Yeast re-pitching

[wailingguitar]

Without getting into the obvious arena of cell-counts, etc., looking for a ball park of what people typically see in the actual volume/bbl on repitched yeast. I am specifically interested in S04, but am curious about other strains as well. Any info would be much appreciated.

[CharlosCarlies]

By volume do you mean in slurry harvested? If so, we use US-05 for most of our ales which obviously doesn't floc as well; however, we're generally pulling ~150-160 lbs from a 40 BBL batch. For the US-05, we're soft-crashing before dry-hop so the slurry is a little thinner and usually damn near overflows our 22 gallon brinks. In the case of our lagers (34/70) where we can actually completely crash it first, we're getting a similar weight in what I would guess is ~17-18 gallons.

Hope I read your question correctly and could be at least somewhat helpful!

Edit: And if you're talking about actually re-pitching said slurry, we usually end up using 2-3 lbs/BBL on our ales and 4-6 on our lagers. I remember reading those rules of thumb somewhere and they ended up being pretty accurate after actually doing cell counts.

[wailingguitar]

By volume do you mean in slurry harvested? If so, we use US-05 for most of our ales which obviously doesn't floc as well; however, we're generally pulling ~150-160 lbs from a 40 BBL batch. For the US-05, we're soft-crashing before dry-hop so the slurry is a little thinner and usually damn near overflows our 22 gallon brinks. In the case of our lagers (34/70) where we can actually completely crash it first, we're getting a similar weight in what I would guess is ~17-18 gallons.

Hope I read your question correctly and could be at least somewhat helpful!

Edit: And if you're talking about actually re-pitching said slurry, we usually end up using 2-3 lbs/BBL on our ales and 4-6 on our lagers. I remember reading those rules of thumb somewhere and they ended up being pretty accurate after actually doing cell counts.

Thanks. So if I understood correctly, on a well crashed beer you are typically using a bit less than 1/2 gallon of slurry/barrel to get the pitching rate you are looking for?

[Matt@Bauhaus]

Thanks. So if I understood correctly, on a well crashed beer you are typically using a bit less than 1/2 gallon of slurry/barrel to get the pitching rate you are looking for?

There's a great article in one of the MBAA technical quarterly publications that discusses serial repitching by mass for smaller breweries. You'll need to be a member to view it: http://www.mbaa.com/publications/tq/...-4-1228-01.pdf

Basically, the article concludes that for a normal gravity ale (<16ºP) a pitching rate of 1 kg per bbl will result in "ideal" cell counts. For lagers of similar gravity, a pitching rate of 2 kg per bbl is ideal. The conclusion is actually more nuanced than this, but we follow these rules of thumb in our brewery, and we almost never have issues with lag time or reaching full attenuation. Occasionally, we'll break out the microscope and hemacytometer to check our counts, but it usually just confirms what we suspect: our pitch rates are in the "ideal" range.

[Bainbridge]

We find weight to be much easier than volume. 1.5 lbs/bbl if it is very fresh or especially thick, 2lbs if it's older (up to two weeks in the brink) or thinner (say harvested off an uncrashed IPA before dryhopping.) We've been doing 3 on our kolsch but I'm experimenting with different weights and temps on that one right now. Used to do 3lbs and 58 degrees. Just pitched 1.5 of very fresh on it at 65 yesterday and it took off just fine. We'll see what flavor changes there are.

[Junkyard]

We've found about 1500 ml per barrel works pretty well for pitchig most slurries into wort under 1.060