The town of Lugu lies in a narrow valley at the confluence of the Anning and Sunshui rivers in Mianning County, southern Sichuan. Politicians and armies have fought for control of this area since ancient times. Lugu’s subtropical climate makes it particularly suited for growing soy, and fermented tofu (made from a local variety of non-GMO soybeans) is an important part of the local cuisine.
To make fermented tofu, soybeans are soaked, ground, and boiled three times in an iron pot to obtain a milky liquid. The remains of the soy plants are used as fuel for the woodstove that heats the pot. After each boiling, the liquid is filtered through a cotton cloth in order to remove any sediment. Gypsum is used as a coagulant to turn the liquid into tofu, which is then cut into cubes and sun dried. Once sufficiently dry, the tofu is ready for the first fermentation: The blocks are placed on a layer of straw on wooden racks and left for 10-12 days. The straw contains spores of the various molds responsible for the fermentation. After the first fermentation, the tofu blocks are sealed in large ceramic jars along with a brine of rice wine, salt, chili powder, and Sichuan pepper. The jars are stored in special adobe buildings for about six months, during which time the tofu and brine ferment. The regional microclimate and the conditions inside the adobe storage buildings affect the fermentation.
Cubes of Lugu fermented tofu weigh 40-50 grams each. They have a reddish surface and a white or yellowish interior. Their texture is firm but tender, and they are slightly spicy. Both the solid tofu and the brine are consumed, usually in small amounts as a condiment, due to their strong flavor. The brine is used to season roasted peppers or rice with egg. Many families in Lugu continue to produce this traditional fermented tofu, both for household consumption and to sell. Five to ten thousand jars are produced each year.
As mass-produced versions of fermented tofu become more common, it is crucial to maintain traditional, artisanal techniques such as those found in Lugu (the use of ceramic jars, adobe storage rooms, naturally occurring molds, etc.), and to pass them on to the next generation.