Okara (food)

Okara or Soy Pulp is a pulp consisting of insoluble parts of the soybean^[1] which remains after pureed soybeans are filtered in the production of soy milk and tofu.^[2] It is generally white or yellowish in color. It is part of the traditional cuisines of Japan, Korea, and China, and since the 20th century has also been used in the vegetarian cuisines of Western nations.

Okara that is firmly packed consists of 3.5 to 4.0% protein, 76 to 80% moisture and 20 to 24% of solids.^[1] When moisture free, okara contains 8 to 15% fats, 12 to 14.5% crude fiber and 24% protein, and contains 17% of the protein from the source soybeans.^[1] It also contains calcium, iron, and riboflavin.^{[citation needed]}

Typically, okara is a food by-product from tofu and soy milk production.^[2] In 1983 it was estimated that the annual yield for okara in Japan was approximately 70,000 metric tons.^[3] Due to its high moisture and nutrient content, okara is highly prone to putrefaction.^[3]

While relatively flavourless when eaten on its own, it can be used in stews such as the Korean biji-jjigae (비지찌개),^photo or in porridges. It's also used as an addition to baked goods such as breads, cookies and muffins, and can serve to create a crumbly texture in these foods.^[4] In Japan it is used in a side dish called unohana (卯の花),^photo which consists of okara cooked with soy sauce, mirin, sliced carrots, burdock root and shiitake mushrooms. Occasionally unohana is used as a substitute for the rice in sushi.^[5] Okara can also be fermented with the fungus Rhizopus^[4] (Rhizopus oligosporus) to make okara tempeh^[4] (called tempe gembus in Indonesian). Okara tempeh can also be made using a tempeh starter.^[6] Additionally, okara can be used in the preparation of other types of presscake tempehs that utilize ingredients such as brown rice, bulgur wheat, soybeans and other legume and grain combinations.^[7]

Okara is also eaten in the Shandong cuisine of eastern China by steaming a wet mixture of okara that has been formed into blocks of zha doufu (渣豆腐; literally "tofu from (soy) sediment/residue"), also known as xiao doufu or cai doufu,(小豆腐/菜豆腐; literally "little tofu" or "vegetable tofu").^[8] Often the dish is made directly from ground soybeans without first turning it into okara. The texture of this dish vaguely resembles polenta.

The product is sometimes used as an ingredient in vegetarian burger patties. Additional uses include processing into a granola product, as an ingredient in soysage and as an ingredient in patés.^[4] The majority of okara in poorer countries is used as food.^[1]

Okara is also used as livestock fodder^[9] for hogs and dairy cattle, and most of the product from soymilk dairies and tofu shops in the United States and Japan is used in this manner.^[1] It is often fed along with silage or hay, or blended in a mixed ration.^[9] As a significant byproduct of soy milk and tofu manufacturing, okara is commonly used as animal feed since its production usually exceeds demands for human consumption. For this reason, it is not uncommon for tofu and soymilk factories to be located close to animal farms in many Asian countries.

The product is also utilized as an ingredient in pet foods.^[4]

Okara is sometimes added to compost to add organic nutrients and nitrogen.^[4]

Okara is also the raw material used to make soy yarn. In Japan, okara is used to manufacture biodegradable cat litter.

• Food portal

• Shurtleff, William; Aoyagi, Akiko (1979). Tofu & Soymilk Production. Volume 2: The Book of Tofu. ISBN 1928914047
• Applewhite, Thomas H. (editor) (1989). Proceedings of the World Congress on Vegetable Protein Utilization in Human Food and Animal Foodstuffs. The American Oil Chemists Society. ISBN 093531525X

Wikimedia Commons has media related to Soy pulp.

• Ellen's Kitchen: okara tempeh
• Okara Mountain: recipe blog
• Okara Project: recipe blog