Long Term Yeast Storage.

[Chris Mills]

I've been looking at ways to store yeast long term and am finding plating (or slants) to be an easy process (even if it does need doing every three months).

I've been reading about using distilled water as a long-term storage medium (at room temperature), and if money were no object and I had all the room in my brewery that I could want (I don't) I'd look at at cryogenic storage in aliquots stored in liquid nitrogen.

I'd like to have this a thread for discussing yeast management. Anyone want to join in?

[Ralph]

Oh ok. I take it you are being super careful to keep your distilled water sterile when you are opening it then?

Liam, I would think a standard pot still would do distilled water just fine.

[Liam Callaghan]

Hey guys any update on the long term storage?  Water and without refrigeration?

[Chris Mills]

I'll be making some new slants next week. I'll let you know what happens.

[Liam Callaghan]

Sweet!

I just ordered my glassware, thanks for all the help guys, very excited to get under way at last! 

Unfortunately I decided to remodel my workshop before culturing yeast so I have a nice clean area and plenty of bench space, so another weekend of hard work is looming...  Will be so worth it when its done though...  I hope :)

[Ralph]

I just roused my first yeast out of my frozen yeast bank 2 days ago. Got up and going no problem at all. Had been in the freezer for about 6 months.

2 step starter on the stir plate. First was 500ml for a day, then 1L for a day. Pitched it into last nights brew about 48 hours after taking the vial out of the freezer and there was good krausen on the brew this morning. Stoked that the method works and is quite easy. It is a great way to spread out a $20 packet of yeast.

[Liam Callaghan]

Thats awesome Ralph!

[Chris Mills]

After 5 months at room temperature my original DWS yeast culture is viable to propagate onto slants. I'm getting dozens of colonies as opposed to the thousands I got several months back, but that it is still going after that time (and Summer to boot) is rather encouraging. I'll try starting a slant from one of the refrigerated DWS cultures in a few weeks and we'll see what that's like.

[Liam Callaghan]

Hey guys, just a quick question.  I have got my slants up and running, nice and easy.  I have screwed the lids down tight and taped around them and popped them in the fridge.  Should l have put the lids on loosely to allow the c02 to escape and am I running any risk of high pressure c02 killing my slants?

[martin w]

i think that once they're in the fridge they could stop they're co2 producing activities go to sleep?i'll check the yeast book and post back if it has different information

[Grant R Baker]

Ditto... straight into the fridge sealed tight.  I have only done a  few so far but no problems.

[Chris Mills]

There is some CO2 produced off of slants.  The main thing is to keep dust from being sucked in when you open slants (or anything really) as bacteria often will hitch a ride on dust and can contaminate things.

It's more likely that you'll rupture your container if they are over active and you seal them too tightly.

[Liam Callaghan]

I'll stop worrying about that then and get to worrying the serious stuff :p  Thanks guys