Is my yeast dead?

BeerBelly · 09-27-2009, 10:08 PM

I bought White Label liquid yeast on Friday. I forgot to put it in the fridge and when i began brewing on Sunday I then realized this mistake. The yeast was left out at around 75 degrees. Is my yeast dead? If I go ahead with the wort and pitch the yeast after cool down will my batch be ruined if the yeast is in fact dead? What should I do?

FishinDave07 · 09-28-2009, 02:39 AM

pitch as you would normally. If it doesnt ferment, no biggie, just get more yeast. A starter would really help though.

**Revvy** · 09-28-2009, 02:55 AM

It's really doubtful anything happend to the yeast, someone said today that they can survive in temps up to 120 degrees f. So I am sure yours is fine.

But you should make a starter to ease your mind, and give it time for any of the still viable cells to reproduce...It doesn't take many cells to do so...It just takes time.

That's why we can grow a huge starter from the dregs of a bottle of certain commercial beers....we just left the viable cells reproduce.

I made a detailed posting of why you should make a starter with liquid yeast all the time, here, http://www.homebrewtalk.com/f39/starter-pitch-packet-138810/#post1573882

Even if there's a few cells alive it they will most likely take off.....they just have to fool around and make more babies first.

Take a read of this http://www.homebrewtalk.com/f163/am-i-cursed-dead-white-labs-again-135785/#post1553441

I tend to think that most of the people who think their yeast died, just didn't wait long enough to know for sure...

And remember, http://www.homebrewtalk.com/f39/fermentation-can-take-24-72-hrs-show-visible-signs-43635/

If you do just pitch, though I wouldn't, don't do anything til it's been 72 hours...then check to see if a krauzen formed, and/or take a hydrometer reading...if there's not been a drop then more than likely all the yeast was baked...but like I said in that post I linked you to, yeast are very hardy friking creatures....they can survive in amber through some pretty harsh temp conditions and still make beer with.

BeerBelly · 09-28-2009, 02:51 PM

Thanks for the response! Sure helps to have kind people help out the rookies!

I asked my homebrew shop if I should pitch the yeast and 'wait and see' but he said NO because if the yeast WAS dead it would ruin my batch, is that true?

**Revvy** · 09-28-2009, 02:56 PM

Quote:

Originally Posted by BeerBelly

Thanks for the response! Sure helps to have kind people help out the rookies!

I asked my homebrew shop if I should pitch the yeast and 'wait and see' but he said NO because if the yeast WAS dead it would ruin my batch, is that true?

NO it's not true....if you have dead yeast and you pitch fresh yeast the living yeasts will eat it as well as the wort. A lot of us add yeast in the boil to kill it and use it as yeast energizers/nutrients. Or buy "brewer's yeast" from the health food store or even bread yeast and do the same thing.

And like I have linked you to, it is very doubtful you have totally dead yeast.