harvested yeast - should I do a starter or not

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Pdaigle

Well-Known Member
Joined
Jul 25, 2015
Messages
382
Reaction score
9
People are saying I should not do a yeast starter with yeast I harvested a few weeks ago. Should I DO or NOT?

Also I have jar of slurry. How do I know if I have enought. Im afraid to screw that one up.

if I pitch and I don't have enought, how will I know if I don't have enought?

Brew on!!
 
always do a starter.

There's ways to calculate approx how many yeast cells you have. But a starter will get you new fresh yeast for your beer. You also have a better idea of how much yeeast you have once its ready.

You wouldnt use leftover dirty water to mash with, why do the same with your yeast if you have the choice?
 
Three week old yeast will not need a starter. The yeast is still full vitality, unless it was harvested from a high gravity fermentation. How many yeast cells you have per milliliter is variable. Pictures of your harvested yeast and the procedure used to harvest would help.

This post will help you decide how many yeast cells you have in your slurry.
https://www.homebrewtalk.com/showthread.php?t=519995
 
You wouldnt use leftover dirty water to mash with, why do the same with your yeast if you have the choice?
That's just silly. A batch of beer is not that much different than a large starter. If you're coming from an average gravity beer and have a fresh, clean, properly harvested slurry, there no need for a starter.

Use a caluclator to determine how much yeast you need. You'll get 1 to 1.5 billion cells per ml of thick slurry (after decanting beer from top of chilled and settled slurry).
 
Three week old yeast will not need a starter. The yeast is still full vitality, unless it was harvested from a high gravity fermentation. How many yeast cells you have per milliliter is variable. Pictures of your harvested yeast and the procedure used to harvest would help.

This post will help you decide how many yeast cells you have in your slurry.
https://www.homebrewtalk.com/showthread.php?t=519995

Does this help?

image.jpg
 
I would use a count of 2 billion cells per milliliter for the purpose of repitching this yeast. This is probably on the conservative side, but I like to error towards over pitching just to be safe.
 
People are saying I should not do a yeast starter with yeast I harvested a few weeks ago. Should I DO or NOT?

Also I have jar of slurry. How do I know if I have enought. Im afraid to screw that one up.

if I pitch and I don't have enought, how will I know if I don't have enought?

Brew on!!
If people are already saying do/don't make a starter why ask more people thinking you'll get less of the same? Just pick one and go with it to see what happens. Plenty of people repitch yeast cake (me included) from months ago and have no problems. Other people don't. The missing information is all the data about the yeast. What it fermented before, storage temps, amount, density, healthy, etc.


You'll know if you have enough if you can get a solid cell count using lab equipment. Everything else is a guess. Even WITH lab equipment it's a guess/assumption. You won't know if you have enough/too much but your beer will probably ferment just fine. Brulosophy has done a few and he used math to calculate his cell count based on the volume of yeast cake in his jar and online calculators. I believe he pitched about 473mL and wanted to pitch 500 of solid dense yeast cake to make up 280 or so billion cells. I'd pitch a pint of yeast cake based on his math and if I had less I would do a starter. You won't screw it up. If it isn't enough and the yeast only get 60% attenuation you cold buy a pack of yeast to finish it off and take notes based on how much you pitched.
 
always do a starter.

There's ways to calculate approx how many yeast cells you have. But a starter will get you new fresh yeast for your beer. You also have a better idea of how much yeeast you have once its ready.

You wouldnt use leftover dirty water to mash with, why do the same with your yeast if you have the choice?

is it possible to kill yeast if I poored hot water when harvesting?
 
is it possible to kill yeast if I poored hot water when harvesting?

Yes, absolutely.

I'm also concerned about how much head space is in that jar.

Personally, I don't bother with a starter if the yeast I'm repitching was harvested less than 2 months prior. But I know I'm collecting exceptionally clean yeast (I have very little trub in my fermenters).

In your case, however, if you're concerned you may have killed the yeast by rinsing with hot water, I'd recommend a starter to verify viability.
 
I always make a starter if I have harvested/washed yeast. I usually have about 1/2-1" of nice light beige yeast at the bottom of my mason jar. I decant the liquid on top, warm the slurry up, shake it up and pitch it into the cooled starter wort. I've done it this way for 1.5 years without any issues.
 
Yes, absolutely.

I'm also concerned about how much head space is in that jar.

Personally, I don't bother with a starter if the yeast I'm repitching was harvested less than 2 months prior. But I know I'm collecting exceptionally clean yeast (I have very little trub in my fermenters).

In your case, however, if you're concerned you may have killed the yeast by rinsing with hot water, I'd recommend a starter to verify viability.

that's what I was thinking and if I see activation does it mean Im good?
 
120°F May kill some of the yeast. 130°F Will kill all of the yeast, or leave so few viable cells that there won't be any recovery.
 
Back
Top