Old Yeast still viable?

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Goyagon

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I have a 1L mason jar of yeast the was used in an ipa 3 months ago. I heard that if the yeast is a peanut butter color it is unusable. Mine looks like peanut butter but not as dark but definately darker than before. it also smells very strongly of hops and stink. Is it still viable? Will restarting the yeast work?

I pitched some into the wort after i got it to room temp but theres 0 activity with an og of only 1.040.
 
A simple starter would have told you if it's still viable or not. IMO/IME, a few months should be ok. Provided it was kept at the right temperatures. How long ago did you pitch the slurry? Without knowing the cell concentration, and how much you pitched, it's virtually impossible to say if you pitched enough, or far too little. Give it the normal 72 hours before you start looking to get newer yeast.
 
Give it a day or so on the test wort and see. If it is starting much more slowly than the strain usually starts, that's not a good sign. It'll probably still work, but it indicates that the yeast is not behaving like it did before. It's likely it will perform differently in other ways as well.

If it never starts, then obviously it's shot. Some suggest that a small quantity of lower gravity wort (~1.020) can be a better way to awaken a sluggish sample.

If the yeast smells *bad*, then I would probably discard it on that basis alone. I have a starter going from some yeast I rinsed and harvested in November (almost 2 months ago) and it smelled pretty much like fresh yeast. It took off in a half-liter of 1.020 wort, and then chewed through 2.5 liters of 1.040 wort in less than a day with vigor, odor, and appearance that were very similar to a pitch with fresher yeast from the same generation. That's what you want to see.

If you're unsure, ask yourself whether it's worth risking a batch of beer on this yeast.
 
Without knowing the cell concentration, and how much you pitched, it's virtually impossible to say if you pitched enough, or far too little. Give it the normal 72 hours before you start looking to get newer yeast.

Good point---assuming the pitch rate is similar to before, I would use the known usual lag time as a benchmark. If that has changed greatly, something ain't right. As long as it starts, it'll still make beer... but so will bread yeast. The question is whether it's still acting like the same yeast you had before.

Of course, if you don't care about that, then obviously you can relax your standards.
 
A simple starter would have told you if it's still viable or not. IMO/IME, a few months should be ok. Provided it was kept at the right temperatures. How long ago did you pitch the slurry? Without knowing the cell concentration, and how much you pitched, it's virtually impossible to say if you pitched enough, or far too little. Give it the normal 72 hours before you start looking to get newer yeast.

My Starter started after i added alot of yeast nutrient about twice what it says to use.

Give it a day or so on the test wort and see. If it is starting much more slowly than the strain usually starts, that's not a good sign. It'll probably still work, but it indicates that the yeast is not behaving like it did before. It's likely it will perform differently in other ways as well.

If it never starts, then obviously it's shot. Some suggest that a small quantity of lower gravity wort (~1.020) can be a better way to awaken a sluggish sample.

If the yeast smells *bad*, then I would probably discard it on that basis alone. I have a starter going from some yeast I rinsed and harvested in November (almost 2 months ago) and it smelled pretty much like fresh yeast. It took off in a half-liter of 1.020 wort, and then chewed through 2.5 liters of 1.040 wort in less than a day with vigor, odor, and appearance that were very similar to a pitch with fresher yeast from the same generation. That's what you want to see.

If you're unsure, ask yourself whether it's worth risking a batch of beer on this yeast.

The yeast smells like hops and skunked hops but it doesnt smell like its decomposed or terrible. I guess ill see what happens after its completely done with the starter to see if i need new yeast. My lhbs is closed on sundays and mondays though.
 
My Starter started after i added alot of yeast nutrient about twice what it says to use.

The yeast smells like hops and skunked hops but it doesnt smell like its decomposed or terrible. I guess ill see what happens after its completely done with the starter to see if i need new yeast. My lhbs is closed on sundays and mondays though.

Sounds like you didn't do a decent job of washing the yeast then. You shouldn't have had any hop aroma, or other aromas, present in the slurry.
 
I used leaf hops and i can see small yellow pollen-like things in my slurry i think thats where it came from. I'm never very careful when i wash my yeast.
 
I don't wash my yeast and they store well under beer in the fridge, in the dark. 3 months is somewhat long to order but there are many experienced brewers who have viable yeasts stored even longer.

I'm curious about the skunk though. If the yeast turns out alive, i duno if the skunk will affect the beer. Chances.are that it won't be detectable (1 litre starter vs 5 gallon wort) but then we have a low threshold for the skunk smell.
 
Well, good luck. Odds are very good it'll make beer for you, and probably even good beer, though as I said, I'd be a bit hesitant to use something that smelled bad *before* it went into the fermentor. I'd say you at least want to crash and decant that baby and pitch as little of the skunked wort as you can. Alternatively, you could probably re-rinse from your starter. If it's really funky, that might be worth the trouble.
 
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