[ultravista]

I am brewing MoreBeer's Pliny the Elder all-grain kit next week. A local brewer graciously provided me with approximately 20 ounces of fresh WLP001.

A White Labs vial is 35ml or approximately 1.2 ounces of yeast.

How much of this jar would you use for Pliny with an OG of 1.07x?

The entire jar would be a massive over-pitch. I would like to save some for another batch later on down the road.

[Stevie]

Assuming it is a 5 gallon batch, I would use about 3-4 packs worth. So about 4 ounces.

[theDarkSide]

Just entered into Mr Malty and with the default settings it says about 124ml or 4.19oz.  This stuff looks pretty thick so 4 oz. sounds good.

[ultravista]

It's super gloppy and thick.

I was thinking about splitting the rest of it amongst several smaller jars and topping off with distilled water.

Is this a sound plan for storage? Would freezing (without glycol) kill the colony entirely? Would freezing be better or worse than leaving it at refrigerated temperature for months?

[morticaixavier]

you are better off storing under beer than water. the pH and alcohol content of the beer will better protect the yeast from contamination.

I would keep it in the fridge and make a starter from a tablespoon or so or use it up in the next few weeks.

[ultravista]

morticaixavier - my next brew won't be for a few months.

[morticaixavier]

at that point you're better off using a tablespoon or so of the slurry and making a starter. The yeast you pitch into your next batch will be much younger and more vital that way.

[ultravista]

I may just use half of it and save the rest.

[S. cerevisiae]

That slurry contains approximately 1.2 billion cells per milliliter; therefore, I would use roughly 40ml of slurry per gallon of wort in the 1.070 - 1.072 range.

[ultravista]

S. cerevisiae, that's approximately 7.5 ounces.

Let's say I started with a vial of yeast, how big of a single starter would it take to build-up the cell count for a batch this size (1.070)?

Based on your feedback, my paltry 2L starters appear to be woefully inadequate for batches > 1.070.

[a10t2]

That slurry contains approximately 1.2 billion cells per milliliter

Wow, my monitor doesn't have nearly that kind of resolution.

[klickitat jim]

That slurry contains approximately 1.2 billion cells per milliliter

Wow, my monitor doesn't have nearly that kind of resolution.

Time for an upgrade.  Just charge it to the brewery.

[S. cerevisiae]

Wow, my monitor doesn't have nearly that kind of resolution.

I am just making a SWAG based on the color.  The crop appears to be a mixture of break and yeast.  I am being conservative by estimating that the the crop contains approximately 50% yeast cells (the percentage could be higher), which should be around 1.2 billion cells per milliliter.  The only way to know for certain is to count.  However, as I have mentioned before, yeast cultures are like nuclear weapons in that one does not need pin-point accuracy in order to get the job done.  Two hundred milliliters of that stuff should fully attenuate 5 gallons of 1.072 wort without batting an eye.  Heck, 150 milliliters should do the job.

[ultravista]

S. cerevisiae - let's say I started with a vial of yeast, how big of a single starter would it take to build-up the cell count for a batch this size (1.070)?

[S. cerevisiae]

A 2L starter will provide a substantial margin of error for 5-gallons of 1.070 wort.  However, a starter is a waste of time with that much yeast slurry at your disposal.   All you need to do is to pitch 5 to 6 fluid ounces of that stuff.