Andrew Holzhauer was stocking bottles of a beer 4 years in the making into the taproom cooler at Funk Factory Geuzeria (Madison, Wisconsin) a few months ago when he and a colleague decided to open and split a bottle.
The beer, The Last Four Winters in Wisconsin, is a blend of 1-, 2-, and 3-year lambic-style ale that had bottle conditioned for 15 months before its release. The release was actually in two stages. The first happened in December 2018 during a formal celebration where customers left with cage-and-cork-topped 750ml bottles. Then, a smaller run was put into 375ml bottles, capped, and sold in the tasting room. Over the course of a few months, the cooler supply was replenished with the stock from the storeroom.
The small bottle that Holzhauer, the head of operations at the brewery, opened showed signs of acetaldehyde, “a touch of Windex, not super acidic but not something that was present in the beer to begin with. And this surprised me because the beer was still fully carbonated, but there must have been some kind of oxygen ingress.”