How long is harvested yeast good for?

[Nola_Brew]

I have an entire shelf in my fridge dedicated to liquid yeast harvested from previous brews. Most of these are from last year through Feb of this year. All sealed in mason jars stored about 35-38 degrees.

I did brew a batch this year where I used harvested 1056 that I made a vitality starter. It sat on the stir plate for 36 hours at which point it appeared ready. I added to my wort and it took three days to get any activity. I could not get the FG down below 1.020. I brew 3 gal batches and used a pint jar of harvested yeast that was half full of yeast and trub (no hop). In the past, when using harvested yeast, I normally see activity within 12 -24 hrs. So I'm thinking in this batch the yeast was probably a good 9-12 months from harvest date and not in optimal condition. In hind site, probably should have pitched more even though Mr Malty said I used the correct amount.

With that said, would it be best to get rid of harvested yeast that's in excess of 12 months old? Or would it be best to just use two half full pint jars instead of one when making a starter/vitality starter? How would one know if harvested yeast is bad? Would there be a certain aroma or look?

I haven't brewed since Feb due to having surgery but now I'm ready to start back up but find myself somewhat transitioning to using dry yeast due to ease of use.

 

[J A]

I think you could probably use the viability calculation according to date and maybe assume that viability is slightly lower. If you've got activity, there are live yeast cells, but they may be pretty sparse. You could probably have done a second generation of the starter you made and it would have done fine.
If you've got strains that you want to keep, just do a series of starters or very small, low gravity batches until you get them built back up. In the meantime, dry yeast (use it all the time) or starting fresh with liquid strains you use a lot are both good ideas.
Glad you're back brewing. Hope all is well with your health issues.

 

[Nola_Brew]

I think you could probably use the viability calculation according to date and maybe assume that viability is slightly lower. If you've got activity, there are live yeast cells, but they may be pretty sparse. You could probably have done a second generation of the starter you made and it would have done fine.
If you've got strains that you want to keep, just do a series of starters or very small, low gravity batches until you get them built back up. In the meantime, dry yeast (use it all the time) or starting fresh with liquid strains you use a lot are both good ideas.
Glad you're back brewing. Hope all is well with your health issues.

Thank you for the reply JA. It was minor hand surgery( both hands)- still not 100% back but close enough.
I'm going to test out some Conan or 1318 this weekend for a possible brew next week. I have Conan that I harvested from a Blonde I did and I have a brew planned for next week where I will use Conan and will due a vitality starter this weekend.

 

[GFHomebrew]

Great thread idea @Nola_Brew I've just done a cull of my harvested yeast in my fridge and cut it down to 34/70 Wlp090 and m27 saison yeast. I had a few other yeast strains that I was really 50/50 on. I've read that if the yeast goes gray looking in the jar she's getting old? My oldest yeast is Wlp090 its 10 months old but I've been using it on and off in that period it hasn't sat for that amount of time. It's still responding well still tasting clean it's attenuating a little less around 81% last brew which is below average for this bad boy but I'm happy with that.

I've rarely had a beer take longer than 12 hours to hit its stride. I make 1 Lt starters for my ales and 2lt for largess I'll do two steps 1 @ 1.5 LT then chill decant than another @ 2 LT just to be sure to be sure.

 

[Nola_Brew]

Great thread idea @Nola_Brew I've just done a cull of my harvested yeast in my fridge and cut it down to 34/70 Wlp090 and m27 saison yeast. I had a few other yeast strains that I was really 50/50 on. I've read that if the yeast goes gray looking in the jar she's getting old? My oldest yeast is Wlp090 its 10 months old but I've been using it on and off in that period it hasn't sat for that amount of time. It's still responding well still tasting clean it's attenuating a little less around 81% last brew which is below average for this bad boy but I'm happy with that.

I've rarely had a beer take longer than 12 hours to hit its stride. I make 1 Lt starters for my ales and 2lt for largess I'll do two steps 1 @ 1.5 LT then chill decant than another @ 2 LT just to be sure to be sure.

I have some that's right at 12 mths. it looks fine and still smells good so I assume it's still viable to an extent. In the next week or two I'll be brewing another batch and I'll probably use harvested 1318 or Conan. What I may do is combine two pint jars into a vitality starter and see if that helps.

In the past I've rarely had yeast take more than 24 hrs to start, especially fresh liquid with a starter. I have used harvested yeast before with no issues or long lag times. Not sure what the issue was with the last time I used 1056. Could have been my error as I may have underestimated how much viable yeast there was in the harvested amt. What I'll do moving forward is underestimate and pitch more just to be on the safe side. Drinking under fermented beer wasn't the greatest. But I guess it's all part of the learning process.

I just find myself using dry yeast more now but I do still like using Conan or 1318. So I'll probably dump the other yeast I have and just keep these two along with the dry.

 

[Ozarks Mountain Brewery]

I switched to dry, its much more consistent but I do save the dry yeast slurry when I have a very good beer from it, I use it right away though most of the time, kept one for a week at 34 in a sealed jar and it was a monster, lost half of it out the top, i just moved it to room temp Ill be checking on it bin a few days

 

[GFHomebrew]

I have some that's right at 12 mths. it looks fine and still smells good so I assume it's still viable to an extent. In the next week or two I'll be brewing another batch and I'll probably use harvested 1318 or Conan. What I may do is combine two pint jars into a vitality starter and see if that helps.

In the past I've rarely had yeast take more than 24 hrs to start, especially fresh liquid with a starter. I have used harvested yeast before with no issues or long lag times. Not sure what the issue was with the last time I used 1056. Could have been my error as I may have underestimated how much viable yeast there was in the harvested amt. What I'll do moving forward is underestimate and pitch more just to be on the safe side. Drinking under fermented beer wasn't the greatest. But I guess it's all part of the learning process.

I just find myself using dry yeast more now but I do still like using Conan or 1318. So I'll probably dump the other yeast I have and just keep these two along with the dry.

I save mine in 250ml jars i always assume only 20ml of yeast slurry in these 2 step starter for lager i over build to keep back some for next brew has worked well so far.

Brulospher has a yeast pinch/save write up on his sitem

 

[Nola_Brew]

I save mine in 250ml jars i always assume only 20ml of yeast slurry in these 2 step starter for lager i over build to keep back some for next brew has worked well so far.

Brulospher has a yeast pinch/save write up on his sitem

I read it when it first came out which made me try the vitality starter. The first time I did it I had activity within 8 hrs. the second time 3 days. I need to re-read the article to re-familiarize myself with it.

 

[CRUNK]

It can be frozen and reused, it will hold in the freezer for up to 2 years, and you should be able to use the yeast for 7 to 10 generations.

 

[krackin]

I harvest slurry during my brewing season. I generally will use it within a couple months, most likely a couple weeks. I do most of my brewing fall through late spring. I'll generally go about 4 generations.

 

[GFHomebrew]

My upcoming Pilsner I'm going to use to build some 34/70 for my malty Marzen brew. I will have to dust up on yeast washing as I've not done this in a fair while. I know if I just dump the next batch on top I'll have way too much trub + it will be a major over pitch and on top of this its a larger so I'll have to chill it down to pitch temps before pitching anyway.

Is this on track.
5lt pre boiled then cooled overnight filtered tap water. Add this to trub once beer is racked off. Shake the heck out of fermentor to break up trub let settle for 5 mins then pour back some into pre boiled water container let this settle for 5 mins then pour this into boiled and sanitizer jars wack jars in fridge for 10 or untill trub separation then pour yeast off top into flask jar whatever for use on next batch.

 

[Nola_Brew]

My upcoming Pilsner I'm going to use to build some 34/70 for my malty Marzen brew. I will have to dust up on yeast washing as I've not done this in a fair while. I know if I just dump the next batch on top I'll have way too much trub + it will be a major over pitch and on top of this its a larger so I'll have to chill it down to pitch temps before pitching anyway.

Is this on track.
5lt pre boiled then cooled overnight filtered tap water. Add this to trub once beer is racked off. Shake the heck out of fermentor to break up trub let settle for 5 mins then pour back some into pre boiled water container let this settle for 5 mins then pour this into boiled and sanitizer jars wack jars in fridge for 10 or untill trub separation then pour yeast off top into flask jar whatever for use on next batch.

Sorry for the late reply. I harvest most of the time but I don't wash. I just fill a pint jar about 3/4 full with the slurry once I bottle. It's worked for me with no issues. I use an entire jar for a 3 gallon batch.
I've read so many articles about yeast washing and harvesting that I was driving myself crazy. From what I've read washing isn't necessary so I just don't do it.
Problem for me is I have an entire shelf in my fridge dedicated to harvested yeast jars. My wife is getting pissed so I told her to buy me a small fridge so I can keep my yeast and beer out of my main fridge. So far that hasn't worked.
I'm at a point where I'm tired of messing with liquid yeast and I just don't have the place for it. So I'll be saving only Conan and 1318 and using dry for the rest.

 

[GFHomebrew]

Yes im going to fo the same thing this comming brew. Ill sanitize my flask swirl yeast up and dump her in there untill ready to use.