Overly hot wort

When I was brewing last night, I forgot to check the temperature of my wort until after I added my yeast. As it turned out, the wort was between 110 and 115 degrees! I stirred the liquid german wheat beer yeast into the wort thoroughly after aerating it, if that makes a difference. This is only batch number 3, so things are not down to a science yet. Should I add another vial of yeast now, or should I give the yeast that's in there a few days first? How high of a temperature can yeast stand(at least until the wort cools)?

Thank you in advance,

Brandon

In this thread earlier today (https://www.homebrewtalk.com/f39/2nd-brew-1st-mistake-rehydrating-yeast-189253/) it was stated that:

Justibone said:

Any temperature over ~80F can kill yeast within a few minutes.

Any temperature over 150F can kill yeast in seconds.

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Hm, I guess I'd better pick up some more yeast, then. I tried to cool it down once I realized what happened, but it may have not been fast enough if it only takes a few minutes to kill yeast above 80 degrees. Thanks!

Brandonsantacruz said:

Hm, I guess I'd better pick up some more yeast, then. I tried to cool it down once I realized what happened, but it may have not been fast enough if it only takes a few minutes to kill yeast above 80 degrees. Thanks!

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80 degrees doesn't kill yeast. If you look at a pack of notty it says to rehydrate in 88-92 degree water.

I don't know what temp will kill yeast, but 110-115 probably won't. Might make some crappy tasting beer, but I would bet it'll still be beer.

I rehydrated and pitched 2x 15 gram packages of Coopers last night, then stirred it in some.When you pitch your yeast, do you usually aerate your wort and stir the yeast in? A local brew store told me that's probably why I've been getting a high final gravity (like 20), not aerating the wort. A little off topic, but while I have your attention....

Dry yeast does not need aeration, liquid does.

IIRC, Dr. Fischborn form Lallemand cited 114 as a temp that will kill yeast.

bja said:

Dry yeast does not need aeration, liquid does.

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Why wouldn't dry yeast need aeration like a liquid yeast? With sources, please!

Link to FAQ at Danstar

According to Danstar/Lallemand "...there is no need to aerate the wort but it does not harm the yeast either. During its aerobic production, dry yeast accumulates sufficient amounts of unsaturated fatty acids and sterols to produce enough biomass in the first stage of fermentation. The only reason to aerate the wort when using wet yeast is to provide the yeast with oxygen so that it can produce sterols and unsaturated fatty acids which are important parts of the cell membrane and therefore essential for biomass production."

marc06 said:

Why wouldn't dry yeast need aeration like a liquid yeast? With sources, please!

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