Tofu is created with soymilk, which is extracted from soybeans. The milk undergoes a coagulation process. After the milk is coagulated, slurry-like curds are pressed together to create a singular block; the result is tofu. To preserve freshness after opening the package, place the remaining tofu in a container with a lid, partially fill with cold distilled or spring water, then cover and refrigerate. We recommend using distilled or spring water. Municipal water systems usually add chlorine and other chemicals to water that can influence the taste of the tofu.