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General Category => Yeast and Fermentation => Topic started by: KCguy on April 11, 2019, 11:53:02 AM

Title: harvesting commercial yeast out of dregs of bottle?
Post by: KCguy on April 11, 2019, 11:53:02 AM
Saw older threads about the release of the Unibroue yeast strain, but no longer available now.  So after drinking a few bottles of the Providential ale from trader joes, I reserved the last inch or so in the bottle and poured into a starter, set on the stirring plate, and....nothing happened. 

Anyone try this?   and succeed?  youtube videos, the source of all wisdom, seem to indicate its possible....thoughts?
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: Big Monk on April 11, 2019, 01:27:24 PM
Saw older threads about the release of the Unibroue yeast strain, but no longer available now.  So after drinking a few bottles of the Providential ale from trader joes, I reserved the last inch or so in the bottle and poured into a starter, set on the stirring plate, and....nothing happened. 

Anyone try this?   and succeed?  youtube videos, the source of all wisdom, seem to indicate its possible....thoughts?

Well, first you have to determine whether the brewery uses it's primary yeast strain for bottling.

If so, you have to determine how old the bottle is. The likelihood of being able to step the dregs up to a healthy, pitch able culture will be directly attributable to how long it's been in there.
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: hopfenundmalz on April 11, 2019, 05:03:16 PM
When I do this, I have a small volume starter to begin with, 500 ml or less. I also use the dregs from 2 or 3 12 oz. bottles. That might be a tough task with Unibroue bottles. ;-)
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: Slowbrew on April 11, 2019, 05:11:25 PM
I'm not familiar with this beer so this may not be relevant.

There may not be any yeast in the bottle.  If the beer is pasturized/filtered and then force carbed when bottled there won't be any yeast to grow.

Paul
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: Robert on April 11, 2019, 05:21:14 PM
I've had great success in the past culturing from a bottle,  and also complete duds.  Big Monk has nailed it on both counts.  Is it the yeast you want, and is it still viable.  The duds I've had have been strong and/or long aged beers.  Probably the right yeast but very few cells still viable, too few to see any visible action in the medium if there was any.  That's another point.  You may not see any activity in the first stage, but stepping it up enough times might build a viable culture.   However, the chances of infection are astronomically higher in that situation.
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: KCguy on April 12, 2019, 12:25:39 AM
Had a nice surprise when I went down to the brew area and found the mason jar full of Unibroue dregs and it was bubbling!  Active yeast culture forming I think....

About a week ago I had started this jar, with a starter of 3-4 tbsp of light dme and a pinch of yeast nutrient, as well as the last 4 ounces of about 4-5 bottles of Unibroue (from a long wkend).  It now appears to be building pressure, but Im unsure of what to do with it now. 

If I put it in the fridge, then it will slow down growth and go dormant.  Im inclined to transfer to an E flask, put a good airlock on it, and keep it in 60F temps for as long as it appears to be growing....

I have vague plans of brewing an Abt12 clone next week, so it would be right at home in there...or a tripel. 
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: Robert on April 12, 2019, 12:37:17 AM
Why transfer?  If it's happy, let it be.  As long as its covered so nothing can fall in, no need for an airlock either.  I don't think I even own one anymore and I do a lot of yeast harvesting/ wrangling.
Title: Re: harvesting commercial yeast out of dregs of bottle?
Post by: charlie on April 13, 2019, 01:48:16 AM
I have harvested yeast from several commercial brews. Bells 2HA, SNPA and Alchemist Heady Topper come to mind. The best procedure is:

1. Let the bottle (or can) sit in the fridge for 5 or 7 days.

2. Gently decant it into a glass saving the last 50 ml or so.

3. Swirl the bottle to re-suspend the yeast, and transfer it to a 25X100 mm culture tube with 100 ml of starter wort.

4. Let it sit several days while swirling daily. It may take a week or more for the few live cells to grow into something that you can see.

Charlie