harvesting yeast from commercial beer

mrskittle

Active Member
Trial Member
Established Member
Joined
Jan 5, 2020
Messages
130
Reaction score
145
Points
43
Location
Duluth, MN
After a couple of batches of 'less than stellar' beer, I've done some thinking about what they had in common and have come down on the topic of harvested yeast. Just like a couple of cleaning and sanitizing threads here lately, I don't think anything I'm sharing is new but it's always good to have this discussion once in awhile.

I've tried harvesting yeast from bottles of a commercial beer a few times with mixed success. The first time was from a seasonal beer (Bells Oberon) that was really fresh. Probably less than a month. I put it through a stepped starter and got enough to pitch a 5 gallon batch and enough left over for a couple more batches. I just washed the yeast, kept it in the fridge, and used a starter when I needed it. However, I had mixed success with these subsequent pitches of yeast.

Just about a week ago I picked up a 12 pack of a year-round brew from the same brewery (Two Hearted IPA). I harvested the yeast from 3 bottles and went through the same process as before. However this time it didn't work out... After a couple days of no activity in the started I checked the date on the bottles and the beer was about 4 months old. While they still tasted good, the yeast wasn't viable anymore. After a few days, I did see some foam forming but it didn't look right. There was no dark schmutz on top like krausen and when I swirled it, the little bit of air that sneaks out around the foil stunk. After my first spoiled batch just a couple of months ago, I recognized the stink right away. It was infected!

Correct me if I'm wrong, but my understanding is: there are infectious bugs EVERYWHERE, including your meticulously sanitized brewhouse. All that cleaning/sani work we do is to minimize the risk of infection, not eliminate it. The point is to have enough healthy yeast that it easily outcompetes everything else and ends up being the only microorganism left after a few days of fermentation.

My thought with the spoiled starter is that the yeast either wasn't viable, or it was too old and sluggish that it lost the competition for resources and another wild yeast or bacteria took over.

The Takeaway
While harvesting yeast from commercial beers is a good way to try and get yeast that might otherwise be unavailable, it's a mixed bag.

First of all, you have to make sure the beer is relatively fresh. Seasonals are good for this but a really fresh year-round beer certainly shows up at the bottle shop on occasion.

Secondly, watch your starter closely. If fermentation doesn't get rolling right away you may want to think again. Even if the yeast wins the competition, a sluggish start might indicate an unhappy or tired yeast.

Third, If you get a good pitch of yeast from commercial beer, don't bother with trying to save some for another batch.
Again this goes back to the possibility of tired yeast. Coming from a commercial brewery there are a lot of uncertainties. Unlike somewhere that yeast production is the sole priority.
 
Right on all counts and:

- If stepping up from such a small quantity of yeast, your sanitation has to be exceptional. It's better to use equipment that has been sterilized in an autoclave than to try it with Star-San.

- Be aware that brewers are on to us: Some of them filter their proprietary yeast out, then condition with something else.

You can pitch the yeast forward just as with any other yeast. Be aware that the bacterial load in that initial sample was likely much higher than commercial yeast (as a rate). The yeast can be revitalized in a moderate gravity starter just like any other.

Aside from the fact that it was guys like Chris White working under microbiological lab conditions that got us a lot of the strains we use today, yeast you harvest from the bottom of a bottle is just as usable as those old original samples.
 
Again this goes back to the possibility of tired yeast.
That's the problem with trying to "capture" a yeast from a commercial brewery. Tired yeast has tired children. With all the yeast available to homebrewers, this practice is becoming a thing of the past. The fresher the yeast is from the yeast lab, the better the beer. The last yeast people were trying to get was the Conan strain, but now that is available and other yeasts that very similar to Conan are available too.

I have been brewing for 18 years or so and I haven't explored all the yeast available to homebrewers. It's a golden age for homebrewers.
 
Right on all counts and:

- If stepping up from such a small quantity of yeast, your sanitation has to be exceptional. It's better to use equipment that has been sterilized in an autoclave than to try it with Star-San.

- Be aware that brewers are on to us: Some of them filter their proprietary yeast out, then condition with something else.

You can pitch the yeast forward just as with any other yeast. Be aware that the bacterial load in that initial sample was likely much higher than commercial yeast (as a rate). The yeast can be revitalized in a moderate gravity starter just like any other.

Aside from the fact that it was guys like Chris White working under microbiological lab conditions that got us a lot of the strains we use today, yeast you harvest from the bottom of a bottle is just as usable as those old original samples.


- I just use a clear growler for my starter and after the bad batch, I put it in a pressure cooker for 15 minutes at 15 psi and also used some star-san just for good measure. Fool me once shame on you, fool me twice shame on me.

- I have read that some brewers treat the bottles with a different yeast but to this point, it seems to be mostly speculation. It's all about keeping that secret ingredient, well, secret. However, lucky for me the yeast from Bell's is now available on their website.

- I agree that it's absolutely usable, I just think you can't quite treat it like a fresh pack of commercial yeast.
 
That's the problem with trying to "capture" a yeast from a commercial brewery. Tired yeast has tired children. With all the yeast available to homebrewers, this practice is becoming a thing of the past.

Well put. My problem is that due to COVID, I have too much time on my hands and am always looking for something new or different to try. I need to keep my mind on more useful tasks like a fermentation chamber instead of screwing around with yeast.
 
Well put. My problem is that due to COVID, I have too much time on my hands and am always looking for something new or different to try. I need to keep my mind on more useful tasks like a fermentation chamber instead of screwing around with yeast.
Yes, I know the feeling. I’m stuck in a house and I make due with the ingredients I have to make beer. But it’s forcing me to brew in ways I never did before and the beer is not too bad.

Besides, playing with yeast is a lot more fun than building a chamber, at least to me.
 
Well said. I agree with everything you wrote here.

Taking a step back, you should think of bottle-harvested yeast as an experiment. While it will often work, it will not be as dependable as newly acquired yeast from your own healthy fermentations or from commercial yeast banks. As a result, it has a place when working on brewing a credible reproduction of beers where yeast is prominent in the flavor, using rare yeast strains from special breweries. Once you’ve got a clean sample, in your bank you’ll be set, but that might take a few tries.

Bell’s beer is pretty special to me, and they attribute a lot of their unique flavor to their house Belgian strain. They do sell it on their online storefront. If it is worth it to you to harvest it yourself, I’ve read that Oberon is a good source, and what they use for yeast harvesting, but we should just keep in mind that it might not multiply rapid enough to produce a clean sample for your yeast bank on the first attempt, even with exceptional sanitation.
 
Last edited:
After a couple of batches of 'less than stellar' beer, I've done some thinking about what they had in common and have come down on the topic of harvested yeast. Just like a couple of cleaning and sanitizing threads here lately, I don't think anything I'm sharing is new but it's always good to have this discussion once in awhile.

I've tried harvesting yeast from bottles of a commercial beer a few times with mixed success. The first time was from a seasonal beer (Bells Oberon) that was really fresh. Probably less than a month. I put it through a stepped starter and got enough to pitch a 5 gallon batch and enough left over for a couple more batches. I just washed the yeast, kept it in the fridge, and used a starter when I needed it. However, I had mixed success with these subsequent pitches of yeast.

Just about a week ago I picked up a 12 pack of a year-round brew from the same brewery (Two Hearted IPA). I harvested the yeast from 3 bottles and went through the same process as before. However this time it didn't work out... After a couple days of no activity in the started I checked the date on the bottles and the beer was about 4 months old. While they still tasted good, the yeast wasn't viable anymore. After a few days, I did see some foam forming but it didn't look right. There was no dark schmutz on top like krausen and when I swirled it, the little bit of air that sneaks out around the foil stunk. After my first spoiled batch just a couple of months ago, I recognized the stink right away. It was infected!

Correct me if I'm wrong, but my understanding is: there are infectious bugs EVERYWHERE, including your meticulously sanitized brewhouse. All that cleaning/sani work we do is to minimize the risk of infection, not eliminate it. The point is to have enough healthy yeast that it easily outcompetes everything else and ends up being the only microorganism left after a few days of fermentation.

My thought with the spoiled starter is that the yeast either wasn't viable, or it was too old and sluggish that it lost the competition for resources and another wild yeast or bacteria took over.

The Takeaway
While harvesting yeast from commercial beers is a good way to try and get yeast that might otherwise be unavailable, it's a mixed bag.

First of all, you have to make sure the beer is relatively fresh. Seasonals are good for this but a really fresh year-round beer certainly shows up at the bottle shop on occasion.

Secondly, watch your starter closely. If fermentation doesn't get rolling right away you may want to think again. Even if the yeast wins the competition, a sluggish start might indicate an unhappy or tired yeast.

Third, If you get a good pitch of yeast from commercial beer, don't bother with trying to save some for another batch.
Again this goes back to the possibility of tired yeast. Coming from a commercial brewery there are a lot of uncertainties. Unlike somewhere that yeast production is the sole priority.

I know it probably misses the main point of your post, but I thought I'd post it just in case you're interested. I've looked into this into the past because I really like brewing or attempt to brew clones of Bell's Two Hearted. And I also really like Oberon! Anyway, you can purchase Bell's house strain directly and they actually give advise on harvesting yeast from their beer.
http://www.bellsbeer.com/news/brew-bells-our-house-ale-yeast-now-available-purchase

Also, Milk the Funk has some excellent yeast advice and yeast strain lists. It may not pertain to the beers you like to brew, but interesting nonetheless.
 
Dont most big brewers pasturize the beer? I have gotten some yeast from microbrews from a fresh batch brewing! Also, got a batch from a distillery, turbo yeast I think, fermented very fast and made good beer!
 
Dont most big brewers pasturize the beer? I have gotten some yeast from microbrews from a fresh batch brewing! Also, got a batch from a distillery, turbo yeast I think, fermented very fast and made good beer!
Megabrew does. Some craft brewers do as well. Some filter the yeast out and a few bottle condition. Some of those use a commercial yeast, not their house yeast, to condition and a very few leave their house yeast in to do the job. But I could go over to Bent Barley with a jar and bring back as much yeast as I need. Propping up from sediment works and could be fun but it is a crap shoot.
 
My favourite brew from the last year is harvested from two commercial strains. I haven't found a commercially available saison that I really like so I just took it from two saisons I really loved.

If you're washing your slurry between batches to get as close to clean yeast you'll find you have a much shorter storage window than just storing it unwashed under beer. I make a starter from the unwashed slurry for each batch. I suppose the starter is a sort of washing and it also gives me a pretty vital set of yeast for the actual brew (if fed properly the tired children can create vital grandchildren).
 
Excellent point! I recall John Palmer doesn’t advise washing the yeast for this reason. I guess it makes “washing” yeast a bit of an irony at the home brew scale. If you need to (for example when you want to give some away as a gift) you could wash the 2nd generation, after you’ve built up a clean base you can go back to. Of course, you’d want to make a starter out of a portion of the washed yeast to ensure it was clean and healthy.
 
I found washing beer to be an annoying hassle so I stopped doing it. Slurry and/or overbuilds are way easier and more than good enough.

Hundel is right about approaching this as an experiment, small breweries are more likely to have harvestable yeast in a bottle which is how I have done most of mine. But other than interest and maybe boredom it is easier and more reliable to buy the first packet and build from there.
 
I have harvested yeast from a regional brewery and combined it with a harvested commercial dry yeast fresh out of the fermenter 45%/65%. I have used this yeast 3 times using a starter and the 3 beers have come out great.
 
When you combine yeast like that, one will out complete the other, so your blend only was valid for the first batch.
 
When you combine yeast like that, one will out complete the other, so your blend only was valid for the first batch.
Some sacchromyces strains will outcompete others, but not all. All of the Norwegian blends that I've heard yeast labs talk about have had multiple sacchromyces strains in the blend. And they're all many hundreds of pitches old. Then you add in the various brettanomyces strains that exist together and the various microbes (which is generally what I'm after when I combine yeasts from multiple manufacturers) and there's plenty of reasons to mix yeast captures from commercial breweries.

Though we can debate how dominance of one strain over another affects the beer until the cows come home...
 
I would be pretty skeptical of any yeast blend that I came up with on my own, whether harvested or commercial. I have heard of some commercial yeast producers making blends though. There seems like way too many variables to reliably do it on your own.
 

Back
Top