• Yeast

Yeast

The good thing about yeast is that no matter how clueless you are, the tough little buggers are hard to kill.

• /Culturing My first go at making slants. More links and info here specific to culturing and storing yeast.

• StirPlate - turbocharge your starters with a home made magnetic stirrer.

• Brewing Science Brewing science yeast care

• Brewsters yeast Has a huge list of yeasts available as slants.

• Fermentis (previously DCL) Yeast

• White Labs

• Wyeast Labs

• Danstar

• Bodensatz Brewing Yeast Database

• Homebrew Yeast Strains Chart

• Brew Rats "Yeast Specifications"

• Yummies for Yeast Care and feeding of your yeast.

• Yeast Equivalents Wyeast and Whitelabs equivalents.

• Yeast Information and Technique Resource a fact packed resource at brewery.org.

Microbiology

• Brewers Laboratory Handbook: Brewing without the blindfold

A Makeshift Centrifuge

I acid washed some yeast I had in a test tube prior to pitching into a starter. After an hour I realized it wasn't settling too well which posed a problem. If I put the pH 2 solution into a 10x starter then I am going to be around pH 3 - which is not great conditions for yeast. OTOH most texts recommend stepping up starters at no more than 10 times the volume. I couldn't leave the yeast in the acid wash for much longer because apparently the yeast can't survive the pH 2 for very long. As it turns out, I was being a tad paranoid and I forgot the buffering power of wort. See StirPlate for more on this.

I had a bit of a brainwave - a makeshift centrifuge in my lathe. A drill press could do the same thing but I had the bits handy. The more yeast I could settle out, the less acid solution would have to go in the starter.

The solution in the test tube started out as a creamy liquid with no obvious settling.

This is after 5 minutes at 250 rpm. Getting somewhere, but slowly. I decided to live dangerously and wind it up to 550 rpm.

This is what it looked like after 15 minutes at 550 rpm.

Yeast Farm

And after a couple more days, after putting most of the starter in my latest APA, my very own yeast farm. The bent aluminium is designed to fit in a pressure cooker along with (empty) test tubes.

Note that I dont store yeast like this anymore (under beer). My current method uses [\Culturin agar slants] eg:

Intelligent Yeast

Look what the guys over at Brewlab have been cooking up (I just liked the picture of krausen that looks like a brain):

The Krausen alone is smarter than most brewers.

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