Fermentation Temperature Adjustment?

Sundaz

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Hey everyone,
I got my Belgian strong ale going for about 6 days so far. I started at 67f temperature setting, and switched it to 68f after two days. On day 3 I had a little fermentation blow up and had to do some cleaning. Other than that, it’s been quiet lately. So I read that at some point I should increase the temperature higher. Just wondering at what point and how high?
 
TL;DR: You're probably good.

I can think of 2 reasons to raise fermentation temperature "beyond normal"

1) to perform a diacetyl rest. Generally speaking, ales are not as susceptible to diacetyl. "Diacetyl is a compound produced during fermentation, often associated with a buttery flavor in beer. It can be a byproduct of yeast metabolism, particularly when yeast is under stress or fermentation conditions are not optimal."

2) to help un-stick a stuck or stopped fermentation.

Else, if the temperature is within the yeast's "happy" range, you're probably good.

I will raise fermentation temp __within the normal range__ towards the end of the fermentation most of the time with some exceptions.

Last year I did a lager on harvested yeast, it was about 1.050 SG and on pitch #3 it tore through that beer in about 4 days. I did let it rest at a higher temp for a day, but it was already at 1.010.
 
TL;DR: You're probably good.

I can think of 2 reasons to raise fermentation temperature "beyond normal"

1) to perform a diacetyl rest. Generally speaking, ales are not as susceptible to diacetyl. "Diacetyl is a compound produced during fermentation, often associated with a buttery flavor in beer. It can be a byproduct of yeast metabolism, particularly when yeast is under stress or fermentation conditions are not optimal."

2) to help un-stick a stuck or stopped fermentation.

Else, if the temperature is within the yeast's "happy" range, you're probably good.

I will raise fermentation temp __within the normal range__ towards the end of the fermentation most of the time with some exceptions.

Last year I did a lager on harvested yeast, it was about 1.050 SG and on pitch #3 it tore through that beer in about 4 days. I did let it rest at a higher temp for a day, but it was already at 1.010.
Thanks for the info, I appreciate it. There are a lot of good information online, but I’m just trying to get the most up to date best practice. Wasn’t sure if I go by days, activity, or gravity. So I guess I’m good for now.
 
So does this mean I can go from the end of fermentation, straight to cold crashing? Sorry if this is an obvious question.
 
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So does this mean I can go from the end of fermentation, straight to cold crashing? Sorry if this is an obvious question.
This is what I usually do and even if your schedule gets delayed and you forget to raise the temp on a lager, you can still sample and more than likely not have a diacetyl problem. It's kind of like the fermentation boogeyman. It exists, but it's mostly in our heads.

I have seen where Brülosophy illustrated a gradual cold crash is superior for clarity, but TBH, I usually just drop the axe and try to make a solid 24 hours under 40F. Hopefully the mini-split will get me the extra push I need to hold mid to high 30's. I cannot afford to do several days long attempts to cold crash, my outside ambient could go from 90-100 in that time and I need to get it cold when I can and hold it there. Usually I drop the temp to the low 50's maybe high 40's the first day, and I will drop it to mid 30's overnight when it's cooler. With the mini-split I should be able to make it and hopefully keep under 40F.
 
Short answer: You don't necessarily have to but there are definitely circumstances where you may want to.

With Belgians, especially high-ABV styles ramping up temp can help finish out the fermentation. You need to check your gravity and see if it's done or stalled.

The other reason that some styles (Belgians, Hefeweizen) may like higher temps is for ester production. Since a lot of the flavor of the beer is driven by yeast-derived esters and phenols, controlling temp to help produced the right combination can be important.

A temp range of around 68F is good for most ale yeasts, including Belgian strains but you may find that you'd like more ester production and raising to 72F (or even higher) can help with that.
 
Hey everyone,
I got my Belgian strong ale going for about 6 days so far. I started at 67f temperature setting, and switched it to 68f after two days. On day 3 I had a little fermentation blow up and had to do some cleaning. Other than that, it’s been quiet lately. So I read that at some point I should increase the temperature higher. Just wondering at what point and how high?
A different(ish) take on this: once fermentation activity appears to have stopped (or nearly so) - meaning gravity is stable and little CO2 - it is good practice to let it sit for 2-4 days longer. Despite the perceived inactivity, the yeasties are still working, so let them do their thing just a bit.

That being said, once you’ve let them finish their job, a cold crash is a good thing.
 
cold crashing slowly over a couple days decreases the chance of O2 ingress thats why I do it
raise and lower in steps if you have that ability
it doesn't hurt so why not IMO
 
I ramp up my lagers for a D-rest, for ale yeast i generally leave it at a consistent temp until fermentation is complete. I will either cool it down to 60f for 24 hours if i have time OR i will crash straight from ferm temp down to as cold as i can get(2-4c). i will carb it once it hits below 6c and then let it sit for 24 hours before i package it(if i have time).

my double lager has a dryhop going on it now and it is at 80% and at 18C(also under 15psi)! sitting at 8.3%!
 
Usually with a Belgian yeast, you do want to start about 68. After a few days, you do slowly increase the temps (a degree or two a day) depending on the yeast. If a Saison yeast, you can let it get quite warm. With the regular Belgians, I would probably let them get midway up in the 70s depending on what that specific yeast likes.
Blowups are VERY common for a Belgian yeast. That is why you use a blow off tube with them. They get QUITE active.
My first time, it damn near blew the top off my Fermonster. I have not had any trouble using a tube into a growler instead of the airlock.
 
I ramp up my lagers for a D-rest, for ale yeast i generally leave it at a consistent temp until fermentation is complete. I will either cool it down to 60f for 24 hours if i have time OR i will crash straight from ferm temp down to as cold as i can get(2-4c). i will carb it once it hits below 6c and then let it sit for 24 hours before i package it(if i have time).

my double lager has a dryhop going on it now and it is at 80% and at 18C(also under 15psi)! sitting at 8.3%!

cool! So you dry hop under pressure as well?
 
cool! So you dry hop under pressure as well?
i mean i had to drop the pressure off the tank, but i did bring it back up to 15! gonna cool it tomorrow and then crash it on thursday, carb/pack it on friday. actually i have an IPA on the exact same dryhop schedule that will also get carbed/packed on friday. I need more tanks.

brewing my session ipa today and i once again hit 91% eff...dropped the lb of dextrose out of it and added a gallon of water(should probably add 2) about to start knocking it out! dryhop will go in tomorrow! ill pack/carb it on monday of next week!
 
cold crashing slowly over a couple days decreases the chance of O2 ingress thats why I do it
raise and lower in steps if you have that ability
it doesn't hurt so why not IMO
With the Allrounder and fermenting under pressure, I hit it with about 30 PSI when setting it to cold crash. Usually ends up between 10-15 PSI once down to crash temp.
 
cool! So you dry hop under pressure as well?
Whenever I do a dryhopped pale or IPA, I usually put the hop spider into the unitank as it's finishing up fermentation and close off the tank. I'll leave it for up to a week while the tank pressurizes and crashes. I find that it gives a good full-range hop flavor with a little bio-transformation, some warm dry hopping and then some extra time at cold temps. :)
 
ok, y'all convinced me.

Next time I'm dry hopping, pressure will be involved. :cool:
for a normal IPA i dont add pressure, but this was a pressure fermented lager so it felt right. plus i was trying to preserve as much carb as i could.
 
After 8 days the gravity for the delirium clone went from 1.077 to 1.030. And after 12 days it is at 1.024. I gave it a gentle stir and added a little nutrient. Do you guys think that is enough? I have an extra pack of us05 on hand I can pitch if needed to help finish fermentation.
 
I don't do ales under pressure normally but I have
I put the hops in the collection cup on my fermzilla
I keep the butterfly valve closed
when time for the hops I open the valve the pressure from the tank blows
the hops up into the fermenter
I think Ill add the hops that way to my Italian Pils when I dry hop
it will limit the O2 ingress
Ill purge the cup and hops
 
After 8 days the gravity for the delirium clone went from 1.077 to 1.030. And after 12 days it is at 1.024. I gave it a gentle stir and added a little nutrient. Do you guys think that is enough? I have an extra pack of us05 on hand I can pitch if needed to help finish fermentation.
no to the extra yeast there's plenty still in it
your not even 2 weeks yet
I'll bet it goes down more if you mashed below 150
 

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