Yeast with lowest temp tolerance

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Falstaff

A Bad Influence
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What is the DRY yeast with the lowest temperature tolerance for fermentation?

I did an experiment on my fridge, and on it's lowest setting it holds temp at 45f.

I was sure it would be higher, and I can't afford a temp controller for another week, but I want to brew this weekend.
 
What temp are you looking for?I'm not understanding your question. 45 is already lower than you want to ferment. Most lager yeasts want 50 to 52. Ales are good at 62 to 65, in general. Why is 45 not low enough? It's not low enough to cold crash, but fhat comes after fermentation.
 
I'll confess, I don't know which dry strain can handle the coldest cold best, but I would guess it *might* be along the lines of Diamond or S-189 or W-34/70. Maybe split a batch 3 ways and try them all and see what happens.
 
What temp are you looking for?I'm not understanding your question. 45 is already lower than you want to ferment. Most lager yeasts want 50 to 52. Ales are good at 62 to 65, in general. Why is 45 not low enough? It's not low enough to cold crash, but fhat comes after fermentation.
I phrased it weird, I guess. What I meant was could any yeasts tolerate fermenting at 45f because that is as warm as I can get my fridge.
 
I did an experiment on my fridge, and on it's lowest setting it holds temp at 45f.


what about it's highest setting?

and i can't think of it, i've seen some lager yeast that can ferment at 48f, i'll look...well, looks like they all do..

it'd probably be a 3 week ferment, but should eventually be done? not sure on that, but report back if you try!
 
Personally, if it was a choice between maintaining the fermentation temperature I wanted (but had to wait a week for a controller) or fermenting without a controller, I'd wait.

That said, believe it or not, traditional cold lager fermentation is/was in the mid 40s. My only concern would be with rehydration of dry yeast in the wort if using the sprinkling method. It might be wise to do a proper rehydration at a higher temp, then gradually decrease the yeast slurry temp down to a temp close to the pitching temp.
 
Mid 40s really isn't a huge issue for many lager strains because fermentation gives off heat. The beer will be a few degrees warmer during fermentation than wherever the thermometer is in the fridge. It's not ideal but probably not fatal, either.
 
8C/45F is my standard temperature for fermenting Fermentis W34/70 and Fermentis S-189.
Fermentis S-23 prefers a bit higher temp of 12C/53F, but still doesn't stall out at 8C/45F. It just doesn't produce its unique subtle flavour profile when fermented too cold.
At such as low temperature, I keep my Lagers in primary for longer, like for 3 weeks.
 
8C/45F is my standard temperature for fermenting Fermentis W34/70 and Fermentis S-189.
Fermentis S-23 prefers a bit higher temp of 12C/53F, but still doesn't stall out at 8C/45F. It just doesn't produce its unique subtle flavour profile when fermented too cold.
At such as low temperature, I keep my Lagers in primary for longer, like for 3 weeks.
Yeah I was gonna use 189. Seems to be the lowest temperature tolerant yeast. I was hoping somebody would see something I missed, but this may have to do!

Or I'll follow other recommendations and wait a week 🤔
 
Lots of yeast strains are active at low temperatures, but activity is going to be suboptimal. Why promote that? Unless you live in a hut somewhere in the Arctic and winter's coming, why waste time and energy maintaining suboptimal conditions? It's a bit like the other end of that fairytale about stunningly destitute traditional kveik brewers maintaining fermentation temps close to 40°C. 'Pull the other one', that is. AKA 'my arse'.
 
Lots of yeast strains are active at low temperatures, but activity is going to be suboptimal. Why promote that? Unless you live in a hut somewhere in the Arctic and winter's coming, why waste time and energy maintaining suboptimal conditions? It's a bit like the other end of that fairytale about stunningly destitute traditional kveik brewers maintaining fermentation temps close to 40°C. 'Pull the other one', that is. AKA 'my arse'.
Yeah I'm probably just gonna wait till payday. I was really hoping that the mini fridge would hold at 50. Oh well.

My next experiment is to see if it can hold proper lagering temps at max power.

Fun experiment, too, because I put a beer in the fridge to measure the temp, which I promptly drink!
 
Mid 40s really isn't a huge issue for many lager strains because fermentation gives off heat. The beer will be a few degrees warmer during fermentation than wherever the thermometer is in the fridge. It's not ideal but probably not fatal, either.
I had wondered about this. I was worried lager fermentation wouldn't be vigerous enough to generate enough heat.
 
I've run S-189 and 34/70 below 50F, they sort of still keep going, but slow. If you're going to run it that cold, the importance of a D rest and letting it generally clean out at a temp above 60F for a week or more near end of fermentation becomes more important. For really good beer, anyway..

One reason to run very cold is if one would want to leave a brew in cold cellar and not have to deal with for a while. That is cool, and if you're going to leave it in a 45F degree cave for the winter, ...well I'd love to taste it...but I digress..

There is some view that if cold fermented is good, colder is better, that only works out to a point.

I've messed around with this, and in my opinion, my lagers come out best when fermented at to low to middle end of reccomended temps for yeast. I think 189 & 34/70 optimal temp on directions is roughly around 52-59F, and that seems to work pretty well. Though I've certainly made some good beer fermenting a little warmer.
 
I had wondered about this. I was worried lager fermentation wouldn't be vigerous enough to generate enough heat.
wrap it in a blanket or beach towel.

and pick a lager yeast that is not known for sulfur, at those temps it'll take quite a while to clean up.

and i'd say minimum 2 packs of yeast. hell, i'd even do a starter to build up yeast counts beyond that. at such low temps, you want a heavy yeast pitch. it'll get you a super clean ferment despite the low temps.
 
Pick up a solenoid driven temperature controller like InkBird' ITC-308 and plug your refrigerator into that. The temperature probe goes into a thermal well so you're controlling the wort temperature instead of the fridge temperature. You want the fridge control on maximum cooling and you can put something inside to warm it as well. The controller will hold you plus or minus a few degrees at any temperature you need within the range of the fridge and heater.
 
Here’s an interesting chart I found online. Don’t take it as the Gospel, just interesting for comparisons…
73844457-4A47-45AC-8EC9-B8E80E123AE2.jpeg
 
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