Black Flannel Academy

Pre-Prohibition Porter

bottom-fermented · top-fermented

A historical American adaptation of English Porter by German immigrants using American ingredients, including adjuncts.

Color

20 – 30 SRM

Bitterness

20 – 30 IBU

Alcohol

4.5 – 6.0% ABV

Sweetness

Bitterness ranges from medium-low to moderate, with balance typically even between malt and hops and a moderately dry finish.

Balance

Bitterness ranges from medium-low to moderate, with balance typically even between malt and hops and a moderately dry finish.

History

Historical Development

Commercially brewed in Philadelphia during the revolutionary period as an adaptation of English beer. It evolved as German immigrants introduced lager methods during the late 1800s. Prohibition largely eliminated domestic porter brewing except in select northeastern and mid-Atlantic regions.

Modern Evolution

Classic characteristics

Appearance

Medium to dark brown, occasionally nearly black, with ruby or mahogany reflections. Maintains clarity with a persistent light to medium tan head.

Aroma

Grainy malt notes with subtle chocolate, caramel, biscuit, burnt sugar, and licorice undertones. Low hop aroma, with corn or DMS acceptable at restrained levels and minimal esters.

Flavor

Moderate grainy-bready malt flavor featuring low levels of chocolate, burnt malt, caramel, and similar notes. Bitterness ranges from medium-low to moderate, with balance typically even between malt and hops and a moderately dry finish.

Mouthfeel

Medium-light to medium body with moderate carbonation. Low to moderate creaminess may be present, potentially accompanied by slight dark malt astringency.

Flavor Profile Deep Dive

Service notes

BJCP designation

Overall Impression: A historical American adaptation of English Porter by German immigrants using American ingredients, including adjuncts.

Comments: Also known as Pennsylvania or East Coast Porter. This style specifically excludes colonial-era products.

Style Comparison: Smoother and less hoppy-bitter than modern American Porter, less caramelly than English versions, and exhibits more adjunct or lager character. Greater bitterness and roast than International Dark Lager.

Vital Statistics: OG: 1.046 – 1.060 | FG: 1.010 – 1.016 | IBUs: 20 – 30 | SRM: 20 – 30 | ABV: 4.5 – 6.0%

Source: BJCP 2021 Style Guidelines, bjcp.org, retrieved 2026-09-13. Vital statistics are as published; descriptive text is condensed from the published guideline.

Brewers Association designation

Style comparison

Similar Styles

Smoother and less hoppy-bitter than modern American Porter, less caramelly than English versions, and exhibits more adjunct or lager character. Greater bitterness and roast than International Dark Lager.

Ingredients

Grain Bill

Two-row or six-row malt forms the base, with low percentages of dark malts including black, chocolate, and brown varieties. Adjuncts are acceptable, including corn, brewers licorice, molasses, and porterine. Either lager or ale yeast, along with traditional American or German hops.