High Temp Pitch Oopsy

[BrewHack]

Tired, distractions... ect. I miss read my floating thermometer. Thought it was 25C, really was 35C. I transferred to my carboy and pitched US-05. Didn't realize what I had done until I moved the carboy to the fermentation chamber and inserted the temp probe into the thermowell. I've been cooling it with ice packs and a fan. Dropped 10 degrees in 2 hours.

So I figure I'll know if the yeast is dead by tomorrow. I'm familiar with the recipe and expect bubbles in 12 hours. If there is no activity I'm thinking about pitching again. What do you guys think?

 

[day_trippr]

It's a crap shoot. 35°C is 5°C above Fermentis' recommended hydration temperature range and is 11°C over their recommended fermentation range.
I'd be inclined to have enough yeast on hand for a repitch if there's nothing evidently happening after 48 hours...

Cheers!

 

[MaxStout]

If the yeast was killed by the 35C wort the upside is that it probably didn't live long enough to produce off-flavors.
Pitch another packet if nothing happens in a day or so.

 

[BrewHack]

Thanks!

 

[monkeymath]

I honestly cannot imagine yeast would die at this temperature.

 

[Toxxyc]

Yeast definitely didn't die. I'd pitch an additional packet ASAP anyway just to prevent the unhappy cells from producing too many off-flavours during the fermentation though.

 

[BrewHack]

Yeast definitely didn't die. I'd pitch an additional packet ASAP anyway just to prevent the unhappy cells from producing too many off-flavours during the fermentation though.

P+15hrs,:
- pretty weak bubbling
- thin krausen

Pretty underwhelming. Defiantly under pitched. Adding another pack could overpitch... so which is worst?

 

[MaxStout]

If the first packet is slow, adding a second packet wouldn't really be overpitching. Leaving it as-is would be worst, and the sluggish yeast might produce off-flavors.

 

[day_trippr]

US-05 isn't exactly known for fast and burly starts - indeed it gets lots of complaints about slow starts - so the pitch may be OK.
That why I specified 48 hours...

Cheers!

 

[BrewHack]

US-05 isn't exactly known for fast and burly starts - indeed it gets lots of complaints about slow starts - so the pitch may be OK.
That why I specified 48 hours...

Cheers!

You were right.
I checked the fermenter again and it has steady bubbles and a good looking Krausen growing. Smells great too. I think I got lucky. Going to let it ride.

 

[IslandLizard]

[...] really was 35C. I transferred to my carboy and pitched US-05.

By that time it may have lost another 5-10°C...

It's a crap shoot. 35°C is 5°C above Fermentis' recommended hydration temperature range [...]

In that light of the above ^^, I wouldn't worry about it at all.

Was the pitched yeast sprinkled, or rehydrated when pitching?

 

[BrewnWKopperKat]

US-05 slower start? Fermentis "Tips & Tricks" (pdf, direct link, also here), p 28 may be of interest.

 

[day_trippr]

By that time it may have lost another 5-10°C...[...]

Didn't realize what I had done until I moved the carboy to the fermentation chamber and inserted the temp probe into the thermowell.

I take that to mean the "35°C" was measured post-pitch, so a true 35°C bath for the yeasties

Cheers!

 

[BrewHack]

Yep, yeasties were hydrated and pitched at 35C. Then cooled to 18C with in 4 hours. Tough little buggers.

 

[IslandLizard]

Yep, yeasties were hydrated and pitched at 35C

A bit hot, but 50/50, IMO.
Wait and see...

 

[Toxxyc]

P+15hrs,:
- pretty weak bubbling
- thin krausen

Pretty underwhelming. Defiantly under pitched. Adding another pack could overpitch... so which is worst?

Underpitch is WAY worse. Overpitching, practically speaking, is very difficult in homebrewing. There have been tests done where people pitch 10 times the required amount of yeast and the only effect was a very fast fermentation and slightly lower esters due to the lower amount of yeast growth.

If you give me the option of over vs underpitching with regular dry yeast, I'll pick overpitching 10/10 times.

 

[BrewHack]

I tasted this beer yesterday and can report it's delicious. Had good attenuation too. No ill effects from accidentally pitching at 35degC.