Brewers aren\u2019t bashful about playing in winemakers\u2019 sandbox. They\u2019ve infused IPAs with Syrah must, seasoned saisons in Chardonnay casks and fermented beer with Champagne yeast. Now, they\u2019ve filled brewhouses with massive wine-aging vats called foudres (pronounced FOOD-ers).\r\n\r\nTraditionally, some winemakers (especially those in France\u2019s Rh\u00f4ne Valley) have favored the colossal wooden containers that impart less oak flavor because of their large surface area. For beer makers, though, foudres are storehouses for cultivated colonies of Brettanomyces yeast and souring bacteria. The vessels allow brewers to make bigger batches, so they can craft more consistent wild creations, drawing off fermented liquid and refilling with fresh beer as needed.\r\n\r\nCharleston, South Carolina-based Revelry Brewing recently opened a facility, dubbed the Hold, dedicated to aging beer in foudres and barrels.\r\n\r\n\u201cThe product in the foudre is the steak, and the beers in my smaller barrels are my salt and pepper,\u201d says Ryan Coker, the co-founder and brewer.\r\n\r\n\r\n\r\nNationwide, you\u2019ll notice numerous brewers sourcing foudres for flavorful experiments. (They\u2019re buying them secondhand from wineries or new from makers such as Missouri\u2019s Foeder Crafters of America.) In Colorado, New Belgium\u2019s foudres are crucial to sours such as La Folie, which ages for up to three years, while Denver\u2019s Crooked Stave uses foudres to fashion rustic, vinous farmhouse ales.\r\n\r\nOf course, not every brewery uses foudres for sour beer. In Brooklyn, Threes Brewing makes Kicking and Screaming, a foudre-fermented pilsner with a marshmallow note. Meanwhile, the Illinois-based Two Brothers Artisan Brewing has made several foudre-aged IPAs, like the pleasantly oaky Resistance.\r\n\r\nNo matter the style, sometimes the tallest oaks produce the tastiest beer.\r\nRecommended Beers\r\nNew Belgium Brewing Company Sour Saison\r\nThe Coloradans\u2019 veritable foudre forest produces masterpieces like this French-inspired sipper. The blend of foudre-seasoned sour golden ale and fizzy farmhouse ale is a marriage of lemon pucker and fresh-baked bread.\r\nSweetWater Brewing Co. Cambium \r\nWith its Woodlands project, the Georgia brewery uses foudres and wild microbes to produce beers like this fizzy crowd-pleaser, available in late January. It\u2019s a tingly tango of stone fruit and funk.\r\nBruery Terreux Frederick H.\u00a0\r\nThe Bruery\u2019s wild-focused spinoff uses towering foudres that contain nearly 8,000 gallons of beer like Frederick H. The German-inspired Berliner Weisse is an earthy refresher with enlivening acidity that\u2019s not unlike a lemon spritz.\r\nAllagash Brewing Company Hive 56\r\nTo make Hive 56, Allagash brews a dark ale and ages it in foudres for 18 months alongside a strain of wild yeast and honey from the brewer\u2019s beehives. The result: a tart tangle of roast, dark chocolate, raspberries and tropical fruit.