why not scale down the yeast?

[anteup02]

I have read a bunch of posts on here about scaling down recipes. However I have read more than once to just use an entire pack of yeast and not worry about scaling this down. Why is this? If I'm making 2.5 gal batches does this mean i should not split a pack of yeast and use half in each batch? Thanks!

 

[z987k]

Depends. What is the gravity of the beer?
http://www.mrmalty.com/calc/calc.html

 

[weirdboy]

I assume you are talking about dry yeast packets. It is my personal opinion that once you open the packet, there's no telling how viable the second half of that yeast will be on the next batch. Although, if you are doing two batches on the same day, you'd probably be fine. That also assume you are talking about "normal" beers like an APA, and not anything higher gravity.

If you mean liquid yeast, you are likely already underpitching with a full activator pack or vial and no starter for many 5 gallon batches. For a 2.5 gallon batch pitching a full package is around the right amount for many beers, and still possibly underpitching for high gravity stuff.

 

[anteup02]

yes, i mean dry yeast, and i would be doing it on the same day. And yes, these test batches I am doing are APA.

z987k - thanks a lot for that link, that is very helpful!

 

[Bobby_M]

Sure, if you're doing session gravity beers, go ahead and split the pack. I'd use that second half within a day or two though.

 

[BackAlleyBrewingCo]

Why the hurry to use the remaining yeast right away?

FWIW, I've stored half of a packet of Nottingham in the freezer for a month and didn't notice a difference when I used it.

 

[TipsyDragon]

it depends on the OG of the brew. yes you should scale the yeast. some recipes require 2 smack packs and if you scale it down to a 2.5gal batch then you only need 1 smack pack. to get the correct pitch rate go here.