In 1710, the remains of the Danish fleet returned from the Battle of Køge Bay to Copenhagen. The crews and officers were deeply unhappy, not only because their mission had failed nor even that the flagship Dannebrog had been lost. No, their complaint was that a quarter of the crew had been sick before they even sailed, and many had died of illness at sea before they ever met the Swedes. The admiral blamed the skibsøl—literally, “ship’s beer”—which was an important part of the fleet’s provisions.
The navy’s commissar-general investigated the issue, and he found that throughout the year there had been many examples of skibsøl being found spoiled and returned to the brewers. The returned beer wasn’t merely sour—it was foul. His report was part of a long discussion that had already run for many decades about how to ensure a reliable supply of skibsøl that did not go bad.
People pointed to various causes of the problem: The beer was too weak, the wood for the casks was too fresh, or the casks had been washed in seawater, and so on.