Raising then lowering fermentation temperature

[aarong]

I am beginning to focus on my fermentation temperatures when it comes to cleaning my beers. I have a chest freezer with a temperature controller (heat and cool). I typically pitch 2 degrees cooler then my fermentation temp(62ish). I ferment on the low end of the yeast(64ish) and then when it is finished fermenting (constant SG over a few days) I raise temp slowly to the high end of the fermentation(70ish) to clean the beer off flavors.

Should I keep it at 70 until the beer is cleared of the off flavors (right now there is some aceteldehyde, when I pull a sample from the middle there is still some yeast in suspension)? How long do I keep it there? is it until the beer is clear or when it has no off flavors?

Should I consider lowering the temp back down slowly, if so when?

Do you have any recommendations for a typically fermentation temperature schedule?

I am fermenting a Northern English Brown Ale (all grain) with West Yorkshire yeast

https://byo.com/bock/item/1983-northern-english-brown-ale-style-profile

Thanks for your time!

 

[Artifishal]

I've been told not to lower it back down, but I'm subscribing bc im very interested to hear others responses too.

 

[CA_Mouse]

The only way to drop the yeast is to cold crash it or use something like gelatin. I generally raise the temperature after the yeast has finished the vigorous portion of fermenting (usually about day 6 or 7), but usually only a few degrees higher than what it fermented at (IE: fermented at 65, warm to 68), check for final gravity on day 9 or 10, then again 24 hours later. If gravity is stable then I cold crash to mid 30's for 24-48 hours and rack to a keg. Usually there are no off flavors or yeast left in suspension.

 

[JollyregoR]

Personally I use pretty much the same method as you stated but if I want it to clear out I usually do a cold crash for at least a couple days. It makes a big difference for me especially when I want to keg soon after a big dose of dry hops.

 

[aarong]

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[aarong]

The only way to drop the yeast is to cold crash it or use something like gelatin. I generally raise the temperature after the yeast has finished the vigorous portion of fermenting (usually about day 6 or 7), but usually only a few degrees higher than what it fermented at (IE: fermented at 65, warm to 68), check for final gravity on day 9 or 10, then again 24 hours later. If gravity is stable then I cold crash to mid 30's for 24-48 hours and rack to a keg. Usually there are no off flavors or yeast left in suspension.

I will give this a try next batch. This one still has some off flavors(aceteldhyde) which might be from poor yeast nutrients(I have no zinc in my water) I'm going to use yeast nutrient next batch. I never have a problem with attenuation. Only with yeast off flavors. I'm trying to narrow it down to fix the issues. Typically its fusels or aceteldhyde, I'm thinking due to my fermentation process, temp, and, timing.

 

[CA_Mouse]

I will give this a try next batch. This one still has some off flavors(aceteldhyde) which might be from poor yeast nutrients(I have no zinc in my water) I'm going to use yeast nutrient next batch. I never have a problem with attenuation. Only with yeast off flavors. I'm trying to narrow it down to fix the issues. Typically its fusels or aceteldhyde, I'm thinking due to my fermentation process, temp, and, timing.

If you are using water that is devoid of minerals, then you may want to look at Bru'N Water and adjust your water a bit better. If you have all the information about your water, then plugging them into Martin's spreadsheet will help you. Alternately, you can always get bottled water (I would advise against getting it from the vending machines - I've used the pre-filled jugs from Lowes with great results). Primo water actually has their water chemistry on their website, as does Glacier Water.

 

[Gavin C]

I'm concerned with this batch as it still has some off flavors.... Typically my issues are with yeast off flavors (aceteldehye and excess fusels)

These suggest overly warm /unstable beer temperatures during fermentation.

I'm puzzled as I assume your not measuring ambient temperature in the chamber but controlling and measuring the beer temperature precisely.

What pitch rates are you targeting?

Here is my current fermenting ale profile and a recent lager profile as examples. (all done in primary only) Not sure this is what you're looking for but here are two profiles I use.

Ale (currently at 68F) with dry hopping in FV


Typical lager ferment

 

[aarong]

Thank you for your fermentation profile its very helpful and exactly what Im looking for! I use brewing water but I think its an issue thats not part of the calculator(zinc) I do attach the thermometer to the side of my carboy and verified temp was correct with a calibrated thermometer directly in the beer. I tend to go very low on the minerals but will try a more agressive profile (Tasty Mcdole's ).

I use mr malty for my starters on a stir plate(default settings) and use pure oxygen 60s

I might just be paranoid with this beer and just need to relax and wait it out at the "higher" 70f temp.

Just trying to fine tune my process.

Thanks!

 

[Yooper]

The only way to drop the yeast is to cold crash it or use something like gelatin. I generally raise the temperature after the yeast has finished the vigorous portion of fermenting (usually about day 6 or 7), but usually only a few degrees higher than what it fermented at (IE: fermented at 65, warm to 68), check for final gravity on day 9 or 10, then again 24 hours later. If gravity is stable then I cold crash to mid 30's for 24-48 hours and rack to a keg. Usually there are no off flavors or yeast left in suspension.

This is pretty much what I do too, but I don't cold crash before racking generally if the beer is fairly clear.

Thank you for your fermentation profile its very helpful and exactly what Im looking for! I use brewing water but I think its an issue thats not part of the calculator(zinc) I do attach the thermometer to the side of my carboy and verified temp was correct with a calibrated thermometer directly in the beer. I tend to go very low on the minerals but will try a more agressive profile (Tasty Mcdole's ).

I use mr malty for my starters on a stir plate(default settings) and use pure oxygen 60s

I might just be paranoid with this beer and just need to relax and wait it out at the "higher" 70f temp.

Just trying to fine tune my process.

Thanks!

I don't supplement with zinc, and many other brewers don't. While yeast can benefit from it, I don't see any off flavors coming from the lack of it, particularly aceteldehye and/or fusel alcohols. Typically, that is from a too-warm fermentation or incomplete fermentation and not a nutrient lack. Malt has plenty of things like magnesium, and I've never heard of not supplementing with zinc to create those flavor issues.

I really think something else is going on- but can't figure out what!

 

[aarong]

This is pretty much what I do too, but I don't cold crash before racking generally if the beer is fairly clear.



I don't supplement with zinc, and many other brewers don't. While yeast can benefit from it, I don't see any off flavors coming from the lack of it, particularly aceteldehye and/or fusel alcohols. Typically, that is from a too-warm fermentation or incomplete fermentation and not a nutrient lack. Malt has plenty of things like magnesium, and I've never heard of not supplementing with zinc to create those flavor issues.

I really think something else is going on- but can't figure out what!

I cant figure it out either (I guess that is obvious from my post!) , I pulled the zinc as being a possible issue from Chris White's book "yeast". I am just hoping its as simple as that. I'm very happy with my tap water as all the numbers are almost identical to Distilled Water.

If it helps this was my target profile from this batch(maybe its the magnesium):
CA:80
Mg:0
Sodium:5
Sulfate:92
Chloride: 72
Bicarbonate:21

 

[Yooper]

I cant figure it out either (I guess that is obvious from my post!) , I pulled the zinc as being a possible issue from Chris White's book "yeast". I am just hoping its as simple as that. I'm very happy with my tap water as all the numbers are almost identical to Distilled Water.

If it helps this was my target profile from this batch(maybe its the magnesium):
CA:80
Mg:0
Sodium:5
Sulfate:92
Chloride: 72
Bicarbonate:21

Malt has plenty of magnesium- no need to supplement that.

Those numbers look good. What was the mash pH? Maybe it's that simple?

 

[aarong]

Malt has plenty of magnesium- no need to supplement that.

Those numbers look good. What was the mash pH? Maybe it's that simple?

Dang it! Hoping we found the issue with the magnesium

PH 5.3-5.4, I use a calibrated Milwaukee PH meter 15 minutes into mash(typically spot on with bru'n water)

 

[Yooper]

I'd be cautious about using "yeast nutrient". A guy sent me beers over and over trying to nail down an off-flavor, and we went through EVERYTHING. Finally, in one PM he mentioned "yeast nutrient", which apparently is DAP. I told him to try again, and leave it out- and his beer is fixed!!!! Completely fixed. Some of the earlier issues were mash sparge pH and things- but the DAP created a whole new off-flavor. So I would read up, and consider what to supplement, but not use "yeast nutrient" that meadmakers use.

One last thing- is what you're tasting maybe a character of the West Yorkshire yeast? It's got some weird esters, especially at higher fermentation temperatures.

 

[aarong]

I'd be cautious about using "yeast nutrient". A guy sent me beers over and over trying to nail down an off-flavor, and we went through EVERYTHING. Finally, in one PM he mentioned "yeast nutrient", which apparently is DAP. I told him to try again, and leave it out- and his beer is fixed!!!! Completely fixed. Some of the earlier issues were mash sparge pH and things- but the DAP created a whole new off-flavor. So I would read up, and consider what to supplement, but not use "yeast nutrient" that meadmakers use.

One last thing- is what you're tasting maybe a character of the West Yorkshire yeast? It's got some weird esters, especially at higher fermentation temperatures.

Know what, I bet you are right! I should of searched for that yeast earlier as its the first time I used it in an English ale. I could be confusing aceteldhyde with the tart aroma this yeast puts out. (not my favorite I will probably switch strains)

I just purchased wyeast nutrient and will research it some more/look elsewhere to solve my off flavors before using it.

 

[CA_Mouse]

As far as yeast nutrient, I only use it for meads and starters. I've never used it in any beer or cider. I'm thinking that the yeast may have been the issue, I've never used that particular strain myself.

I agree with Yooper about DAP, that can cause some temperamental yeast strains to do some funky things.

 

[aarong]

Quick update the aroma. Which seems like aceteldhyde went from about a 7 to a 2 over the last few days. I used to open the fermenter and get an overwhelming aroma. Now its a faint smell and when in the glass its barely noticeable. I did not change temp or adjusted anything. I will keep it on the yeast until its cleaned up. Then crash and keg. I guess the relax don't worry thing works. I'm looking forward to trying the advice given on my next batch.