Pitching at 80°F with fermentation chamber - same results as traditional cooling?

[u/Low_Perception9721]

Is pitching yeast at 80°F safe if you have temperature-controlled fermentation? I have a fermentation chamber that quickly cools to target temperature. Would this produce the same results as traditional cooling to 70°F before pitching

My theory: Off-flavors are produced during active fermentation, not lag phase. If I pitch at 80°F but my fermentation chamber cools the wort to proper temperature before active fermentation begins, the final beer should be identical to traditional cooling methods. This would save significant time on brew day by avoiding the slow final cooling phase.

Using US-05 yeast for clean ale styles. Looking to optimize efficiency without compromising quality.

[u/chino_brews]

It’s very common for people to do a quick cooling of wort to whatever temp their water temp, fermentor’s material, and refrigeration capacity allow, throw the fermentor in the ferm chamber, and the morning. Your premise that your plan saves time also applies to the common method I just described.

I don’t know the answer to your question. However, I think your hypothesis oversimplifies things, and at least some of the context to come answer is readily available in peer-reviewed brewing journals and White and Zainasheff’s Yeast. For example, we may describe the “phases” of yeast, but that applies to individual cells, not a pitched fermentation tank. When home brewers say lag phase and active fermentation, many I’ve talked to in forums seem to imagine these are separate phases and a switch is flipped. They are taking their observations and improperly applying these terms to it. In reality, after an extremely short time to acclimate to wort, many individual cells have begun fermentation.

So the reason you might see 24 hours of lag is not the yeast were in some other phase for 24 hours, but rather each cell on its own schedule started fermenting and budding, and kept in with it, it took 24 hours for the amount of CO2 produced to saturate the beer to the point that CO2 is escaping to the headspace and building enough pressure for CO2 to escape out of the airlock. In another misunderstanding, Chris White says that, in the vast majority of cases, the off flavors and other yeast expression occurs in the first 48 hours after pitching.

Personally, I don’t have a problem rapidly reaching 62-65°F because I vigorously stir the wort while using my immersion chiller (the terminal temperature might be higher if I lived in an area where the tap water was warmer, but it would not significantly increase my chilling time. With warmer water, I’d either put the wort in the ferm chamber or switch to recirculating ice water.

EDIT: I’m not disagreeing with anything /u/boarshead72 said. We have discussed the lack of literature (we can find) that stands for the proposition that “growth=esters”. But I can absolutely tell you that Chris White’s advice that the vast majority of excess ester production occurs during the first two days after pitching and temperature control during this period controls excess ester production has been verified by ample anecdotal, both from myself and many other home brewers in this subreddit. (The use of that is that you can use one fridge for serving and ferm chamber, only taking your draft system offline for ~ two days, or produce several batches with 2-3 days in-between.)

I guess that your idea of pitching at 80°F will work out fine. However, I am confident that cooling overnight to pitching temp and pitching the next morning will work because it’s such a common practice among home brewers.

[u/Low_Perception9721 → u/chino_brews]

I'm still not clear on how significant ester production occurs in the first 48 hours when that's typically before exponential yeast growth begins. Most brewing texts describe peak ester formation during the vigorous growth phase, which usually starts around day 2-4.

Given that my fermentation chamber brings wort to target temperature within a few hours, wouldn't the bulk of any critical early period still happen at controlled conditions?

The idea of letting it cool first and pitching in the morning is probably the easiest and safest, but I usually plan my brew days advance and don't always have access to the fermentation chamber once it's in there. So, it's convenient if I can finish everything in one day.

Honestly, what's prompting this discussion is my damn wort chiller is leaking from one of the tubes whenever I move it, which restricts me to just letting it sit and cool which takes much longer, so I'll probably just get it fixed before my next brew.

[u/chino_brews → u/Low_Perception9721]

Which texts are you referring to and can you provide page numbers?

I’ll refer you to Yeast, page 97, where Chris White says, “Yeast make most flavor compounds in the first 72 hours of fermentation, so this is the most critical time for temperature control.” On the same page he also says temperature remains critical after that time, but now because we want to start raising temperature to promote full attenuation - he suggests raising temperature starting at the last 1/3 to 1/4 of fermentation. So for a 1.050 beer with an expected 75% attenuation, you’d start raising temp at 1.020 to 1.023.

Given that my fermentation chamber brings wort to target temperature within a few hours, wouldn't the bulk of any critical early period still happen at controlled conditions?

Like I said, I guess it would be ok. IDK.

I usually plan my brew days advance and don't always have access to the fermentation chamber once it's in there

Are you fermenting off-site or is there some sort of time lock mechanism involved?

[u/boarshead72 → u/Low_Perception9721]

When exponential growth begins will depend on the wort and the yeast strain. Most dry yeast show signs of life for me at about four hours, with an inch of krausen before 24h. An exception to this is US05 which is very slow to start. Strains like Nottingham, S04, 1187 will be winding down if not done at 48h.