Is 47 degrees too cold for fermentation to start?

Hey guys,

My second day here at the forums, and the second thread.

Okay, I decided to go back making smaller batches for various reasons. One of them being that I've got a small fridge I'd love to use for controlling fermentation temps and do some lagering.

I did some measuring, and the coldest it gets is around 28, and warmest around 47.
I wish I could get it up to 50, but this is what I've got.

I believe 47 is good when the fermentation is active as it generates heat. I'm worried that if I pitch my yeast to around 50, and put it in the fridge, will it start at all? Can lager yeast start fermenting that low? Any experiences, am I good to go?

I'm planning to use either Saflager W-34/70 or Mangrove bavarian lager m76 (both dry yeasts).

Thank you very much again for your help!

 

The Fermentis specs. sheet: http://www.fermentis.com/wp-content/uploads/2015/12/Saflager-W-3470-en.pdf

So I think it would be too cold, given that he ideal temp. starts at around 53F.

Maybe you can try to warm up the fermenter with a ferm. belt or cover it with some insulation/warm clothes?

 

Its just a small batch, go ahead and try it. You might have to give it more time, but eventually it will get going.

 

I think it’ll go. But here’s a couple ideas. For the warmer temps, unplug the fridge. Freeze some soda bottles filled with water to get those higher temps, but try to stay in low 60s. A brew belt (heater), and temp controller would be ideal for your setup.

 

Okay, thanks, guys. I think I might try M76 yeast as it should work as low as 47. And once the fermentation starts I'm sure it will heat up a little more. Who knows, this could be almost perfect temp for it!

For ale beers, I think using frozen soda bottles could work quite well! Though, from what I've read, I think W34/70 performs well in higher temps as well. So might try doing it like that if I'm not happy with the M76.

Alright then, I'll try mashing next week, fingers crossed.
And meanwhile, I'd welcome more opinions from seasoned brewers!

 

I lager with 34/70 all the time but usually @52* Never tried it any cooler than that. It might be OK at your temp if you gave it some oxygen and a strong yeast pitch. IDK.

 

How about put your beer in the fridge with the temperature set kinda high (40's), and pitch it when it gets to 50-something degrees? You can take it out of the fridge until you see some signs of activity, then put it back. It shouldn't be that hard to work with. If you overshoot and get it too cold, just take it out for a while. The temperature doesn't change that fast.

 

Temp controllers are pretty cheap.

 

I think 47 might be a little to cold. You can try warming up the fermenter. A trick that works for me is to take a shirt or towl & throw it in the dryer for a little bit. Then wrap it around the fermenter. It usually helps.

 

I pitch my lagers at 43 and ferment at 48. You're good as long as you used enough yeast. If doing a warm-ferment (50f +) then you don't need as much yeast as a cold ferment.

 

Why not get a temp controller and a carboy cap with a thermal well? Then the fridge will only run until it gets down to whatever temp you set it at.

 

Thanks for all the answers!

Huh, interesting. I'm doing around 7,5l batch (around 2 gallons), you think one packet of rehydrated W34/70 would be enough? Might be a tiny bit under-pitching, but I think I'll give it a go. Though, still not sure if I use W34 or M76.

Also, I'll take a look at those temp controllers, probably could find something affordable!

 

I think you should be ok. I've used 3pks of 3470 into 14L of doppelbock and it worked fine. and two packs into straight OG lager.

 

Inkbird sells great controllers for about $35. Then, if you know your way around a refrigerator, you can add a ceramic reptile heater for your heat source. Then, what I did with my kegerator, is bypassed the factory installed thermostat (removed it completely) and plugged the kegerator directly into the Inkbird along with the plug from the ceramic heater. Now you can control temperature from your lowest possible all the way up to mid 70’s all for under $50.

Good Luck!

 

I recently put a 5 gallons of Red lager in my keezer at 43F. Didn't feels like changing the temp. It was probably fermenting at 45F. 36 hours later it was bubbling.

 

I have done lagers at 50 degrees. So 47 is low but I don't think so low that it wouldn't ferment.

I also suggest a temperature controller. An Inkbird works very well and is not very expensive.