We tend to think about regional cuisines in terms of flavor, texture, or signature preparation; sometimes it’s a specific combination of ingredients — think Basque piperade, or Old Bay Seasoning in Maryland. In Sichuan, it’s a sensation: the numbing, tickling heat of the region’s beloved peppercorn, zanthoxylum. (Calling it a peppercorn is actually an entrenched misnomer: it’s closer to the citrus family than to hot chilis.)
At Roads and Kingdoms, Taylor Holliday, a purveyor of Sichuan ingredients, takes readers along the peppercorn’s path from rural farms and Chengdu markets to the USDA bureaucracy that has made it extremely difficult to bring to the States. At its core, though, this is an ode to a spice that etches itself onto your memory within seconds of your first taste.
Even more than other spices, endowed by evolution with defensive odors and tastes, Sichuan pepper seems designed not to be eaten. Once you get past the thorns, the taste of a fresh or freshly dried berry leaves your mouth, tongue, and lips buzzing and numb for several minutes. It is literally electric: The active ingredient, sanshool, causes a vibration on the lips measured at 50 hertz, the same frequency as the power grid in most parts of the world, according to a 2013 study at University College London.
In late June, the Sichuan pepper harvest in Qingxi, the Hanyuan town at the heart of pepper production, was still at least a couple months away, generally “during the seventh lunar month,” according to Di. But the berries getting direct sun are already plump and red and releasing some very potent, intensely numbing oil once you bite into them or squeeze the little bumps covering the surface of the peppercorns. After the berry clumps are painstakingly harvested, the farmers sell them to a processor who dries them until the little pods open, releasing their unpleasantly brittle black seeds, at which point their shape resembles a flower, earning them the name hua jiao, or flower pepper, in Sichuan dialect.
The best hua jiao are fully open with few seeds or stray twigs, and certainly no thorns—though some have been known to sneak through in lower-quality product, which is one reason premium peppercorns are not only picked but also cleaned and sorted by hand. They deliver not only the tingly sensation prized in Sichuan food, often paired as a one-two punch with chili peppers, but also a strong citrusy perfume and taste that adds intrigue to the heat. Outsiders think of Sichuan food as spicy hot, or la, but the more prevalent and unique characteristic of the cuisine is ma, the citrus tingle of Sichuan pepper. The combination of the two, mala, is what we typically think of as Sichuan flavor.