The American whiskey industry is in the midst of an expansion going into its third decade. One side effect of that growth is increased prevalence of Baudoinia compniacensis, the whiskey fungus, in the vicinity of whiskey maturation facilities.
Today, virtually all major American whiskey producers are operating at capacity. To grow, they must enlarge their distilleries, or build new ones, and build many new maturation facilities, either at the distilleries or remote locations.
Old house and cognac cellars blackened by ‘the angel’s share’ (Baudoinia compniacensis), i. e. alcohol vapors, Jarnac, Charente, France. (image via JLPC / Wikimedia Commons / CC BY-SA 3.0)
Distilled spirits have been known and consumed since at least the 12th century, maybe longer, but the deliberate aging of spirits in oak barrels didn’t become routine until the 17th century, beginning in France. It took a few steps to get there.
Step one: Merchants representing vintners in southwestern France began to sell wine in England in the 13th century. The trade continued and grew in the centuries that followed, with Holland and other Northern European countries added to the customer list.
Step two: Because these voyages were long, wine sometimes spoiled along the way. That was bad for business, so in the early 15th century merchants began to distill wine as a form of preservation. As a bonus, distilled wine was more concentrated, which improved shipping efficiency. They called it ‘burnt wine’ (brandwijn in Dutch). When it reached its destination, the ‘brandy’ was reconstituted with water and sold as wine.
Before you say, “that’s not how it works,” remember that the product in demand was alcohol. The reconstituted brandy had roughly the same alcohol content as wine, and alcohol is what people were buying.
Step three: Throughout history, alcohol merchants have been assiduous about personally testing the quality of their products. Although no deliberate aging was done during this period, merchants noticed that the liquid tasted better after shipment, and correctly assumed that was because of the oak barrels in which it was stored.
In time, people began to drink the distilled product straight, with little or no added water. It was called either ‘brandy’ or ‘eau de vie,’ which means ‘water of life’ in French. Today, those terms are used to differentiate between aged (brandy) and un-aged (eau de vie) fruit spirits.
By the 17th century, merchants in the town of Cognac were buying new distillate from area producers to hold in barrels until the desired taste was achieved. Time in wood created a more desirable and, thus, more profitable product. As barrel inventories grew, the merchants experimented with different aging durations and blending techniques, creating in time the very exclusive brandy known as Cognac.
Initially, aging barrels were stored wherever space could be found, including the attics of homes. Eventually it became necessary to build aging warehouses, and inventories grew to thousands, then hundreds of thousands of barrels. As the practice of barrel-aging spirits spread to Scotland, Ireland, and eventually North America, so did the practice of storing barrels in large warehouses built for that purpose.
Through experience, it was learned that aging spirit needs to ‘breathe.’ In Kentucky and Tennessee, that means warehouses tend to be flimsy—just a thin metal skin over a wooden frame—and full of windows to promote air circulation. Some warehouses have fans.
Although these conditions encourage evaporation, the improvement in taste compensates for the loss of volume. In Cognac, they gave the lost liquid a romantic name, “the angels’ share.”
Since aging began, distillers have known there is ethanol vapor in the air around aging warehouses. To most people, it is a pleasant aroma. As many remark, “it smells like prosperity.”
In the 1870s, a Cognac pharmacist named Antonin Baudoin was the first to describe and analyze the “dark, cryptogamic plant” he observed growing near brandy maturation facilities on masonry walls, tile roofs, and all kinds of wood surfaces, including live trees. Was it fungus or blue-green alga? In 1881, the plant was definitively classified as a fungus and named Torula compniacensis, meaning ‘the torula from Cognac.’ ‘Torula,’ a genus name no longer used, means ‘little rounded thing.’ Locals called it ‘la torule.’
After that, there is little in scientific literature about the fungus until the 1960s, then nothing again until the late 1990s, when the public first became widely aware of sickness and death caused by toxic molds in water-damaged buildings. Suddenly, mold wasn’t something you occasionally had to wipe off your shower curtains. It could kill you.
NEXT TIME: Heightened mold fears coincide with bourbon’s revival.
Charles K. Cowdery is an internationally renowned whiskey writer, specializing in American whiskey. He is a Kentucky Colonel (Patton, 206) and a member of the Kentucky Bourbon Hall of Fame (2009). He is the author of multiple bourbon books, including Bourbon, Strange: Surprising Stories of American Whiskey, and is a...