Top Cropping Yeast Collection

Has anyone attempted to collect and store yeast at high krausen? I posted in the general beer forum but got no responses. Apparently if you are NOT a complete newb and actually have question other then about no airlock activity or some other is my beer ruined query nobody cares lol... not bitter though!

I'm looking for some general techniques about doing so and storing for about 1week. How much krausen? How much sterilized water, etc. Thanks!!

You should pick up a copy of Jamil and Chis White's Yeast book. He describes a couple of methods of top cropping. I remember reading that with top cropping you're harvesting the healthiest of the yeast. One method he talks about is just using a sanitized spoon, another method involves some CO2 and vacuuming the yeast out.

http://www.amazon.com/Yeast-Practical-Fermentation-Brewing-Elements/dp/0937381969

Yup. Here's what I do:

1) Ferment in a bucket for easy access
2) Use a santized spoon to skim off the initial dirty krausen (after 24-48 hours depending on your yeast and temp). Discard.
3) About 24 hours after the first skim, skim again with a sanitized spoon, but this time put the yeast in a sanitized jar with some boiled and cooled water (use bottled if your tap water is chlorinated) in it. Try to get nothing but clean yeast when you skim (no wort, not left over scum). I collect about 1/4 - 1/2 cup of yeast and put it in a pint size mason jar with about cup of water in it.
4) Cover the jar with the sanitized lid and put it in the fridge until you need it. I've pitched directly from the jar after three weeks of storage with no ill effects. I've also used yeast that I've stored this way after 6 months. I did make a starter for that batch, though.

I've been thinking about this myself. I've been collecting yeast after it falls out, then reusing this for the next starter many times. The problem with this is that I'm pitching cells from the first batch that are likely long dead.
What I'm planing on doing is as follows (or some slight variation on it):
Make a small starter with an olde yeast culture I have
Skim off a little of the krausen (with out siring up the bottom)
put the skimming into another small starter
Step up this starter
Once it clears decant and use the cake (wash and save, or pitch)

This should provide a heather (and less dead) culture. Using the method; there shouldn't be a limit to how many generations I use, as long as I don't mind the mutations which occur.

Many strains are easier to top crop than others: wy1968 and wy1318 will have a healthy and bountiful yeast mat to harvest from 36 hours into the fermentation. Wy1469 and wy1187 also give a good sized harvest, but it is less in my experience.

I've tried top cropping US-05 from reports of people having success with it, but it pretty much only throws a second cheesy krausen after the first skim on dark brews for me, so it is too unreliable for me. Weird, I know, but the three porters I brewed with it had the typical yeast mat after the first skim (altough it had more bubbles and less yeast than the english strains). The other 3-4 batches of light beer never threw a second krausen !

I have a specially modified blow-off bottle (sealed.....with an airlock) that I fill with boiled water instead of starsan to collect the blow-off with. After fermentation settles down and I switch back to an air lock on the FV, I swirl up the settled yeast/sterile water mix in my blow-off bottle, pour it into sterilized mason jars, and toss it in the fridge for the next brew. Kind of a redneck Burton Union.

Much cleaner and easier than washing from the trub and the yeast seem to be much healthier too. YMMV.

thughes said:

I have a specially modified blow-off bottle (sealed.....with an airlock) that I fill with boiled water instead of starsan to collect the blow-off with. After fermentation settles down and I switch back to an air lock on the FV, I swirl up the settled yeast/sterile water mix in my blow-off bottle, pour it into sterilized mason jars, and toss it in the fridge for the next brew. Kind of a redneck Burton Union.

Much cleaner and easier than washing from the trub and the yeast seem to be much healthier too. YMMV.

Click to expand...

That's a great idea. Do you have a pic of your setup?

It's just a 1 gallon juice bottle, I poked a hole near the top and inserted a grommet to put the blow-off hose through (and down into the water) and the cap has a grommet with an airlock installed.

I'll try to take/post a pic later.

I've actually been trying to think of a good method to retain the "blown" off yeast... I would like to see a picture as well ! Thanks for all the great ideas!

Here's a pic (grommets removed for cleaning):

As for the how much, it all depends. I have found this slurry estimation from Wyeast very helpful.its at the bottom of the page.

after you collect about 1 liter of your blow off, you can put it in the fridge and let it floc out. then you estimate what % of the yeast is of the total slurry. and then you can use their estimate counts to get a ballpark approximate of your yeast count.

eg, of 1000ml of slurry collected, 350ml of yeast settle out of solution. so you have ~35%. According to Wyeast you should have 8.7X10^8 (87,000,000)or 87 million cells/ ml x 350ml = 304.5 billion cells.

It helps to have a mason jar or a flask with volume markings.

thughes said:

Here's a pic (grommets removed for cleaning):

Click to expand...

That's pretty slick, and right at my price range. I think I'll try something similar out next brew.

Bsquared said:

after you collect about 1 liter of your blow off, you can put it in the fridge and let it floc out. then you estimate what % of the yeast is of the total slurry. and then you can use their estimate counts to get a ballpark approximate of your yeast count.

Click to expand...

Ok - this makes sense - So you'd then have to account for the initial volume of sterilised water that you had in your blow off bottle?

Use something that has gradations, so you can see your total collected volume.

I just top-cropped a single heaping sanitized ladle's worth from an IPA which had been in primary bucket for four days. I moved dirty krausen out of the way first. I put it in about 2.5 cups of 1.070 wort I paper towel filtered from the trub of the fermenting beer (and recently re-boiled). I scooped a bit of liquid with it. It's going crazy in the mason jar right now an hour later. I plan on adding the whole thing to 5 gal of new wort tomorrow. This is my first experience harvesting yeast. Here's hoping boiling and Star-Sanning everything pays off and neither batch gets spoiled. Never contaminated a batch but these are only batch numbers 5 and 6.

The power of top-cropped yeast...

I pulled 1/3 cup of US05 yeast off the krausen of an APA last Saturday for reuse Sunday. Things came up so I put it in the fridge. Today I made a small 0.75L no-shake starter just to get it ready for tomorrow and build a few more cells. Clearly not needed. One hour later I have this. It's bubbling like mad and still building.

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