whiskey mushroom — sometimes called stills fungus, rum fungus, or warehouse staining fungus — is a black fungus with the scientific name Baudoinia compniacensis. Although the fungus is literally black in color, it is not the same as black mold, Stachybotryswhich can cause significant health problems and damage to infrastructure.
Here’s what happens: After the whiskey is distilled, it’s kept in barrels in a warehouse during its aging process. The length of distillation time varies, but during the process, approximately 2 to 5 percent of the alcohol evaporates. Depending on the amount of alcohol being processed, it can add up to 200 to 1,000 tons (181 to 907 metric tons) of ethanol emissions every year.
The emissions are poetically known as the “angel’s share”, but there is evidence to suggest that the vapors do not reach heaven. When ethanol combines with moisture in the air, the result is a type of fungus that feeds on the sugar in ethanol: the whiskey fungus. Like any other fungus, it attaches itself to almost anything, including buildings, trees, cars, and outdoor furniture.