How to Perform a Parti-Gyle

So, what is a parti-gyle? What is it good for? Absolutely one main thing—you get a few beers from one batch. This can result in cheaper costs, different beers, and general merriment. This is performed by running off the first runnings from a mash, making a beer from that, and then adding more mash water and getting lower abv beer from the second runnings. Sometimes a third and even a fourth beer can extracted.

This was done a lot back the ye olde days. The brewers didn’t really know mash chemistry, nor have thermometers (until the 1760s), so they created weirdo ways to brew, and parti-gyle was one. In parti-gyle brewing, a brewery would pack the mash tun full of malt and then draw off multiple worts (“gyles”). In popular understanding of the technique, the first wort would make a strong beer and the second would make a “small” beer.

Nowadays it’s performed largely on the homebrew scale. There are however a few breweries who are doing parti-gyles, one such brewery is Fuller’s, who make a few different beers from one batch.

But how does one figure this out Jason? How do you know how much grain to start with? Don’t worry, I go you fam. Figuring out how much grain will be needed takes some easy math. I will be referencing an article by Terry Foster, where he breaks this all down by the use of gravity points (I love articles). I will say the only confusing thing for me in the article is he kept saying “original gravity points” when referring to gravity points, which would mean post-boil gravity, but how could you go off that when you are formulating recipes? It’s more important to want pre-boil gravities. I think (assume) he is referring to pre-boil gravities when he says “OG”, so that’s what I went off of.

I will break this down for the batch I will be brewing in this post:

I want 3.75 gallons total pre-boil, collecting 1.5 gallons with the first runnings at 1.060 (pre-boil), and 2.25 gallons for the second runnings at 1.025 (pre-boil). Taking just the gravity points, you can calculate the first part as such:

First runoff = 1.5 x 60 = 90
Second runoff = 2.25 x 25 = 56.25
Total points = 90 + 56.25 = 146.25

Assuming with 65% extract efficiency that 1 lb. of pale malt in 1 gallon of water yields a wort of SG 1.024:

Total malt required = 146.25 ÷ 24 = 6 lbs.

I was doubtful of this because of the lack of clarity between OG and pre-boil starting gravity, so I did some digging and found this calculator: I love calculators. According the calculator, with 6 lbs of grain my starting gravity would be closer to 1.070, not 1.060. So I was torn on what to do, which for me usually results in just going for it and figuring it out on the brew day, which I did.

To have some fun with this, I took the first runoff and made a barleywine, and my friend Rob took the second runoff and made a white IPA with bitter orange peel. We actually did this in the past two different times (Take to the first timeactually I want to go to the second time).

Two very different beers from the same batch. My kind of weird!

Brew day:


Full Batch Size: 3 Gallons
OG: 1.050
SRM: 4
Boil Time: 60 Min (just what

60 Min @ 150F

Grain profile:
(100%) – 2-Row

60 Min @ 150F

First runoff – barleywine (Jason’s):

Batch size: 1 gallon
OG: 1.097 (from 1.057)
Boil Time: 60 Min
IBUs: 90

(66 IBUs) Chinook (14% AA) @ 60 min
(24 IBUs) Chinook (14% AA) @ 10 min


Second runoff – “white” IPA (Rob’s):

Batch size: 1 gallon
OG: 1.061 (from 1.026)
Boil Time: 60 Min
IBUs: 70

4 oz DME @ 60 min
Steeped Crystal 20L to get the SRM to 7.5 @ 60 min
(23 IBUs) Cascade (8.3% AA) @ 60 min
(33 IBUs) Citra (12% AA) @ 60 min
(14 IBUs) Cascade (12% AA) @ 20 min
Bitter orange peel @ 5 min
.5 oz Centennial @ 0 Min

Dry hop:
.25 oz Bitter orange peel @ 7 days
.5 oz Centennial @ 7 days


Here’s what went down:

Brew day 7/14/18

Ground 6 lbs of 2-row, mashed in with 2.5 gallons of water (grist ratio was 1.5 its per lb of grain).

First runnings:

Collected 1.5 gallons at 1.073! The online calculator was right. I may have been able to collect 1.75 gallons pre-boil, but I already was over what I was planning on, so some got left behind for the second running. Thankfully I was prepared and had extra distilled water, which I used to dilute down to 2 gallons at 1.057. I took off half a gallon and got to my starting 1.5 gallons.

Second runnings:

Mashed in with 2.25 gallons, and collected 2.25 gallons at 1.026! Nailed it. I don’t know that we would have hit this had I not left some wort behind, but a further experiment is needed. Rob only wanted a gallon of the beer, so we combined his extra, with some of the half gallon extra of my first runoff and got a sour going (I was going to do this anyway for the record, hence a 3 gallon starting planned batch).

8/2/18: Bottled the white IPA.

8/12/18: Bottled the barleywine.

9/5/18 Tasting:

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