‘Tis the season when craft beer switches from light, summery styles to more holiday, fall-friendly recipes. It should be no surprise when the seasonal crush of Oktoberfest/märzens abruptly yields to spicier brews like stouts, pumpkin ales and winter warmers. Texas may not have much of a winter compared to Northern states but the marketing push persists.
Of particular interest in these pre-Thanksgiving weeks is the pumpkin ale (beer brewed with cooked pumpkin), which can historically be traced back to Colonial America. In times when brewing grains were in precious supply, local vegetables would be added to a recipe as extenders to provide fermentable sugars for yeast cultures while leaving the final product pleasantly palatable. Pumpkins, fall/winter squash and potato varieties proved not only seasonally plentiful but also appealing (at least, not unappealing) to the senses.
Pumpkins (Cucurbita pepo, the oldest cultivated crop in North America) have long been the craft beer favorite for late-seasonal brewing, largely relying on the popularity of pumpkin pie flavors. However, pumpkin flesh itself is fairly light to neutral in flavor, and the flavor elements craved by fans of the beer are associated more with the dessert: cinnamon, nutmeg, clove, ginger, allspice and sugar. One of the more popular North Texas pumpkin beers, Lakewood Brewing‘s Punkel is marketed in this same category yet it contains no pumpkin at all, only spices added to a traditional German ale recipe.
Sweet potatoes are not true tubers but instead are thicker portions of the plant’s modified lateral root systems.
If flavor is the objective and ease of brewing an added bonus, brewers should turn away from the pumpkin and embrace the sweet potato. The American sweet potato (Ipomoea batatas) is a distant relative of the common potato (Solanum spp.) and sometimes mistakenly called a “yam,” although all three of these vegetables are distinctly different species (yams are of African origin). Sweet potatoes have all the positive brewing characteristics of pumpkins but with one very important difference: flavor.
Whereas the pumpkin has around 3.2 grams of sugar per cup, the sweet potato has twice that (sugar being essential for fermentation). Both are about equal in overall nutritional value with sweet potatoes providing more per pound based on their caloric content and density (77% water as opposed to 92% water for pumpkin flesh), making them a more efficient choice in a full-scale production batch. But unlike pumpkins, sweet potatoes are packed with an enzyme called amylase, which breaks down vegetable starches into fermentable sugars. From a brewing perspective, this is a huge functional advantage over the dominant orange gourd, most of which are now grown for ornamental use instead of culinary.
But as mentioned previously, the major advantage sweet potatoes offer over pumpkins is taste. The gentle, semi-sweet flavor of sweet potato comes through more readily when used in brewing than does pumpkin, whose cooked flesh is almost vanishingly mild amid a beer’s malt, hops and any added spices. When brewed well and with a touch of maple syrup—a natural pairing with the sweet potato—the final product can land somewhere on the flavor spectrum reminiscent of the sweet, marshmallow-topped holiday casserole.
Pumpkin and “yam” seasonal beers from North Texas brewers are few this season. Martin House Brewing released a Cuvee Pumpkin Latte last year, and Legal Draft Brewing produced a Roasted Pumpkin Spice Lager just a few years ago. Martin House’s current Half-Baked “Pumpkin Pie Ale” is aged in whiskey casks, which at ABV 12% all but obscures any pumpkin brewing additions. Houston’s Saint Arnold Brewing continues its seasonal pumpkin ale dominance with another release of their annual Pumpkinator (ABV 11.2%) but this heavy hybrid of imperial stout and doppelbock lives alone within its own category.
The most recent seasonal of the sweet potato variety is Armadillo Ale Works Pump Up The Yams (ABV 9%), a self-described “Malt Beverage with Pumpkin, Sweet Potatoes, & Natural Flavors.” Familiar fall elements are still present, with plenty of nutmeg, cinnamon, pecans and maple syrup, but an identifiable sweet potato element does come through. After years of seasonal dominance by overspiced pumpkin ales of many stripes, a good sweet potato beer is a refreshing change of pace.