Seitan is a food made from gluten, the main protein of wheat. It is made by washing wheat flour dough with water until all the starch dissolves, leaving insoluble gluten as an elastic mass which is then cooked before being eaten.
Wheat gluten is an alternative to soybean-based meat substitutes such as tofu. Some types of wheat gluten have a chewy or stringy texture that resembles meat more than other substitutes. Wheat gluten is often used instead of meat in Asian, vegetarian, Buddhist, and macrobiotic cuisines. Simulated duck is a common use for wheat gluten.
Wheat gluten was first developed in China, and historically has also been popular in the cuisines of Japan, Taiwan and other East and Southeast Asian countries. In Asia, it is commonly found on the menus of restaurants catering primarily to Buddhist customers who do not eat meat.
Some parts of the text are taken from English Wikipedia