Advice on 2.5 gallon batches and yeast usage

[ersheff]

Hello.
I live in a small apartment but have switched to all-grain, so I'm a 2.5 gallon BIAB kind of guy.
Since smack packs and dried packets are meant for low to medium gravity 5 gallon batches, I would normally pitch the entire contents of them into a high gravity 2.5 gallon batch (in lieu of making a starter).
However, what about when I'm making a standard gravity batch?
When it comes to dry yeast, I can just pitch part of the envelope, but unless I'm brewing another batch immediately, that seems like a waste of the remaining yeast.
With liquid yeast, it's more complicated.
I don't have money to spend on more equipment, so making and maintaining specific sized starters might not be feasible.
Perhaps I can just make a little mini starter with half the yeast and refrigerate it for a couple of weeks in order to "preserve" the remaining yeast until next time?
If I did that, could I use screw top bell jars to seal them after the yeast have been chilled and gone dormant?
Advice?

 

[JJL]

You can check mrmalty.com to calculate your pitch rates. But, in general, for an average gravity beer, you are looking at pitching 1 full liquid yeast pack or half of a dry yeast pack for 2.5 gals. You could wash your yeast after each batch. Typically you can get 4 batches out of the yeast harvested from from 1 batch. In addition, each washed batch will get you 4 more batches, and so on until you've washed it 3 or 4 times.

If you wanted to preserve half the dry pack, you could make a starter with it and then cold store it. It will keep a few months if it's an ale yeast. Although, I think I would just try putting the half pack of dry yeast in a plastic zipper bag and store it in the fridge. Dry yeast tends to be pretty hearty.

 

[tre9er]

For liquid, as mentioned, use 1 vial for 2.5g.

For dry, rehydrate it ahead of time in a sanitized container with preboiled/cooled water. Then cap it and cold-crash it to settle it out. I'd do this the night before. On brew day let it warm to room temp while you brew and at pitching time, shake it a bit to combine, then pitch half of it and return the rest to the fridge. Use mason jars, soaked in star-san or boiled first, for all of this.