Wander Brewing’s new coolship (an anglicized term from the Dutch/Flemish word, koelschip) may not be the sexiest-looking piece of equipment in the brewery, but it’s arguably the most romantic. This large, shallow and open stainless steel vessel will be used to make spontaneously fermented ales, similar to how they’re made by Lambic breweries in Belgium and, as of recent years, a handful of breweries in America.
Wander’s coolship was designed to hold a full, 20- to 25-barrel batch of beer. After the kettle boil, the hot wort will be pumped into the open tank, where it will be allowed to cool down overnight. Essentially, a coolship is an inefficient heat exchanger that is used to slowly chill wort while capturing airborne yeast and bacteria. Exposed to the open air, the wort will become inoculated by wild yeasts (including various strains of Saccharomyces and Brettanomyces) and bacteria (including various strains of Lactobacillus and Pediococcus), and then it will be pumped into barrels where it will begin to slowly ferment.
Some Washington breweries have dabbled in spontaneous ales using ramped-up cultures, small makeshift coolships and barrels, but Wander’s coolship just might be the first of its kind to be used in Washington.