Blowoff Foam: Pure Yeast?

So, I have a Belgian Dubbel that’s going bonkers in primary and blew off the airlock last night. I set up a blow off tube, and I was thinking I’d try to capture a bunch of the foam. I’m assuming it’s basically pure yeast now that it’s pretty much a uniform off-white color (i.e., I no longer see hops remnants, etc.) but I wanted to confirm that assumption before I go to the trouble. Anyone know/harvest yeast this way?

OK, based on the layer of yeast at the bottom of the first, uncovered pot I ran the blowoff tube into, I’m gonna say this is a viable way to collect yeast. The next question is, what’s the best way to do it? I was thinking next time I’d boil some water for 20 minutes, cool it, pour it into a container, and then run the tube into that. Or, can I just use water with properly-diluted star-san in it?

You know I have almost posted this thread several times because I had the same idea but didn’t think that it would work for a few reasons. Feel free to correct me if I’m wrong which happens often.
First: You mentioned starsan which I thought of too but to me it seems like a bad idea to be washing yeast with anything like that, even if it is safe for people and animals and used in your beers. It seems like a bad idea to me because yeast is very finicky…
Second: I try to only collect yeast from lower gravity beers but most of my blowoffs come from the high ABV beers from which I wouldn’t want to save the yeast anyways. I’m assuming the Belgian dubble falls into this category.
Third: I’ve never heard of someone doing this so I’m assuming there is probably a reason why.

Again; I could be wrong, but this is my line of thinking

I agree re: StarSan, but thought I’d ask. I’m much more likely to go with boiled water if I do this.

Interesting about not harvesting yeast from stronger beers. Why not?

The higher the gravity I think the harder the yeast have to work to get stuff done and they get stressed out and beat up doing that much work. Yeast don’t really like environments like that. It would be like telling a runner who usually runs three miles to run nine. They may finish, but they are not going to be in good condition afterwards. (That might not be a good analogy because our bodies recover and get stronger afterwards that but I’m sure you get the point).
I harvest all my yeast from beers below 1.060 for this reason.

are you thinking something like this?

http://www.beersmith.com/blog/2009/10/1 ... ff-method/

Ive seen some pretty slick burton union projects for collecting yeast, including this one:

http://www.byo.com/stories/projects-and ... m-projects

Yeah, that’s what I’m thinking about. I didn’t read the whole second article, but I get the gist from the pics and I like the idea. Thanks for sharing!