Is re-using yeast safe?

[BitterRat]

I wash to get all the trub/hop trash off of the yeast. If I didn't I'd be adding bitterness to my next batch.

I have not noticed this extra bitterness!!
But, I do not use pellet hops, so there is no "hop trash" to be concerned with. But you could over chill your beer, then let it stand for a couple hours, rack to your primary off the trub and hop trash, then pitch your yeast. You then have left most of that behind and can have a clean ferment.

 

[homebrewer_99]

I have not noticed this extra bitterness!!
But, I do not use pellet hops, so there is no "hop trash" to be concerned with. But you could over chill your beer, then let it stand for a couple hours, rack to your primary off the trub and hop trash, then pitch your yeast. You then have left most of that behind and can have a clean ferment.

That's true...about the pellets, I mean.

 

[Drunk Monkey]

gelatin or agar is a growth medium for the yeast. that with a little bit of yeast nutrient and DME.

basically you boil a cup of water w/ some dme and yeast nutrient.. add some gelatin as it cools and pitch into your test tubes. maybe 1/4 to 1/3 full.

you take your test tubes and autoclave/pressure cook them to sterility.. then you innoculate the congealed agar or gelatin with a 1st generation yeast (right out of a yeast packet). it would be a good idea to do 3 test tubes per yeast strain just in case you end up with a bad one..

then you leave these out to grow until you see colonies form..

they are now freezeable for up to a year (some folks add some glycol to help freezing).

I'm just now getting into it myself, but that's the gist of it.

Ultimatately the objective is to have enough yeast slants on hand to be able to pull out a vial, scrape out some yeast and toss it in a small 200ml starter and step it up to 1000ml and pitch it.

Imagine having 30 strains of yeast in your freezer at your disposal.

yessh i went overboard with my description.. you just asked why gelatin. perhaps you already do slants using agar.

I am interested in this method because i would like to save yeast for awhile. Do you have a webpage that gives more detailed information?