Author Topic: Reusing Dry Yeast  (Read 1583 times)

Offline davidgzach

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Reusing Dry Yeast
« on: September 29, 2011, 06:11:35 AM »
Folks,

I've been reusing yeast for a while now, but pitched some dry US-05 in my red-ale.  I just kegged it and again, added some distilled water, swirled up the yeast cake and poured in to a container.  Got the typical separation, but it's liquid and trub.  There is no middle layer as with liquid yeast.

Can someone fill me in on what I am missing?  I figure I just save the trub with a little liquid on top and go with it.

Dave
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Offline blatz

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Re: Reusing Dry Yeast
« Reply #1 on: September 29, 2011, 06:45:41 AM »
its no different than any other yeast, liquid or dry.  sometimes it is just hard to get that separation.  just dump/decant the liquid off the top and pitch all the yeast and other solid.

FWIW, US-05 repitched is a monster - you may see 3-4% MORE attenuation - YMMV.
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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #2 on: October 03, 2011, 01:55:22 PM »
WOW!  I pitched all the US-05 slurry from my Red Ale in to the Pumpkin Ale.  It was flowing out of the blow off tube in about 2 hours!  You're not kidding it's a beast.
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Offline maxieboy

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Re: Reusing Dry Yeast
« Reply #3 on: October 04, 2011, 03:24:12 AM »
WOW!  I pitched all the US-05 slurry from my Red Ale in to the Pumpkin Ale.  It was flowing out of the blow off tube in about 2 hours!  You're not kidding it's a beast.

More a function of the overpitch than the strain... ;)
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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #4 on: October 04, 2011, 04:33:38 AM »
It was a serious pitch but I wanted to account for the 1.067 OG.  First bubble in about an hour.....
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Offline blatz

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Re: Reusing Dry Yeast
« Reply #5 on: October 04, 2011, 06:35:43 AM »
It was a serious pitch but I wanted to account for the 1.067 OG.  First bubble in about an hour.....

did you check mrmalty.com to see how much you should have pitched?  if you pitched the entire amount you collected, then you did overpitch by at least double.  that's okay though - we've all done that at some point and in some cases, brewers noticed no off flavors or effects from the overpitch.
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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #6 on: October 04, 2011, 06:48:21 AM »
I respectfully disagree.  Plenty of brewers pitch directly on top of the previous cake, especially for higher gravity beers.  It is VERY hard to overpitch.  And Mr.Malty is a great guideline but not the end all of yeast pitching end alls.  IMHO of course.....
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Offline blatz

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Re: Reusing Dry Yeast
« Reply #7 on: October 04, 2011, 06:56:47 AM »
I respectfully disagree.  Plenty of brewers pitch directly on top of the previous cake, especially for higher gravity beers.  It is VERY hard to overpitch.  And Mr.Malty is a great guideline but not the end all of yeast pitching end alls.  IMHO of course.....

well I respectfully disagree - plenty of people do pitch on top of yeast cakes (most of the time when they are just learning about reusing yeast), and it is not a best practice.  and frankly 1.067 is not what I consider high gravity - I would not even consider pitching on top of a whole yeast cake unless the gravity of the wort was >1.100.

finally you are right - mrmalty is not the end all, but look at Chris White's book, look at wyeastlab.com's pitching calculator, look at sean terrill's work, and look at basically any professional brewing literature out there and you will find the same general guidelines.

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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #8 on: October 04, 2011, 01:45:10 PM »
They have the same general guidelines for proper (minimum) pitching.  I have not seen a guideline for overpitching.  If I am missing something I would definitely appreciate finding out so I do not make the same mistake twice.
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Offline blatz

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Re: Reusing Dry Yeast
« Reply #9 on: October 04, 2011, 02:11:59 PM »
They have the same general guidelines for proper (minimum) pitching.  I have not seen a guideline for overpitching.  If I am missing something I would definitely appreciate finding out so I do not make the same mistake twice.

this is a good summary:  http://www.wyeastlab.com/hb_pitchrates.cfm

what is presented aren't minimums - they are the optimal prescribed rates, with a little wiggle room since we homebrewers generally don't have cytometers to be as precise.  so anything significantly over that rate is further from 'optimal'.

Yes, you can 'get away with' overpitching just like you can underpitching, but you why wouldn't you 'optimally' pitch?  It does make a difference - not so much for something clean and neutral like 001, but for some more ester/phenol abundant strains, it can have a significant effect since those aspects are restrained by the lack of need for growth - overpitched beer can be bland and 'flabby' is one way I have heard it described.

its sort of like if the recommended pressure for your tires is 35psi, and the max pressure for the tire is 120psi, yeah, you can fill it with 60PSI or 20 PSI, but you ain't gonna like the ride, and the tires are gonna wear out quickly - i'd rather shoot for 33-36 and do it right.

like I said above - you will more than likely be fine, but its not something I would purposely do with my beer.
« Last Edit: October 04, 2011, 02:13:57 PM by blatz »
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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #10 on: October 04, 2011, 02:15:22 PM »
I should also qualify out that I agree I pitched a lot of yeast.  I went from 1.051 to 1.067 and used probably 3/4 of the rinsed slurry.  And I definitely appreciated the advice to not worry about the stratification in the wash.  I just don't agree that I over-pitched.........
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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #11 on: October 04, 2011, 02:16:07 PM »
Thanks.  I'll check out that summary.
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Offline blatz

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Re: Reusing Dry Yeast
« Reply #12 on: October 04, 2011, 02:17:09 PM »
I over-pitched.........

maybe you didn't - but you didn't pitch the optimal amount.   ;)
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Offline davidgzach

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Re: Reusing Dry Yeast
« Reply #13 on: October 04, 2011, 02:18:36 PM »
LOL.  Let's agree on that one..... :D
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Offline euge

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Re: Reusing Dry Yeast
« Reply #14 on: October 04, 2011, 02:26:22 PM »
Four years ago it was common practice. I think people are getting away from it as they are getting more comfortable following established pitching rates. And the word is getting out.

Now I have a soup/stew ladle that holds about a cup. Use that badboy to scoop out a cup or so and pitch. Or divide the cake up into plasticware containers- date and refrigerate. 

Best though is to take some of the cake and build a starter. That way you have fresh yeast and very little trub in your repitch. I'm just as concerned about some other beer's old trub going in along with a bunch of dead yeast into my fresh wort.
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