Liquid Yeast

[rwh]

One question. How long will the stubbies of yeast last stored like this in the fridge? (@ about 3-4c i guess)

A long time, especially if you start with a high population, and you make a starter afterwards. So I would suspect anywhere up to a couple of years. If you want to go longer than that, look in to using glycerin to suspend and freeze the yeast.

I must admit that I vary that method a little these days; I use 50mL tubes with caps that I got of eBay instead of stubbies, and I generally do 2 or 3 starter generations before I split and refrigerate (to boost the population even further). I'm at the point where I can almost pitch the contents of a tube directly to a 23L batch, tho in practice I normally do still make a starter. I also use scientific glassware on a stir plate. The stir plate boosts population by up to 3x according to what I've read.

Oh, and I also tend to cold pitch.

[Elbow]

Anyone know where you can pick up plastic or glass test tubes in Melbourne? I'm looking to split a Wyeast smackpack this weekend if possible.

[Elbow]

Ok, I managed to get 6 test tubes.

I decanted an un-smacked Wyeast (Denny's favourite) into the six test tubes and put five of them in the fridge for later use (as per Ross's method on page 2). For the last test tube, I had a go at making a starter using 500ml water and 50g of dried malt, plus the nutrient package from inside the smack pack. This fermented well, so I then stepped up to 1 litre and 100g of DME. This is also going well after 24 hours.
My question is: Because I used a sixth of the smack pack (probably around 20ml), will I need to step up to a very large starter? Or can I just pitch once this current 1 litre starter has reached high krausen?

Sorry for the questions, it's my first go at a starter.

[warra48]

My question is: Because I used a sixth of the smack pack (probably around 20ml), will I need to step up to a very large starter? Or can I just pitch once this current 1 litre starter has reached high krausen?
Sorry for the questions, it's my first go at a starter.

To the best of my knowledge, you double the cell count at each step in normal circumstances.
So, if you started with 1/6, you should have 2/6 after step one, and 4/6 after step two.

Personally, I'd step it up by doubling the size of your starter again.

In my personal view, a Wyeast pack is designed to supposed to inoculate 5 US gallons (19 litres) in a single brew, provided the pack is fully viable.
To inoculate a 23 litre brew, I think you really need more than a standard pack.
That's why I always use a starter, even when using a full pack for a single brew.

[Elbow]

HI Warra,

Thanks for that. Yes, I stepped it up again to a 2 litre (200g LDME) starter which is fermenting at the moment. I think I might pitch this one as I've already changed starter bottles once as my original was only 1 litre. Don't want to tempt infection by opening up the bottle for anything other than tipping off the excess beer and pitching into the wort.

I think I read somewhere (Mr Malty) that said a smaller amount of healthy viable yeast is better than a bigger amount of stressed stuff. Then again, they also said you need a ridiculous amount of liquid yeast for starters, so who knows!

I'll be pitching this one into a Grain and Grape wort kit to make an American pale ale up to about 20 litres, so hopefully all should be good.