On Sun, 05 Sep 2004 23:01:35 +0000, R.F wrote:
[color=blue]
> I know it's a living culture and I can't make it from scratch, but
> I am interested if it's possible to harvest a new yeast culture out
> of kraeusen. Somewehere on webI read about old trappist brewers
> who were knowledgable enough to collect kraeusen and grew a new
> culture whichwas also improvimg a taste with each new generation of
> their kraeusen cultured yeast. What's the procedure called ? Please
> can someone point to a web page which explain the process, or
> explain such yeast harversting. I was searching sites [url]www.byo.com[/url]
> and [url]www.reelbeer.com[/url], and could not find anything related about
> usefull purpose of collecting kraeusen.
>
> Thank you.[/color]

I do this all the time. I ferment in wide-mouthed vessels, so I just
sanitize a spoon, dip in there and scoop some out. I don't take a lot --
usually just about enough to 2/3 fill an old White Labs vial. I store
these in the fridge and use them as the basis for starters.

Some yeasts are better for this than others. WLP001, for instance, is a
very good top-cropper. It all floats to the top after fermentation and is
easily harvested. Safale S-04, on the other hand, sinks like a stone and
sets like concrete in the bottom, so if you want to harvest it you have to
get in half way through the fermentation. Of course, there's not much
point harvesting a dried yeast strain because it's so cheap to buy more.

Rodd