Coagulants in Fresh Tofu

The proteins in liquid soy “milk” must be bound together to form tofu, in the same way as cheese, through the introduction of a coagulant. Inland Chinese tofu makers traditionally used quarry-mined gypsum, while coastal manufacturers used sea-extracted nigari (called bittern in the West).

I find tofu coagulated with nigari to be slightly sweeter and finer in taste, whereas gypsum-coagulated tofu often has an almost “smoky” quality. It is a fine point, which furthermore may hold true only for domestic American-manufactured tofu, and may have as much to do with the water as with the coagulant used, but it is nonetheless something I look for when buying tofu.