First time re-using yeast

[MannyEdwards]

I harvested yeast for the first time a couple of weeks ago, and it's been in the fridge since. I have a pint chock full of Nottingham, and it smells great, but I've never used harvested yeast before.

Can I just pitch the whole pint into my 5.5 gallons without making a starter? If it doesn't start, I suppose later I can pitch a new pack of dry yeast, and the harvested stuff won't ruin it?

 

[HB_in_Subic]

I have done that in the past without issue. I let the yeast warm up to the pitching temp, drain off the beer on top of it, then pitch into the bucket. It will kick off quick so make sure that you have a blowoff tube installed.

 

[Yooper]

Yes, but it probably is a massive overpitch.

I'd consult a yeast pitching calculator, like mrmalty.com (free on the desktop version) to get the right amount. A pint jar is probably enough for a 15 gallon batch. I use about 1/2 of a pint jar for a 11 gallon batch, usually.

For example, say your yeast is 2 weeks old. You and making an ale and the projected OG is 1.056 and your batch size is 5 gallons. You need approximately 125 ml of a medium-thick slurry for that batch. That is 4 ounces approximately- or 1/2 cup, or 1/4 of a pint.

 

[Gavin C]

I harvested yeast for the first time a couple of weeks ago, and it's been in the fridge since. I have a pint chock full of Nottingham, and it smells great, but I've never used harvested yeast before.

Can I just pitch the whole pint into my 5.5 gallons without making a starter? If it doesn't start, I suppose later I can pitch a new pack of dry yeast, and the harvested stuff won't ruin it?

According to Mr Malty which gives very pessimisting rates of yeast viability you need

260ml for a 5.5gallon batch of 1.055 wort.

Your pint should be more than enough. 1/2 pint is likely all you need.

I've used slurry before and not needed a blowoff. No more vigorous than other fements I've had.

 

[MannyEdwards]

According to Mr Malty which gives very pessimisting rates of yeast viability you need

260ml for a 5.5gallon batch of 1.055 wort.

Your pint should be more than enough. 1/2 pint is likely all you need.

I've used slurry before and not needed a blowoff. No more vigorous than other fements I've had.

Quite a handy reference, there. Many thanks!

 

[MannyEdwards]

Yes, but it probably is a massive overpitch.

I'd consult a yeast pitching calculator, like mrmalty.com (free on the desktop version) to get the right amount. A pint jar is probably enough for a 15 gallon batch. I use about 1/2 of a pint jar for a 11 gallon batch, usually.

For example, say your yeast is 2 weeks old. You and making an ale and the projected OG is 1.056 and your batch size is 5 gallons. You need approximately 125 ml of a medium-thick slurry for that batch. That is 4 ounces approximately- or 1/2 cup, or 1/4 of a pint.

Excellent, thanks.

 

[MannyEdwards]

Update: I pitched 1/2 pint into 5.5 gal of 1.057 wort, and it took off very nicely. I probably could have done with 1/4 pint, as Yooper mentioned, but I didn't really have any other use for it.

Related question: Has any of you gone more than 5 or 6 generations with yeast harvesting?

 

[m00ps]

Update: I pitched 1/2 pint into 5.5 gal of 1.057 wort, and it took off very nicely. I probably could have done with 1/4 pint, as Yooper mentioned, but I didn't really have any other use for it.

Related question: Has any of you gone more than 5 or 6 generations with yeast harvesting?

Ive gone more than 10 with some of my saison strains and the Conan yeast i use for all my IPAs. I harvest from my starters though so there is more consistency than you would get with harvesting yeast slurry thats gone through a whole fermentation and been exposed to hop compounds

 

[MannyEdwards]

Ive gone more than 10 with some of my saison strains and the Conan yeast i use for all my IPAs. I harvest from my starters though so there is more consistency than you would get with harvesting yeast slurry thats gone through a whole fermentation and been exposed to hop compounds

I want to try that! What do you do; stir it up and skim like a pint off the starter?

 

[Gavin C]

I want to try that! What do you do; stir it up and skim like a pint off the starter?

Read this great summary of harvesting from a starter here.

It's really very simple.

 

[MannyEdwards]

Read this great summary of harvesting from a starter here.

It's really very simple.

Per-fect. Thanks!

 

[m00ps]

Personally, I just make starter 4-5 days in advance to make sure they basically ferment out before I store them. I used to do the usual 1-2 days, but I started getting the lids almost bursting off my mason jars from the not-quite-fermented wort and yeast I would harvest

I make sure to leave the starter undisturbed for 24 hrs before pitching to get a nice dense yeats cake at the bottom. I decant the starter, fill a small jam-sized mason jar near to the brim with yeast, and pitch the remaining portion into my wort

 

[Gavin C]

Agreed 100%. I like the no-rush approach to timing starters.

I do starters Monday for a weekend brew.

48 hours on the stir plate, harvest the over-build and lightly cap and label the jars before tightening a couple of days later. 3 days in the fridge leasves a nice big fat firm yeat cake. Very easy to decant off the nasty starter wort.

Gotta love almost free clean yeast

Starter and extra yeast