Keeping yeast going

[TAXMACKEM]

Can someone explain to me how to keep yeast going indefintely ( or as long as poss),also about getting it infected (lots of detail please, I'm Over 50,hehehe) I havent a clue. Ive only ever really used packet yeasts for my wine.

[TAXMACKEM]

Cheers Chris,what about freezing it

[TAXMACKEM]

and if split into little bottles,how long will they keep in fridge and would I have to keep feeding them?

[delboy]

can be difficult to do, basically the freezing causes the formation of ice crystals that rupture the yeasts cell walls.
In the lab we would use liquid nitrogen to flash freeze them (the quicker the freeze the smaller the ice crytals and the less likely they are to cause rupturing).

Or you can try freezing them with a cryoprotectant like glycerol/glycerine which should have the same affect.

Probably just best to keep them in the fridge for a few months and reculture now and again.

[TAXMACKEM]

cheers Del, if they will keep without re-feeding ,for months, I'm a happy bunny

[iowalad]

Using Jim's method I have used some of my splits at 7 months. It takes a long time for them to get going and you have to step them up to proper size.

[Gurgeh]

I routinely save yeast in the freezer using a 20% glycerin, 80% cooled boiled water mix. only had one difficult thawing and i'm not worried about that - yet!

[TAXMACKEM]

Step them up to proper size?

[TAXMACKEM]

Oops, just read this, cheers Daab .

[Martin the fish]

It's fairly simple, just make a bigger starter than you need, pitch most of it and add more wort to whats left or, harvest it from the bottom of the fermenter and reuse the slurry (loosen with preboiled cooled water, split it 2-3 ways and store in pet bottles in the fridge).

Is there a more in depth thread to this DaaB? Especially the re-use of slurry from the fermenter.

This sounds very interesting and something i would find very handy i think...