How tofu is made
Tofu is made like cheese, with soy milk curdled by a mineral and pressed into blocks.
- stations
- 7
- things upstream
- 3
- raw sources
- 3
- step from the ground
- 1
The short version
Soybeans are soaked, ground with water and cooked into soy milk. Filtering removes the pulp, and a coagulant such as calcium sulfate, nigari or glucono delta-lactone is stirred in so the proteins gel into curd. The curds are pressed in molds to drain the whey. The firmness depends on how much liquid is squeezed out.
-
Soak the beans
Dried soybeans swell in water for hours until they are plump. Soft beans grind to a smoother slurry.
-
Grind with water
The soaked beans are ground with fresh water into a thick slurry. Grinding breaks the cells open and releases protein and oil.
-
Boil the slurry
Steam cooks the slurry. Heat deactivates compounds in raw soy that interfere with digestion, and it prepares the proteins to gel.
-
Strain out the pulp
A filter press or centrifuge separates the liquid soy milk from the fibrous pulp, called okara. The pulp is used in feed or other foods.
-
Curdle with a coagulant
Calcium sulfate, magnesium chloride (nigari), glucono delta-lactone or an edible acid is stirred into hot soy milk. Calcium and magnesium ions link the soy proteins into a gel. The choice of coagulant sets the texture, with gypsum giving tender but slightly brittle tofu and GDL giving silken tofu.
Goes in -
Press into blocks
The curd is broken up, ladled into cloth-lined molds and pressed so whey runs out. Pressing longer makes firm and extra-firm tofu, while silken tofu is left to set unpressed in its package.
-
Cut, chill and pack
Blocks are cut to size, cooled in clean water, packed in tubs with water and often pasteurized.
Worth repeating
- Chinese legend credits tofu to Prince Liu An, who lived from 179 to 122 BC.
- Benjamin Franklin mentioned tofu in a 1770 letter, calling it cheese from China.
- Before refrigeration, tofu in China was usually sold only in winter.
Back to the ground
Follow every input upstream and tofu starts as these 3 raw sources.
Keep walking
Sources
Cite this page: "How tofu is made." Assembly Line, 2026-11-03. https://assemblyline.org/make/tofu