Storing the Yeast

[Battleaxe]

So two days ago I made a US-05 starter with no intention of starting anything... I had however used 1/5th ( I only brew 1 gallon batches) of the packet in a SmaSh and wanted to store the rest of the packet for future brews.

Now I have a 400ml starter do I:

1. Pour off 100ml into 4 mason jars and leave them in the fridge?

2. Let the yeast settle out pour off the spent wort and replace with boiled cooled water upto 1lt and pour 250ml into four mason jars?

3. Top up the current 400ml to 1lt and pour 250ml Into 4 mason jars.

The mason jars are roughly 250ml medium sized Kilner flavour.

Any other suggestions are welcome.

[hazelbrew]

i have used part of a packet before - Nottingham in my case.

I just left the remainder in the packet and sealed with tape. I figured the dry yeast is dormant and going to last longer like that.

now you have the starter what do you want to do with it? and when will you brew with it?

I would probably either:
- use new yeast next time and chuck this lot or
- keep the whole starter in the fridge to pitch within the next 4-6 weeks

[Battleaxe]

I want to use it in future batches, ideally stored as individual amounts x4 so I can make a new starter with each. I won't be brewing again for 2 weeks.

[BrannigansLove]

I harvest yeast by overbuilding starters. I just fill a large jar with the starter excess (shaken to ensure there is even suspension of yeast). I just leave it under the starter "beer". Never had any issues reviving. Jars are stored in the fridge.

[Battleaxe]

My issue is I have a starter that I want to split, obviously it will be under the "beer" but as it's quite small there will be a considerable air head space in the jars I intend to use, will this be an issue?

[Kev888]

The best answer is (unhelpfully for this occasion) not to make a starter, for two reasons: it isn't really appropriate for dried yeast and the remainder of the pack will keep better dried. Just rehydrate the small quantity you need to brew the batch in question.

As you've already made one then there are various options, but I would suggest making some splits - divide it into small containers for which you'll use one per brew. Theres a how to here and a slightly different approach here. You could store it in one batch but that means risking infection in the remainder everytime you open it to extract some. Again, I wouldn't normally recommend making splits with dried yeast, its only because you already made a starter.

Thats assuming you actually made a starter, if you just rehydrated it, i.e. in water, then it is sitting there activated but starved of nutrients. I believe its recommended to use that within about half an hour or so. Its been some time since the OP, so in that situation I would just discard it and chalk it up to experience.

[Battleaxe]

The best answer is (unhelpfully for this occasion) not to make a starter, for two reasons: it isn't really appropriate for dried yeast and the remainder of the pack will keep better dried. Just rehydrate the small quantity you need to brew the batch in question.

As you've already made one then there are various options, but I would suggest making some splits - divide it into small containers for which you'll use one per brew. Theres a how to here and a slightly different approach here. You could store it in one batch but that means risking infection in the remainder everytime you open it to extract some. Again, I wouldn't normally recommend making splits with dried yeast, its only because you already made a starter.

Thats assuming you actually made a starter, if you just rehydrated it, i.e. in water, then it is sitting there activated but starved of nutrients. I believe its recommended to use that within about half an hour or so. Its been some time since the OP, so in that situation I would just discard it and chalk it up to experience.

See I've searched and searched for info on starters, I understood that pitching the correct amount of dry yeast does give problem free fermentation but I got into the mantra that making a starter is always recommended to brew better beer...

I have previously used 3g of the pack in a brew so I didn't want to leave it open (taped up) for an extended period and saw storing the yeast as a split starter as a good way to A. Have yeast that I could step up easily and B. Store the yeast ready to be used.

[Kev888]

Starters are often good with liquid/wet yeast, largely because they don't keep as well so the number of viable cells can be quite low by the time we come to use them, or in the case of things like slants there may never have been enough cells to begin with. The purpose of the starter is to grow up the number of cells in a small volume of wort, so that when they are pitched into the main brew there are enough to avoid 'under pitching'. A secondary advantage is that the starter lets you check the yeast are healthy and working as expected before committing to the main batch.

Dry yeast however have a large number of viable cells and these keep considerably longer, so unless its an old or very badly stored pack theres no great need to grow them up for a standard sized batch of normal gravity. Additionally dried yeast are quite sophisticated in that they are packed ready to go, with certain reserves like oxygen included; if you make a starter these are expended/wasted before you then pitch into the main brew. That said you can make a starter with dried yeast, if you then treat them like wet yeast when it comes to pitching, but the cost and effort of making a starter is quite high given the low cost and convenience of using the dried form as intended, so most people would normally just use more packs if they need more cells.

The issue is confused because some people wrongly refer to rehydrating dried yeast as making a starter; it is a different thing. Rehydrating effectively just wakes the yeast up, preparing them to be pitched, it doesn't grow up their numbers. Its more gentle on the yeast and so best practice to use water to rehydrate, however its more convenient to pitch direct into the fermenter and the differences often aren't outwardly visible which is why people do both.

Its true that an opened pack of dried yeast will potentially not keep as long as a sealed one, but if you can put in it a sealed bag (or something like that) to keep them dry and stop other yeast/infections getting in then IMO they will keep at least as well and probably better than slants.

[Battleaxe]

Kev888 this is possibly the best response I've had since I've started brewing.

Cheers for clearing that up!

I've really enjoyed making a starter though I'm always trying something new so when I do start using liquid yeast I now have some experience with making a starter.

There's always something you could do differently when your brewing!