Propagating yeast from sludge

I have saved the sludge from the bottom of a carboy with the intention of harvesting the yeast. I have about 2200 ml of 'solution'. The bottom 1 1/2 inches of my yeast flask is quite dense dark brown. The next 6 inches is a rather beautiful graduated brown color, and the top couple of inches is beer. How do I capture just the yeast from this solution? How do I know how yeast I will have captured?

 

If you read the sticky you'll see that it suggests adding boiled and cooled water and whirling, then waiting 20 minutes and pouring the liquid (the yeast part) into your yeast container (jar). You won't know how much yeast other than eyeballing and remembering what a wlp tube looks like with 1 bill cells.

 

There is no way to separate just the viable yeast from the trub. Yeast washing, as shown in the sticky, will pretty it up a little, but you will be throwing out up to 90% of your viable yeast. Cell counts I have done show that the only noticeable difference between the different layers is cell density, and not viability.

more information here:
http://woodlandbrew.blogspot.com/2012/12/yeast-washing-exposed.html

The only real way to know is with a cell count:
http://woodlandbrew.blogspot.com/2012/11/counting-yeast-cells-to-asses-viability.html

 

It's probably just a typo, but just to clear things up, a White Labs tube has about 100 billion cells. Also, if you want to take a guess by volume of the number of cells keep in mind that the White Labs tube is almost all yeast, and your yeast cake from the fermenter will have quite a bit of protein trub. I have generally seen the following densities:

Professionally packaged yeast (White Labs or Wyeast) 2 Trillion cells per liter.
Yeast slurry with very little protein and hop partials 1 Trillion cells per liter.
Yeast slurry that has a lot of break material in it 250 Billion cells per liter.

For comparison, the Mr, Malty slury estimator lets you adjust this from 750 Billion per liter to 4 Trillion per liter.

 

Very cool. Thanks for this.

 

Thank you for the positive feedback! Every two days there is a new post.

 

Woodland - I wash yeast to separate it from what I thought was the non-yeast material. Are you suggesting that it's just as good, if not better, to just keep all of the material together and create a starter with it like I normally would?

 

The way I see it, not washing saves time and reduces the chances of contamination.

 

Cool. I've done it that way before, and will give it a go again, but probably not with hoppy beers. I doubt that a little extra trub will have a big impact on 5 gallons of beer, but I could see a bunch of old hops doing so.

 

So could one simply do the following??

Sanitize a ladel, scoop out trub and put in a sanitized canning jar and put in fridge??

 

you could, but you don't even need the ladel. I just give the bucket a swirl to mix it up then pour into wide mouth mason jars. If you rotate the bucket a little while pouring not much spills, but if it does I just wipe it off the rim with a paper towl soaked in whisky.

 

not a typo. too lazy too remember big numbers.:cross:

That sounds like a plan to me. Only problem is having a jar wide enough.

 

I went to meijer and bought a dozen 8oz jars with lids for like $7 and plan to fill up as many as I can when my nut brown ale is done.

 

Thanks very much for the reply. What is the 'sticky' to which you refer?

 

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

stickys are at the top of forum sections