Made from fermented, protein-rich soy beans, this is an indispensable seasoning to Chinese cooking. There are two main kinds, the thick and the thin, or the dark and the light, both of which are used in Chinese homes and restaurants. Thick soy sauce is darker in color, thicker in consistency and less salty in taste, while thin soy sauce is lighter, thinner, and more salty. Often they are used together in conjunction with salt, but since thick soy sauce gives a reddish-brown hue to food, do not use it in marinating or seasoning ingredients when a light appearance is called for. Soy sauce is usually packaged in bottles but also comes in cans.