Creating a yeast strain from 2 yeasts

Hey everyone,

I want to preface that I know this sounds a little nuts and most likely won't work, but hey, why not try right?

A little background:
I have a nice big stock of yeast in my frozen yeast bank and decided I want to take on a little project. I am putting together a project for a belgian quad, and decided I really want to do something kinda neat. I am going to blend two proprietary strains together and ferment with that.

Now, this got me thinking and I kinda just let my imagination take control...What if I just took some of this blend off to the side and just kept feeding it, and letting it multiply, do some selection, and keep going etc. I know yeast do not undergo sexual reproduction...atleast not readily, and they mostly use asexual reproduction via budding and binary fission. However, there is genetic transfer that can occur. I wonder how long it would take to produce a culture that was a true offspring of the two original strains and basically call it my own.

I know it would take a lot of selection and plating, colony selection, re-growing, doing test batches, etc. etc. but this could just be a small side project to take up for fun. Just wanted to see what other people thought.

Thanks.
Kyle

Sounds interesting and like a lot of work. I would think you'd get substantial mutation before you'd get a "true offspring" but maybe thats what happens? Who's to say what a true offspring would be?

You may want to have a target style of yeast in mind before you start such an ambitious yeast manipulation project? I don't know?

That being said, personally I wouldn't and don't let anyone tell me I can or cannot, should or should not do this or that when it comes to my most freeing and experimental hobby of: brewing.

Yeast on my friend

I thought if you pitch more than one strain that only the most dominent strain will ferment. ...just an educated guess here, however....

I suspect COLObrewer is right that you would get a mutation/evolution of one of the two yeast strains way before you'd ever get any genetic transfer across the two strains. There's so much budding & asexual reproduction going on that there is more opportunity for this. And the real problem is that you wouldn't ever really be able to know whether any changes that occur in your yeast are caused by asexual reproduction or a genetic combination of the two strains. But either way, even if it's caused by mutations/evolution, it'll still be your own unique yeast strain that has evolved to your unique brewing environment.

Don't do it. Solar systems will collide and life as we know it will cease to exist!

Or not...

I just read somewhere that pilsner urquell uses a blend of 4-5 different strains. So you'll probably be fine.

That being said. I would expect if you try to wash that yeast and repitch a few times, you will end up with whatever the strain which was most adapted for your brewing conditions.

robertbartsch said:

I thought if you pitch more than one strain that only the most dominent strain will ferment. ...just an educated guess here, however....

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Yeah, I suspect one strain would dominate and just take over before any transfer of genetic material between the two strains would actually take place. Sounds like an interesting experiment to try, though.

Of course there are more than one strain of yeast in alot of different beers, up to 20+ different strains or more. I would think that more than one strain in these beers will influence the outcome, how would the other strains survive through numerous generations as in the case of say McEwans scotch ale if they were supressed by a dominant strain? I would wager more times than not there are more than one strain of yeast influencing the majority of fermentations.

you could plate out your yeast at expose them to a mutagen, like UV radiation. Then isolate each colony and grow up a small amount. Then ferment candidates using the same batch of wort. Screen for mutants that improve flavor.

This is not how yeast strains normally come about. Normally they just are a mutant of one strain. I heard that alcohol is often used in labs on yeast as a mutagen.

I bet if White Labs and Wyeast use DNA recombinant technology also. That's way more than anyone can do at home, unless your home is a hi-tech lab with necessary equipment and enzymes at hand.

I've read it takes very particular forms of stress to induce meiosis, and these condition are apparently different for different yeast strains.

And let's say, for sake of argument, that you are able to get two parent yeast to produce an offspring via meiosis... An issue to consider is the less genetic difference there is between the parent strains, the more likely it will be that your offspring will have the same characteristics (in terms of flavor contribution to beer) than one of it's parents.

Before you jump in on this, it might be worth it to pick up a micro book, or a book on yeast handling.

Maybe the new yeast book by JZ and CW will shine some light on creating your own yeast strain.

Brewer_Bob said:

Yeah, I suspect one strain would dominate and just take over before any transfer of genetic material between the two strains would actually take place. Sounds like an interesting experiment to try, though.

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This is my understanding as well.

IMO, your best bet would be to split your batch into 2 (or more) fermentation vessels and pitch each one with a different yeast. Ferment and then blend them together at bottling.

I have had quite pleasant results with this method.