|Soybeans||1 1⁄2 Cup (24 tbs)|
|Water||1 (As Required)|
1. Wash and sort soybeans. Soak in 4 1/2 cups water for 8 hours in summer or 20 hours in winter. Reserve water. (Soaking water should always be 3 times volume of beans. The better the water, the better the final taste of the tofu.)
2. After soaking, divide beans and soaking water into several easy-to-handle portions according to the size of your blender. (By volume, the amount of beans to water should be the same. If the amount of soaking water is not sufficient, add water.) Puree each portion for 2 minutes in a blender.
3. Bring 4 cups water to a boil in a large pot and add pureed beans. Bring to a boil over medium heat, stirring continuously to prevent scorching. When foam rises to the top of pot, turn off heat. After foam recedes somewhat, cook for 5 minutes over very low heat, stirring constantly.
4. Mix calcium sulfate with 1 1/2 Tbsps water. Stir until powder is completely dissolved.
5. Prepare a cheesecloth-lined colander. Filter liquid through cheesecloth. Pull up ends of cloth, then twist while holding with large tongs (or clean pliers) and squeeze out as much liquid as possible. This liquid is the "soy milk." The material left in the cloth is okara, or "tofu pulp."
6. Heat (or cool) soy milk over low heat to 165°F (75°C). Keep a careful eye on soy milk and adjust heat to prevent boiling over. Stir once or twice. While soy milk is still circulating, add calcium sulfate mixture in one sweeping circular motion and stir only once or twice. Do not overstir. Let stand for 10 minutes.
7. Line a metal colander, wooden tofu box, or 1-quart (1-liter) plastic container that has drainage holes with cheesecloth. (The cheesecloth must be large enough so that it can be folded over to cover coagulating tofu mixture. If using perforated plastic container, prop up both ends to allow quick drainage.) Place in sink or in a pan to catch drainage.
8. Pour liquid into colander and fold ends of cheesecloth over top. Place a plate on top of cheesecloth (for tofu box use wooden top), and a 2-lb (1-kg) weight on top of the plate (a 2-cup measuring cup filled with water works well). Let stand for 15 to 20 minutes.
9. Lift tofu out of colander by taking hold of cheesecloth, and lower into a large bowl of cold water. (If using a tofu box, remove bottom and allow tofu to slide into a large bowl of cold water.) Gently unwrap while it is under water.
10. Soak tofu in cold water for 30 minutes (to remove excess coagulant). Use tofu as desired, or follow the three simple steps in Chilled Fresh Tofu and savor tofu at its freshest.