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Craft Beer & Brewing

Recipe: Opus Aeternum, the Neverending Boil

From South Africa’s Afro Caribbean and Soul Barrel breweries, this hefty barleywine of 17.5 percent ABV is based on a unique, experimental process involving a boil stretched out over six days.

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Photo: Courtesy Afro Caribbean Brewing
Photo: Courtesy Afro Caribbean Brewing

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By boiling for a total of 20 hours over those six days, the brewers achieved 50 percent evaporation before fermenting with a potent, enzyme-enriched yeast strain and aging in a second-use bourbon barrel.

ALL-GRAIN

Batch size: 5 gallons (19 liters)
Brewhouse efficiency: 72%
OG: 1.156 (35.4°P)
FG: 1.048 (12°P)
IBUs: 100+
ABV: 17.5%

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From Grain to Class (Spring 2026)
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From Grain to Class (Spring 2026)
Your guide to classic and cutting-edge techniques for brewing with wheat, fonio, specialty malts, and more.
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