Tofu is made from soymilk curdled with a coagulant, usually nigari (magnesium chloride) or gypsum (calcium sulfate). Similar to bland, firm, custard, tofu takes on the flavor of any seasonings. It is high in protein and (if made with calcium sulfate) calcium, and contains vitamins B complex, vitamin E and phytoestrogens (which may ease menopausal symptoms and may have a protective effect against prostate and reproductive cancers).