Cracking the Codes of Centuries-old Brewing Recipes
Cornell adds that brewers throughout Britain would have heard of the scandalous activities of two brewers from Austria and Germany, Anton Dreher and Gabriel Sedlmayr. In the 1820s and ’30s they made extensive visits to other countries to study new brewing techniques. They were warmly greeted in Burton-on-Trent, where Bass presented them with saccharometers to measure the fermentable sugars present in wort, the sugary extract that’s the first stage of the brewing process.
The visitors from Europe repaid this kindness with acts of industrial espionage. They used thermometers to secretly measure brewing temperatures, and they had hollowed-out walking sticks with hidden valves in which they kept samples of beer and wort for later analysis. They wrote home saying that while they had been welcomed in one brewery “We stole as much as we could.” Sedlmayr added: “It always surprises me that we can get away with these thefts without being beaten up.” Dreher and Sedlmayr returned to Vienna and Munich to launch commercial lager beers that started to eat in to the sales of exported pale ale from Burton. It’s little wonder that brewers were keen to protect their recipes.
In Faversham, the brewing ledgers discovered by John Owen in 2008 covered the years 1799 to 1818. They are the oldest surviving recipes at the brewery. They provide a record of brewing days, the “quarters” of malt and hops used and the amounts of strong ale, XX, and table beer, X, brewed—except this information is written in code. Quarters are an old form of measurement, later replaced by pounds. The brewery was producing some 71,000 barrels of beer a year in that period.
On May 19, 1813, the brewer in charge was Henry Shepherd Jr. and his codes—typical of those used throughout this period—appear under the date in the first column and use the letters GBX, JBX and SPX. Some pages are heavily crosshatched in ink—presumably when brewing had finished—to obliterate information about ingredients and temperatures.
John Owen and Stewart Main spent months of diligent work deciphering the codes. They did this by comparing the ledgers with more recent brewing books from the later 19th and early 20th centuries, enabling them to establish building blocks to re-create beers from the old logs. There was consistency throughout the period in the supply of raw materials, with hops bought from local farmers and grain imported via Faversham harbor from Norfolk in eastern England, the country’s main barley-growing region.
Cracking the codes was a matter of trial and error. It was immediately clear to Main and Owen that the letters GBX, JBX and SPX referred to quantities and types of malt and hops used. Working out the ratios was not easy, and at first Main came up with recipes with more hops than malt. He had to turn the figures on their head. A further problem was the terse manner in which malt was designated at the time: merely “pale malt” and “dark malt,” with no indication of the types of dark malt used and their color. But Main was able to compare the logs with later ones from the 20th century and build up a profile of the likely materials used. It was not difficult to pinpoint the hops, as Fuggles and Goldings were the most widely used varieties at the time.
Roger Protz
Roger Protz is a British beer writer and edits the annual Good Beer Guide. He is the author of more than 20 books, including 300 Beers to Try Before You Die. He has received a Lifetime Achievement Award from the British Guild of Beer Writers and has twice been voted Drink Writer of the Year in the Glenfiddich Awards. More at protzonbeer.co.uk.
