Splitting a Larger mash into 4 Separate Boils/Fermenters

Hey guys,

I want to do 4 * 1 gallon test batches (BIAB) swapping out several grains and hops. All of the batches share two ingredients:

• Maris Otter
• Cara-Pils

My question is, could I mash these two and then steep the additional grains as I would for specialty grains in an extract recipe when I do my 4 separate boils? Or would I be missing a lot of body? I would imagine that the body I would be getting would not be from these low volumes/weights of grains, but mostly from the base malts. Here are my recipes (all mash at 158, all ferment on WY1187):

Sweet English Mild with Black Patent

• 1 lbs Pale Malt, Maris Otter (3.0 SRM) Grain 1 64.5 %
• 2.4 oz Cara-Pils/Dextrine (2.0 SRM) Grain 2 9.7 %
• 1.6 oz Black (Patent) Malt (500.0 SRM) Grain 3 6.5 %
• 1.6 oz Caramel/Crystal Malt - 60L (60.0 SRM) Grain 4 6.5 %
• 3.2 oz Molasses (80.0 SRM) Sugar 6 12.9 %
• 0.15 oz Goldings, East Kent [5.00 %] - First Wort 60.0 min Hop 5 10.1 IBUs
• 0.15 oz Goldings, East Kent [5.00 %] - Boil 30.0 min Hop 7 7.1 IBUs
• 0.2 pkg Ringwood Ale (Wyeast Labs #1187) [124.21 ml] Yeast 8 -

Sweet English Mild with Cara 120L
Same as above, replace Black Patent with Cara 120L

Sweet English Mild with 120/Black
Same as above with 0.8 oz C120L and 0.8 oz Black Patent

Sweet English Mild with 120/Black and Alternate Hop Schedule
Same as above with the following hop schedule:

• 0.15 oz Goldings, East Kent [5.00 %] - First Wort 60.0 min Hop 6 10.1 IBUs
• 0.08 oz Goldings, East Kent [5.00 %] - Boil 45.0 min Hop 8 4.2 IBUs
• 0.08 oz Goldings, East Kent [5.00 %] - Boil 30.0 min Hop 9 3.5 IBUs
• 0.20 oz Goldings, East Kent [5.00 %] - Boil 0.0 min Hop 10 0.0 IBUs

Thanks for any responses,
Mark

EDIT: These are all scaled recipes, obviously... Original is here:

• 5 lbs Pale Malt, Maris Otter (3.0 SRM) Grain 1 64.5 %
• 12.0 oz Cara-Pils/Dextrine (2.0 SRM) Grain 2 9.7 %
• 8.0 oz Caramel/Crystal Malt - 60L (60.0 SRM) Grain 3 6.5 %
• 4.0 oz Black (Patent) Malt (500.0 SRM) Grain 4 3.2 %
• 4.0 oz Caramel/Crystal Malt -120L (120.0 SRM) Grain 5 3.2 %
• 1 lbs Molasses (80.0 SRM) Sugar 7 12.9 %
• 0.50 oz Goldings, East Kent [5.00 %] - First Wort 60.0 min Hop 6 10.1 IBUs
• 0.50 oz Goldings, East Kent [5.00 %] - Boil 30.0 min Hop 8 7.1 IBUs
• 1.0 pkg Ringwood Ale (Wyeast Labs #1187) [124.21 ml] Yeast 9 -

I don't see why it wouldn't work. I don't think you'll miss anything in body that you couldn't make up elsewhere, considering you're mashing pretty high at 158 (I'd try 154 or so).
You might try a parti-gyle mash procedure. Where you have a base mash and then once you've run off (or collected) 1/3 you can then add back some black patent malt (at this point capping with it) and then collect a second batch.
I believe all grain recipes get 2 gallons of high gravity and 5 of a lower.

One thing I'm concerned about is that in beersmith, each 1 gallon batch requires 3.5 gallons of preboil volume to be collected. The original recipe mash has a total water required of 8.2 gallons. The math just doesn't add up at that point. I might have to mash separately for all of these batches.

I have to ask if the last recipe is the original, where'd the last pound of MO go? maybe that is the source of discrepancy with preboil water volumes.
When I BIAB I'm usually brewing partial mash I know theres a good thread on here about the specifics of it. And I've never tried spliting that many batches. Personally I'll reuse yeast from a fermenter and/or siphon to a separate carboy to blend or split batches (makes great black and tans).
If it were me I'd brew 2 gallon batches separately, then I could Isolate the entire batch and also play around with boil time, mash temp, decoctions even.

mavandeh said:

One thing I'm concerned about is that in beersmith, each 1 gallon batch requires 3.5 gallons of preboil volume to be collected. The original recipe mash has a total water required of 8.2 gallons. The math just doesn't add up at that point. I might have to mash separately for all of these batches.

Click to expand...

Why do you need 3.5 gallons of preboil volume? If you boil off 1 gallon an hour, start with 2.25 gallons.

Yooper said:

Why do you need 3.5 gallons of preboil volume? If you boil off 1 gallon an hour, start with 2.25 gallons.

Click to expand...

Late reply: I probably meant strike water volume. I would assume that beersmith is calculating loss due to grain absorption of water.

Haven't yet gotten to brew these. Picking up some one gallon growlers as soon as I can justify the small expense. Uncle Sam and the AAMC took all my money.