Need recommendation for yeast storage

[Tobor_8thMan]

Normally I brew using the same yeast until I feel I've done enough with the yeast and don't want to risk mutation, etc. Often this gets very boring.

While on a bicycle ride today I had a great idea. I have 2L and 5L flasks (these take up a LOT of room in the fridge between brews). Why not have a smaller way to store yeast for repitching. This way I can brew, for example, an ESB, save the yeast, then brew a wheat, save the yeast, brew something with a US-05, save the yeast, etc. As long as I reuse the saved yeast within a reasonable amount of time, perhaps feed it properly before using again, I'll be able to brew different beers without brewing the same over and over and over just to use 1 type of yeast.

I'm looking for recommendations on what to use for probably about 1L of yeast. Doesn't take up as much room as a flask (the flat bottom sucks up a lot of fridge space).

Thought about using already used small water bottles, but I'm not comfortable with the indentations (for sanitation reasons), etc in the plastic bottle for reuse. Also, the water bottles (from Costco, BJs, etc), seem very cheap and probably only good for 1 use.

Thanks.

 

[murphyslaw]

Mason jars work well

 

[Tobor_8thMan]

Great idea. Are Mason jars 1L?

 

[Tobor_8thMan]

Answering my own question. Yes. 1 liter (0.26 gallons or 33.8 oz). Walmart has a 6 pack of Mason jars for $10.98. What about the seal on the top? Use included lid (what about pressure? Is there any?)? Normally with a 2L or 5L flask I use a rubber stopper and airlock.

 

[Stand]

It sounds like you are comfortable harvesting yeast. If you want a LOT of strains, yeast banking is the way to go because you can store for a couple of years.

If you just want 2-4 strains Mason jars would be great, but I have never stored yeast like that for more than 2-3 months.

Others can speak to viability under those conditions.

 

[Tobor_8thMan]

2 to 3 months is ideal/fine for me. Thanks for the input!

What should I use for the top of the Mason jar?

 

[Coffeeturnal]

The included lids work just fine. If you have continued fermentation (has occurred for me in a fridge when using kveik), you can leave the lid a little loose. The center part will stay sealed well enough and will just burp itself if CO2 builds up.

 

[Stand]

The included lids work just fine. If you have continued fermentation (has occurred for me in a fridge when using kveik), you can leave the lid a little loose. The center part will stay sealed well enough and will just burp itself if CO2 builds up.

I wait like 2-3 days after harvesting to let CO2 offgas and then I tighten down the lid to keep stuff from getting in. They are meant to handle a vacuum, so they should be OK with a little pressure, but not much.

 

[smata67]

I use boiled 16 oz mason jars filled to about the 3/4 mark post fermentation when I don't filter the trub from pot to fermenter. I pitch that directly after warming to room temperature into 5 gallon beers up to about 1.070, which is where most of my brews end up. I get about 4 of these jars for the trub left over after a typical fermentation. From a bucket, easier to collect. Usually just score the trub into four portions and scoop into the jars. For the first week or two I have the airlock on it in the fridge, eventually replacing with a tight cap, though I have heard many people skip the airlock. I try to use within 6 months. On the cap, I write the yeast type, the date harvested and the generation. I have never had a problem doing this for about 20 brews. I may even believe I get better results than the initial pitch due to the much larger cell count.

I too want to economize fridge space and build some stock so I am actually switching over to filtering from the brew pot to the bucket to end up with mostly yeast at the end of fermentation. I have measured the dump from the brew pot and came up with 2.5 lbs (about 4 oz of this hops), so there is plenty of space to be saved. My plan is to fill these 4 oz (100ml) squat mason jars to about 3/4 and then make starters going forward, obviously not possible with my old system, too much trub to spin. White Labs vials are 30ml and the yeast usually compacts to about 15ml, for a 6 billion cell/ml or so count. I figure to end up with about 75ml of slurry, 5x that volume. Along with a 1L or so starter and I'm sure I'll be fine, but I haven't actually done this yet.

 

[RPh_Guy]

Answering my own question. Yes. 1 liter (0.26 gallons or 33.8 oz). Walmart has a 6 pack of Mason jars for $10.98. What about the seal on the top? Use included lid (what about pressure? Is there any?)? Normally with a 2L or 5L flask I use a rubber stopper and airlock.

Pitching a liter of yeast slurry into a 5gal batch is WAY too much.

Use a pitch rate calculator to help estimate the necessary amount.
https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

 

[Tobor_8thMan]

Pitching a liter of yeast slurry into a 5gal batch is WAY too much.

Use a pitch rate calculator to help estimate the necessary amount.
https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

I brew more than 5 gallons

 

[Tobor_8thMan]

Thanks for all the great input. Most appreciated. If I use an airlock for a few days, what size stopper for the mason jar?

 

[RPh_Guy]

I brew more than 5 gallons

Gotcha!

To put an airlock on a mason jar you'd need to drill through the lid. Just leaving the lid a little bit loose is fine -- about 1/8 - 1/4 turn from tight.

 

[smata67]

No stopper. A 1/2" hole is drilled in the mason jar cap with a spade bit and an airlock grommet slipped on it, a regular drill bit will not make a clean hole. The loose cap is a good idea.

 

[Stand]

Second RPh_Guy. Mason jars are made to release pressure during canning and they will work here too No need to do anything else. I fill them with Star San and leave the upside down to make sure you get good contact on the lid before filling them (I boil the too, but I figure it can't hurt).

 

[whovous]

Pitching a liter of yeast slurry into a 5gal batch is WAY too much.

Use a pitch rate calculator to help estimate the necessary amount.
https://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

What are the consequences of pitching too much yeast this way?

I read about many people pitching directly onto the yeast cake of the previous brew, which would imply even more yeast. Is this just as bad? Worse?

 

[RPh_Guy]

There are potential issues from over pitching like reduced stability from the extra trub, reduced yeast expression, lower attenuation, autolysis flavors, and excessive acetalydehyde or VDKs, besides the inherent risk of contamination and mutations affecting yeast performance that is present with any form of reusing yeast from a cake.

Disclaimer:
Home brewers use all manner of different methods, and they all make beer. It's perfectly fine to continue doing whatever works for you and your own goals and taste preference.

Cheers

 

[Tobor_8thMan]

Read thru all the replies again. I do appreciate everyone's input on my question. I'll go with the mason jars. What a great idea. So obvious too. Guess so obvious I didn't even think about using them. Doh!

Anyway, thanks to everyone.

 

[smata67]

I estimate a 1.070 (6.5% ABV) beer of 5.5 gallons yields about 1,000 billion cells at the end of fermentation. In my system, I have had success directly pitching 1/4 of the resulting cake into 5-6 gallons. I have gotten approximately 700ml (24 oz) of yeast slurry when I have filtered out the brew pot into the fermenter (the pic shows this, about 1/2" thick slurry at the bottom). I do this with a nylon paint bag over a sifter. So 1/4 of this, or 6 oz, could be directly pitched into 5 gallons, we are talking about 250 billion cells here. Or alternatively, and this is how I plan on going forward since I now have a stir plate, I can fill a squat 4 oz jar 3/4 the way to store half of this amount (3 oz) for a 125 billion cell count. At brew time, I would use a single jar to make a 1L starter and end up with 250-300 billion cells. I will most likely do 1.5L to be safe. The squat jars are going to save a ton of space, I have been using the pint jars which can't really be stacked like these little ones.