Reusing yeast

[yesjenks]

Hello All,

How do I reuse yeast? Scrape the Krausen off, pick with DME and warm water?

Thank you in advance for your help!

 

[HBKidJr]

I'm by no means a pro, but I did this over the weekend, so I'll tell you my process.

After I siphoned off the beer in my fermenter (I only do a primary) into my keg, I was left with the trub in the bottom.

The exacts vary in the next steps, but my next beer is fermenting and not infected (thus far), so I assume I did ok.

I took some distilled water and poured about 1/3 of a gallon into the fermenter and swished and sloshed to get everything suspended, making sure nothing was stuck to the bottom.

I poured the mixture into a sterilized pitcher and put it in the fridge for about an hour.

What you'll see when you get it out is that it's separated into three layers. Top is leftover beer and water, middle is yeast, and bottom is hop/grain remnants.

I sterilized some mason jars and poured the separated mixture into the jars, making sure to wait a few minutes between to keep the bottom layer as undisturbed as possible. Toward the end, I used a baster to suck up what I could.

That's it. Stupid easy to do. I poured two of the jars (8 ounce) into my next beer that same night and refrigerated the other 4 jars.

There are ways to weigh the yeast to get close numbers, but I'm not going through all that.

Good luck!

 

[flars]

I strain out my hop debris during the pour into the fermentor. Leave just enough beer in the fermentor, to cover the yeast cake, when racking to bottling bucket. Swirl it all up, pour into quart canning jar, might be a few ounces left in fermentor. After three or four days in frig, 300 to 400 ml of clean yeast under beer.

 

[yesjenks]

Wow, that seems way to easy!

I'm going to give this a try when I bottle my next beer.

Do I have to do anything to the yeast before reusing it? Or, just poor it into the ferment with the wort?

 

[HBKidJr]

Let it hit room temperature, just like pitching a smack pack or WL vial.

 

[flars]

Wow, that seems way to easy!

I'm going to give this a try when I bottle my next beer.

Do I have to do anything to the yeast before reusing it? Or, just poor it into the ferment with the wort?

I use Brewers Friend to determine viability %, after storage of two months or more, for info on ml to pitch or if a starter is needed. To use BF for repitching harvested yeast requires a little creativity. Slurry tab in BF can be used if the harvested yeast is less than one month since fermentation. BF viability % can be entered into Mrmalty for pitching information also. (Mrmalty viability calculator is way off, don't use it)
If you pitch the entire harvested yeast cake, that would be called an over pitch, unless the wort pitched into, is above 1.090. You will have enough harvested yeast for three to four more brews, and from each one of those brews, enough yeast for three or more brews.

 

[KeninMN]

I just brewed a Chocolate Milk Stout this weekend and reused Wyeast 1084 Irish Ale yeast that had powered through a Dry Irish Stout in four days, which I had brewed the weekend before that. So I racked the Dry Irish stout into a secondary carboy, swirled the yeast cake up off the bottom of the primary and then measured off two cups of slurry (per the calculator in Brewer's Friend) into a sanitized glass measuring cup. From there I poured it into a clean, sanitized primary fermentor. (I did this all while the Chocolate Milk Stout wort was cooling from the boil.) When the Chocolate Milk Stout wort was cooled to pitching temp I racked it right onto the yeast and then shook it up well. Fermentation activity was noted after four hours, full-on fermentation was noted after seven hours and active fermentation had ended within 60 hours.

 

[yesjenks]

I just brewed a Chocolate Milk Stout this weekend and reused Wyeast 1084 Irish Ale yeast that had powered through a Dry Irish Stout in four days, which I had brewed the weekend before that. So I racked the Dry Irish stout into a secondary carboy, swirled the yeast cake up off the bottom of the primary and then measured off two cups of slurry (per the calculator in Brewer's Friend) into a sanitized glass measuring cup. From there I poured it into a clean, sanitized primary fermentor. (I did this all while the Chocolate Milk Stout wort was cooling from the boil.) When the Chocolate Milk Stout wort was cooled to pitching temp I racked it right onto the yeast and then shook it up well. Fermentation activity was noted after four hours, full-on fermentation was noted after seven hours and active fermentation had ended within 60 hours.

WOW! That's crazy!! Will you reuse this yeast again? On average each batch has enough yeast to brew 4 more batches?

 

[ChiefIlliniwek]

There's a really good thread on washing and storing yeast:

https://www.homebrewtalk.com/f163/yeast-washing-illustrated-41768/

I used this to save some Wyeast 1098 English Ale yeast back in November. I haven't reused it yet, because I haven't needed this type of yeast since. I'll probably target my next brew around it. I'll definitely be doing this with the American Ale yeast I'm using this weekend.

Just make sure you keep everything sanitized, and you'll probably want to make a starter for your next batch, unless you're racking directly only to the yeast cake already in your primary.

 

[corycorycory09]

I'll echo what others have said...

1) Pour boiled (then cooled) or bottled water into your carboy and swish around
2) let sit for 20-30 mins until the yeast has settled on top of a layer of trub
3) Pour the yeast layer into a large container/jar, leaving the trub behind
4) Put in refrigerator and wait for an hour
5) It will separate again. Pour off the yeast into sanitized 1 pint mason jars, leaving behind the layer layer of trub.

You can pitch this without a starter for the next few days, but if you wait longer than that, I'd use a starter.

Best of luck!

 

[KeninMN]

WOW! That's crazy!! Will you reuse this yeast again? On average each batch has enough yeast to brew 4 more batches?

Probably not. I think I'm done brewing stouts for the season, moving on to IPAs and lawnmower beers. But I'll definitely do this again this fall.