4.25oz Wyeast Packs?

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Cpt_Kirks

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I brew a lot of 9 gallon batches (3 gallons for one keg, 5 gallons for another, about a gallon of waste).

Are the Wyeast 4.25oz packs big enough two fermenters if divided between them?
 
Is this a serious question? The Activators aren't even really big enough for one 5 gallon fermenter, let alone two.
 
we are talking about activator packs right ? they say its enough for 5 gallons but I always make a starter specially if its a higher gravity beer.Go to Mr.malty it will give the proper pitch rate
 
Let's explore the math, shall we?

The industry standard pitching rate for ales is 75 millions cells/mL/°P

An Activator pack contains, at the very peak of freshness, 100 billion cells. However, because you can't control the transport conditions between manufacture and when it reaches your hands, this number is far from reality.

Assuming a 5 gallon batch of 1.050 wort:

75,000,000 x 19,000 (rounded slightly to make the numbers easier) x 12.5°P =

Roughly 178 billion cells necessary to properly inoculate the wort.

You're underpitching by a fairly significant margin, even more so if you're trying to split a single smackpack between two fermenters.
 
The 4.25 oz packs are the Activator (says so right in the description on Midwest ;)), but the fact of the matter remains that there's not enough yeast to direct pitch into 5 gallons of anything higher than 1.028 OG, following established pitching rate guidelines.

Yes, I know Wyeast and White Labs both advertise their liquid yeast as being directly pitchable. However, the fine print is that those directions are dependent on pitching at 70° until visible signs of fermentation are noticed and then dropping down to your target fermentation temperature.
 
OK, that is what I needed to know.

Looks like I will need a starter. I wonder if I should make one large starter, and split it between fermenters, or two starters?
 
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