Also known as soybean curd and bean curd, custardlike white tofu is made from curdled soy milk, an iron-rich liquid extracted from ground, cooked soybeans. The resulting curds are drained and pressed in a fashion similar to cheesemaking. The firmness of the resulting tofu cake depends on how much whey has been pressed out. Tofu is popular throughout the Orient, particularly in Japan. It has a bland, slightly nutty flavor that gives it a chameleonlike capability to take on the flavor of the food with which it's cooked. Tofu's texture is smooth and creamy yet it's firm enough to slice. It's available in health-food stores, Asian markets and many supermarkets. The cakes are sold in a variety of forms including packaged in water, vacuum-packed and in bulk (usually in large crocks or jars of water). Tofu, which is sometimes fortified with calcium, is very perishable and should be refrigerated for no more than a week. If it's packaged in water, drain it and cover with fresh water. All tofu should be stored covered with water, which should be changed daily. Tofu can be frozen up to 3 months. Freezing will change its texture, making it slightly chewier. The versatile tofu can be sliced, diced or mashed and used in a variety of dishes including soups, stir-fries, casseroles, salads, sandwiches, salad dressings and sauces. It's easy to digest, low in calories, calcium and sodium, high in protein and cholesterol-free — all of which makes it one of today's most healthful foods.