Let's Freeze Some Yeast

[SBOB]

Wyeast changed their packaging?

 

[Mardoo]

And their website.

Edit: Just to clarify, the substance and structure of the packaging seems the same. It's not a major change like White Labs

 

[Midnight Brew]

Wyeast 1450 frozen on the 9.11.2014 with a 15% glycerine solution.

15ml vial > 100ml by 1020 starter > 1.2L by 1040 starter.

2+ years!!!

 

[kcurnow]

Wyeast 1450 frozen on the 9.11.2014 with a 15% glycerine solution.

15ml vial > 100ml by 1020 starter > 1.2L by 1040 starter.

2+ years!!!

IMG_0422.JPG

2 years!!! Thats ridiculous, I may have to defrost some of my longuns and see if there is any life in them also.

 

[Midnight Brew]

Got some 1318 that I'll fire up in the new year for a round of milds. By that point they will be at the 3 year mark.

Zombie apocalypse come at me.

 

[Lethaldog]

Can someone please explain the process to me in simple form cos .... well I'm a little simple[emoji23] I'd like to give it a go as I know how to grow and split smack packs but I don't brew enough to not consider freezing!

Cheers
Leigh

 

[Mardoo]

1. Get 50ml autoclavable vials from a lab supply place.
2. Add 25ml of 50/50 glycerine/water solution.
3. Put caps on loosely
4. Pressure cook for 15 or so minutes
5. Let cool
6. Get smack pack
7. Smack pack
8. Let swell
9. Get 5 of your 50ml vials of solution per smack pack
10. Pour contents of pack evenly into vials
11. Let vials rest 2 days in fridge
12. Shake vials well
13. Put vials into a container filled with ice and allow to freeze. It may not go solid because of the glycerine
14. Thaw when you need to use and pitch into 1.020 wort for first step, 1.040 for subsequent steps.
15. Grow yeast

There may be a stirplate involved in that last bit. Ideally, but not absolutely required. I think that covers it.

 

[Lethaldog]

Awesome Mardoo I just screen shotted that shit for a later date cos I have one eye closed at the moment just trying to focus ( not quite but close) thanks I will definitely be having a go at that!

Pressure cook for 15 minutes? Do I need to get a pressure cooker or just boil in a pot?

Put vials into a container filled with ice?
Is that strict or can I just put them in the freezer?

Does it matter if the vials are plastic or should they be glass?

 

[angus_grant]

You can get plastic vials which are auto-clavable pretty cheap.
I've been microwaving my vials as I don't have a pressure cooker. Same process as Mardoo listed though.

 

[Lethaldog]

You can get plastic vials which are auto-clavable pretty cheap.
I've been microwaving my vials as I don't have a pressure cooker. Same process as Mardoo listed though.

how long would you need to microwave them for?

 

[Mardoo]

There are a fair few "good practice" things in yeast freezing you can probably sneak past if you want, but I figure they're simple enough that the added effort is minimal.

Pressure cooking pretty much guarantees no possibility of infection from encysted or spoored bacteria. Boiling is probably good enough, but I'd definitely go Angus' microwave method over boiling, once he tells you what it is. I'm not willing to risk probably, myself. You can pick up a pressure cooker for $10 or so from an op shop. I got mine for $12. Aldi sells a cheap one that lots of folks on this thread use.

You don't have to put the vials into a container with ice when freezing. However, the faster the yeast gets to freezing temperatures, the better the viability you should get. Pretty sure that was from the yeast book, but I may have seen it in a study. Can't remember. It's not uncommon for a vial to not actually freeze if it's ended up with an extra bit of glycerine. However, it's at freezing, and I haven't yet had problems with viability from one of these vials.

You don't have to use glass vials. You can if you can find ones with secure lids.

 

[angus_grant]

I've only done a few batches so not really commenting from experience. Haven't actually roused any yeasts from frozen sleep yet, so grain of salt....
Microwaved for 10 mins. Not melted any vials yet.
Pretty sure yob (or someone else) has talked about microwaving vials.

 

[Tony121]

I've only done a few batches so not really commenting from experience. Haven't actually roused any yeasts from frozen sleep yet, so grain of salt....
Microwaved for 10 mins. Not melted any vials yet.
Pretty sure yob (or someone else) has talked about microwaving vials.

Just to confirm, the solution is in the vials when you microwave or do you do that separately?

 

[angus_grant]

Yep glycerine/water in vial.
Cool vial down before adding yeast to avoid cooking your yeasties.
Just replace step 4 of Mardoo instructions with microwaving

 

[Tony121]

Thanks Angus.

Thought I'd try out with rinsed yeast from my last batch. Still need to refine technique but got there in the end;

Lid too loose = overflow in microwave
Lid too tight = bang (yes I know obvious, but microwave needed a clean anyway so thought I'd give it a bash and see what happened)

Anyway, will see how they end up in a few weeks/months time.

 

[Schooner_downunder]

Just starting to get into yeast freezing but just wanted to check if there is any difference between vegetable and petroleum based glycerine.

 

[Mardoo]

You want vegetable.

 

[Midnight Brew]

Wyeast 3068 destined for a dunkelweizen.

Date frozen : [SIZE=11pt]24.01.2014, 10% Glycerine[/SIZE]

3 years to the day.

100ml 1020 starter for 48-72 hours ---> 1L 1040 starter for 24 hours

 

[SBOB]

I revived my first frozen vials which was a 7month old wyeasy1056

0.5L 1.020 for 24 hours then 2L 1.040 and was decent activity after another 24 hours

Are those steps the 'recommended' or should I adjust volumes/step sizes?

 

[Moad]

thats what I run with mate, I then decant most of the 2L starter and spin up another 2L @ 1.040 for double batches