Origins of mock chicken & duck
 

Wheat gluten, called miàn jin literally "noodle/dough tendon"; also spelled mien chin or mien ching) is believed to have originated in ancient China, as a meat substitute for adherents of Buddhism, particularly some Mahayana Buddhist monks, who are strict vegetarians. One story attributes the invention of imitation meat to chefs who made it for Chinese emperors who, traditionally, observed a week of vegetarianism each year. Miàn jin is often deep fried before being cooked in Chinese cuisine, which confers a crispy rind that enhances the texture of the gluten.

There are three primary Chinese forms of wheat gluten:

  1. Oily/oil fried gluten (yóu miàn jin): Raw gluten that has been torn into small bits, then deep fried into small puffy balls of around 3–5 cm in diameter and sold as "imitation abalone". They are golden brown in color, and braised or boiled in a savory soup or stew before eating. They are frequently paired with xiang gu (black mushrooms).
    • Larger fried balls of gluten, called miàn jin qiú  or miàn jin pao, which may be up to 5 inches in diameter, are sometimes seen in Asian supermarkets. These are often stuffed with meat or tofu mixtures and served as a dish called "gluten meatballs" (Miàn jin roù yuán) or "gluten stuffed with meat" (miàn jin sai roù).
  2. Steamed gluten (zheng miàn jin): Raw gluten that has been wrapped around itself to form a long sausage shape which is then steamed. This type of gluten has a dense texture and ranges from off-white to light greenish grey in color. It is torn open into strips before being used as an ingredient in recipes. When this sausage-shaped gluten is thickly sliced into medallions, the resulting form is called miàn lún (literally "gluten wheels"). Larger blocks of steamed gluten are sometimes colored pink and sold as vegetarian "mock ham."
  3. Baked spongy gluten (traditional: ??; simplified: ??; pinyin: kao fu): Similar in texture to a sponge, kao fu (sometimes labeled in English as "bran puff") is made by leavening raw gluten, then baking or steaming it. These are sold as small blocks in Chinese markets and are then diced up and cooked. This type of gluten absorbs its cooking liquid like a sponge and is enjoyed for its "juicy" character. Chinese kao fu is coarser in texture than its Japanese counterpart, yaki-fu, due to the relatively larger air bubbles it contains. Kao fu is available in fresh, frozen, and canned forms.

Freshly prepared miàn jin can be difficult to find in Chinese restaurants other than those specializing in Buddhist or vegetarian cuisine. Depending on its method of preparation and ingredients used, both fresh and preserved miàn jin can be used to simulate pork, poultry, beef, or even seafood.