Can you tell me how tofu is made and if all tofu is fermented?

Originating in China well over a thousand years ago, tofu is made by curdling soymilk so that soymilk proteins become coagulated. The resulting soy curds can then be pressed into a sliceable cake. "Nigari" tofu typically refers to soymilk that has ...

from The World's Healthiest Foods http://ift.tt/2jKEEoV