Liquid Yeast Cultivation - Long Term Storage

[argon]

I plan to cultivate yeast from 2 packets of Wyeast before starting my next fermentation of 2 cubes I brewed on the weekend.
Wyeast German Ale 1007
Wyeast Northwest Ale 1332

I've done a bit of searching around about yeast cultivation and can't quite find the exact answer I'm after about cultivating yeast straight from the packet before fermentation.
I've had a read of the air locked article "Starting Wyeast" where ther's talk of just making a single starter larger and large over time then splitting it into X number of batches.
But can this be stored long term? (months?)

John Palmer talks about cultivating the harvested yeast from the Krausen or harvesting from the yeast cake then separating from the trub

Krausen Harvesting;
first skim off the green/brown hop and protein compounds with a sanitized spoon early in the primary phase. As the creamy white krausen builds up, you can skim this fresh yeast off with a sanitized spoon and transfer it to a sanitized jar. Fill the jar with cooled boiled water and place it in the refrigerator. The lack of nutrients in the water will cause the yeast to kind of "hibernate" and it will keep for up to a couple months. You should pitch this yeast to a starter after storage to re-vitalize it.

Yeast Cake Harvesting;
You can collect yeast from either the bottom of the primary or secondary fermentor. If you obtain yeast from the secondary, it will have only small amounts of trub mixed in and will be easy to separate. f you harvest yeast from the primary fermentor, you will need to separate the yeast from all the trub that is mixed in (etc, etc)

What I'd like to know is if I can split each pack into say 5 containers and add cooled boiled water to keep the yeast ready for subsequent brews. Or do I need to add cooled boiled wort as nutrients.

Most likely I'd be looking at keeping the yeast for a couple of months as I only brew once a month or so. Also, should I do this before or after activating the smack pack to add the nutrients to the yeast?
(Obviously I'll make starters for future brews in order to up the number of viable cells before pitching.)

Any feedback or further info appreciated.
Cheers

 

[Fourstar]

look up yeast slanting. Best option for long term storage.

 

[RdeVjun]

There's probably varying opinions on how to go about this sort of thing. I'm of the view that smacking and then splitting the pack into several separate boiled starter worts, growing them out, pitching one and then refrigerating the remaining starters that you don't use can work, and indeed has done for me for up to three months, but may not suit you. Storing post- ferment yeast cake in much the same way is also an option, as would be krausen harvesting, but again, all have a limited shelf life that may not quite suit your brewing frequency. BTW, The 1007 is a top cropper so krausen can be harvested, I'm not sure if 1332 is though.

But as Fourstar has suggested, slants are probably the best long- term option, but that's a whole new layer of complexity that may not be necessarily worth it, particularly when a fresh pack is less than $10 (excluding freight) and those two strains are always available (i.e. not PCs or otherwise hard to obtain). Its your decision though, at least if slanting goes pear- shaped the first time around, you can get a fresh pack to try it again! But you do risk ruining a cubeful if you notice it is crook only after you pitch it, so there is that risk to consider...

As with lots of brewing processes and methods, there's a handful of different ways to achieve much the same end!
:icon_cheers:

 

[Pennywise]

I've done a bit of searching around about yeast cultivation and can't quite find the exact answer I'm after about cultivating yeast straight from the packet before fermentation.
I've had a read of the air locked article "Starting Wyeast" where ther's talk of just making a single starter larger and large over time then splitting it into X number of batches.
But can this be stored long term? (months?)

This is how I split my Wyeast packs up and I've had no problems storing the stubbies for 4-5 months. Haven't stored any longer than that, but I think I will with a stubbie just to see. See how it holds up after a year.

 

[WitWonder]

At the end of the day technically all you need is one single cell from which you can culture more. Of course, this is almost totally impractical on a HB scale.

Rather than making starters from your smack pack and splitting that (which means you are storing second/third generation yeast for the most part), I take a pipette and take around 3x10ml from a pack and put in vials for later use then make a starter from what remains in the pack. Put the vials in the fridge and make starters as required from those, stepping up to 100ml then 1000ml and so forth.

 

[BjornJ]

At the end of the day technically all you need is one single cell from which you can culture more. Of course, this is almost totally impractical on a HB scale.

Rather than making starters from your smack pack and splitting that (which means you are storing second/third generation yeast for the most part), I take a pipette and take around 3x10ml from a pack and put in vials for later use then make a starter from what remains in the pack. Put the vials in the fridge and make starters as required from those, stepping up to 100ml then 1000ml and so forth.

That is something I have thought about as well, as I make a large starter, then split that into 4. (pitching one and keeping 3).
Wouldn't it be better to split the yeast before it starts fermenting, to keep the "Generation Zero" kind of purity.

Hmm.. Where do you get the tiny vials and what-not? Does pharmacies sell that kind of things?

 

[Screwtop]

What I'd like to know is if I can split each pack into say 5 containers and add cooled boiled water to keep the yeast ready for subsequent brews.

Search some more, lots of us have done this. Was a popular way of splitting packs a few years ago, search posts from 2005 - 2006 remember the time the yeast has been stored begins on the mfg date as it has not been cycled since manufacture.

Screwy

 

[argon]

Rather than making starters from your smack pack and splitting that (which means you are storing second/third generation yeast for the most part), I take a pipette and take around 3x10ml from a pack and put in vials for later use then make a starter from what remains in the pack. Put the vials in the fridge and make starters as required from those, stepping up to 100ml then 1000ml and so forth.

ok I think this what I'm after. I assume you take the samples of yeast before activating the nutrient.

 

[RdeVjun]

ok I think this what I'm after. I assume you take the samples of yeast before activating the nutrient.

Sounds like it to me.

I'd guess no, before sampling, don't smack it, just give it a stern talking to!

 

[floppinab]

ok I think this what I'm after. I assume you take the samples of yeast before activating the nutrient.

Yep prior to smacking or adding anything, I've been doing this now for some time with very good results and storage well into 10+ months. Keys IMO are of course the best sanitation you can manage on your split process (handling, vials, general environment), storage (as cool without freezing as possible), and then your starter process (again sanitation and I use a stir plate and run somewhere between 1.5 and 2.5L starters).

 

[argon]

Yep prior to smacking or adding anything, I've been doing this now for some time with very good results and storage well into 10+ months. Keys IMO are of course the best sanitation you can manage on your split process (handling, vials, general environment), storage (as cool without freezing as possible), and then your starter process (again sanitation and I use a stir plate and run somewhere between 1.5 and 2.5L starters).

So where is it you get thes vials from. Glass with rubber stop lids on a timber rack i'd expect?

 

[WitWonder]

So where is it you get thes vials from. Glass with rubber stop lids on a timber rack i'd expect?

No, mine are just plastic. Got the gear from a science supply place here in Perth. I haven't reused any but figure it would be OK with decent sanitation. They are so cheap and I have around 100 of them I haven't reused any since buying them - have just thrown them out after single use.

Oh and don't smach the pack before splitting - save the yeast nutrient for a beer!

 

[Nick JD]

Make a beer from the pack. Bottle it. Bottle the trub.

Sorted.

 

[WitWonder]

Not necessarily. There are some yeasts (e.g. 3068) which do not work well with older generations of the yeast which means you will not get the flavour profile you're looking for with that yeast if you repitch.

 

[Doogiechap]

I split and store mine in sample jars pre smack and store them under saline after getting this advice from someone who knows his stuff. I made up a glove box for working in to try to keep things as clean as possible.
Cheers
Doug