Commercial Yeast Harvest Questions

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Sensei_Oberon

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So I'm now venturing into the yeast harvesting arena. I expected this to go horribly wrong....

I boiled a half cup of DME in 2 cups of water, cooled and then carefully added the sediment from 3 Bells Two-Hearted Ale bottles to a growler with a little yeast fuel. I then capped the growler with an upside-down jar, allowing oxygen exchange (I sanitized everything).

I don't have a stirplate (plan to make one) so I just swirled it several times a day. After about 5 days now, there is some gunk on the surface. I'm hoping it is a sign of fermentation, but it looks more like mold.

Has anyone encountered mold doing this? Does it sound like I'm on the right track? I don't want to bother with another generation if it has been contaminated. How do I know if it has been funk-dified?

Thanks, I'm mostly trying to learn from the process.
 
Have you made a starter before? We really need pics to make sure it is not krausen you are seeing, though that should have happened in 24-48 hours not 5 days. What color is the "gunk"? Is it bubbling? Is there whitish globules growing in the bottom? You should be able to see a significant amount of yeast in the bottom of the growler at this point. What does it smell like?

It would be better to use sanitized foil than an upside down jar. If you are concerned, maybe it would be best to pitch it and try again. A stir plate is definitely helpful for oxygenating the yeast, but it is not necessary for success. More info!!!!
 
Sounds like krausen to me.

Revvy, would it take 5 days to show active fermentation? That was my main concern. I have never harvested from a commercial brew, but I wash yeast and pitch very small amounts to a starter and always have activity way before that.
 
I could take more than 5 days if that beer has been sitting on a shelf for a while. The longer the yeast has been dormant, generally the longer it takes to get going again. For one of my pacman harvests it took a week to show any visible signs of fermentation.
 
I didn't think photos would do much but it seems they do. I can see a yeast cake forming, and if I look really close that moldy gunk seems to be very tiny bubbles.

So I'd say success! Without a stirplate, would you guys recommend I decant and repeat?

If I manage to not screw this up through 3 generations, I was planning to store the wort in some Tupperware or something else that seals well with virtually no head space.

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It takes as long as it needs to actually. But there's really no such thing as active fermentation usually where starters are concerned. Here's some basic info I have posted on here countless times.

Sounds like your starter did it's thing......It doesn't matter one blip in your fermenter or your starter flask if the airlock bubbles or not (if you are using an airlock and not tinfoil if you are using tinfoil, you aren't getting bibbling anyway,) or if you see a krauzen. In fact starter fermentation are some of the fastest or slowest but most importantly, the most boring fermentations out there. Usually it's done withing a few hours of yeast pitch...usually overnight when we are sleeping, and the starter looks like nothing ever happened...except for the little band at the bottom. Or it can take awhile...but either way there's often no "activity" whatsoever....

I usually run my stirplate for the first 24 hours, then shut it down, if you are spinning your starter it is really hard to get a krausen to form anyway, since it's all spinning, and there's often a head of foam on it from the movement.


All that really matters is that creamy band o yeast at the bottom.



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This is a chilled sample so it's flocculated, but even with an unchilled sample you should see a band of yeast at the bottom. Here's an unchilled version

starter.jpg


Same thing, a band.

As it is I've only ever seen two or three krausens actually on my starter (one blew off a bunch of krausen and knocked the tinfoil off the flask,) and the evidence of one on the flask at the "waterline" once. But I've never not had a starter take off.

Look for the yeast at the bottom, don't worry what it looks like on top.

If you have yeast on the bottom....that's all you really need.

If it looks anything like that, your are ready to either feed it again, or use it.

Your picture looks to me that you have yeast, and maybe a krausen on the top, have your recently fed it some more wort to step it up? I would.
 
Looks like success to me! Kinda hard to see w/ the brown growler and fuzzy pic, but that looks like a uniform head of krausen not mold.
 
You got the room, don't decant, especially if you have krausen.

Makes sense. One more question: in the pics you posted did you pitch from there (the starter in the pub glass, for example) or decant? I would like to hold off pitching for a couple weeks if I can. I was mostly just experimenting (didn't expect this to actually work).

Thanks
 
Makes sense. One more question: in the pics you posted did you pitch from there (the starter in the pub glass, for example) or decant? I would like to hold off pitching for a couple weeks if I can. I was mostly just experimenting (didn't expect this to actually work).

Thanks

Those are just web pics, not mine. It's really up to you, some decant, or some just swirl it all in. One factor to consider is whether or not the "starter beer," the liguid on top smells sour or not. Often, especially in the summer it may sour in only a few hours. Some folks add a hop pellet as a preservative/preventative measure. The couple of ounces of sour beer wont really affect the taste of your finished product (unless maybe you were brewing an extremely light tasting beer.) It's really up to you.

Another factor is whether or not the yeast is a low flocculating yeast and there may be a lot still in suspension. The "beer" will be cloudy rather than clear-ish. If it's a witbier or hefe yeast for example it might be better just to swirl and pour it all in, you'll get the max number of yeast cells that way.

My starter flask is huge and often I will build up a starter over a few days and end up with 1 1/2 to 2 quarts of "beer" in it. If the yeast has pretty much flocculated I will, if I have time cold crash it like the web pic above, but even if I don't I will carefully pour off all but about 2 cups of the liquid, then swirl the remainder to re-suspend the yeast and dump it in my fermenter.
 
My starter flask is huge and often I will build up a starter over a few days and end up with 1 1/2 to 2 quarts of "beer" in it. If the yeast has pretty much flocculated I will, if I have time cold crash it like the web pic above, but even if I don't I will carefully pour off all but about 2 cups of the liquid, then swirl the remainder to re-suspend the yeast and dump it in my fermenter.


I think I'll add some wort and really get it going, add a couple hops, cold crash, decant and plan to pitch. Then I will have an excuse to brew a new batch....

Many thanks
 
Hey guys, this is really cooking now. I gotta say making a starter is probably more fun than a batch. Thanks for the tips.

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You might have delayed signs of fermentation because you put a fairly small amount of likely several month old yeast from the bottom of the bottles into a decently large amount of wort. It may have taken a while for the reproductive stage of fermentation to have concluded before they really went to town chewing on the sugars. Obviously you have healthy fermentation going on so there's nothing to worry about.

In the future you may want to make your first wort in a smaller quantity to make it easier for the yeasts to get through the initial reproduction quickly which will help you get viable yeast and diminish the likelihood of infection.
 
In the future you may want to make your first wort in a smaller quantity to make it easier for the yeasts to get through the initial reproduction quickly which will help you get viable yeast and diminish the likelihood of infection.


I was nervous about infection, but it smells like green beer, so I'm not too worried now. I added some fresh wort today (and the bottom 1/2 oz of a couple more Two Hearteds tonight for good measure). Is there any reason I can't keep adding some more fuel steadily (until I run out of room) to really get a good yeast cake and/or delay pitching?
 
I was nervous about infection, but it smells like green beer, so I'm not too worried now. I added some fresh wort today (and the bottom 1/2 oz of a couple more Two Hearteds tonight for good measure). Is there any reason I can't keep adding some more fuel steadily (until I run out of room) to really get a good yeast cake and/or delay pitching?

Really you only want to wait about 2 weeks between cranking up your yeast cake. After then, you'll loose 50% of the viability of the yeast (according to JZ in his book "yeast."). What I do when harvesting from a bottle is grow the yeast in a very small amount of low gravity starter wort (1.020) to get the yeast a bit healthier and then plate it out to make sure there is no bacteria or mold. After that it goes into a slant or start the process of stepping up starter sizes to a pitchable rate.
 
Looks like yeast to me. Bell's yeast is not very flocculant and doesn't produce a big foamy krausen like some yeasts, so it looks about "to spec" to me.
 
Really you only want to wait about 2 weeks between cranking up your yeast cake. After then, you'll loose 50% of the viability of the yeast (according to JZ in his book "yeast."). What I do when harvesting from a bottle is grow the yeast in a very small amount of low gravity starter wort (1.020) to get the yeast a bit healthier and then plate it out to make sure there is no bacteria or mold. After that it goes into a slant or start the process of stepping up starter sizes to a pitchable rate.


Should I be overly concerned about yeast health and viability without using a stirplate? (pitching infected yeast into a batch would obviously be not good)
 
I make starters and step up yeast all the time without a stir plate. Although I'm sure it helps the only starter related problem I had was trying to make a starter out of very tired yeast. Even that eventually fired up.

Just give it a good swirl for a minute as often as you can.
 
Like everyone else already said, a stir plate isn't necessary but it sure helps. Using the stir plate keeps the yeast in suspension and keeps adding oxygen to the wort. Keeping them in suspension keeps the yeast munching on the wort. Adding oxygen keeps the yeast's lipid membrane pliable, which helps them reproduce.
 
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