY does. Breweries operate in a way that maximizes profit. They do everything they can to turn their beer around as fast as absolutely possible while maintaining the quality they want. They are focused on beer 24/7 and as a result, they have processes, equipment and ability to speed every step up. It is not that homebrewers “can’t” do this - just that they generally do not have the knowledge, equipment, and need to do it. So, in the case of what the brewery does - the ferment is done in a week. The 34 degrees is simply time for the beer to “age” a little, clear, etc. Then they force carbonate it and it is ready to go. Also, an IPA is a beer that often is served fairly young because the Hop aroma and flavor is at its best and would fade over time.

My reservation was on the fact that for an average homebrewer, and average homebrewing practices, 1 week is not enough fermentation time for an ale.

Here are a couple threads that talk about this type of thing a bit - basically, big breweries ability to turn out beer fast:

http://www.homebrewtalk.com/f14/how-do- ... ndex3.html http://www.homebrewtalk.com/f13/aging-b ... ion-84005/[/quote]

Thanks.