Parti-Gyle Brewing

Two for One

Parti-gyle brewing produces two or more beers of different strengths from a single mash. The first runnings (highest gravity) make a strong beer; the second runnings (lower gravity) make a session beer. This historical English technique maximizes grain usage and creates variety from a single brew session.

How It Works

During lautering, the first wort collected is highest in sugar concentration. As sparging continues, each subsequent gallon is progressively diluted. In parti-gyle, you split these runnings into separate kettles:

First runnings — OG 1.070-1.100+ depending on grain bill. Suitable for barleywine, old ale, imperial stout, or strong Belgian ale.

Second runnings — OG 1.030-1.045. Suitable for ordinary bitter, mild, small beer, or session pale ale.

Planning the Split

Calculate the total grain bill as if brewing a single strong beer. Then determine where to split the runnings. A common approach:

1. Collect first runnings until you have 3-4 gallons of high-gravity wort
2. Sparge normally, collecting second runnings into a separate kettle
3. Boil each kettle separately with different hop schedules
4. Ferment with different yeast strains if desired

Hop Schedule Variation

The two beers need not have the same hop character. The first runnings might become a malty barleywine with moderate hopping. The second runnings might become a session IPA with aggressive late hops and dry hopping. Same grain backbone, different flavor profiles.

Yeast Variation

Use English ale yeast for the strong beer and American ale yeast for the session beer. Or pitch the same yeast into both for a coherent family of beers. The flexibility is part of the appeal.

Efficiency Considerations

Parti-gyle brewing has lower overall efficiency per gallon than conventional brewing because the first runnings are very concentrated. However, total extract recovery is similar — you are simply distributing it unevenly across two beers.

Historical Context

English breweries commonly used parti-gyle through the 19th century. The terms "strong ale," "common ale," and "small beer" often referred to first, second, and third runnings from the same mash. This system allowed a single brew day to supply beers for different price points and occasions.

Modern Parti-Gyle

Today, parti-gyle is popular among homebrewers who want variety without doubling brew days. A Saturday parti-gyle session produces a strong ale to age and a session beer to drink immediately — two distinctly different beers from one grain bill and one mash.