''Okara'', soy pulp, or tofu dregs is a pulp consisting of insoluble parts of the

soybean The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean, which has numerous uses. Traditional unfermented food uses of soybeans include soy milk, from which tofu an ...

that remain after pureed soybeans are

filter Filter, filtering or filters may refer to: Science and technology Computing * Filter (higher-order function), in functional programming * Filter (software), a computer program to process a data stream * Filter (video), a software component tha ...

ed in the production of

soy milk Soy milk (simplified Chinese: 豆浆; traditional Chinese: 豆漿) also known as soya milk or soymilk, is a plant-based drink produced by soaking and grinding soybeans, boiling the mixture, and filtering out remaining particulates. It is a sta ...

and

tofu Tofu (), also known as bean curd in English, is a food prepared by coagulating soy milk and then pressing the resulting curds into solid white blocks of varying softness; it can be ''silken'', ''soft'', ''firm'', ''extra firm'' or ''super firm ...

. It is generally white or yellowish in color. It is part of the traditional cuisines of

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

Korea Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...

, and

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...

. Since the 20th century, it has been used in the

vegetarian cuisine Vegetarian cuisine is based on food that meets vegetarian standards by not including meat and animal tissue products (such as gelatin or animal-derived rennet). Lacto-ovo vegetarianism (the most common type of vegetarianism in the Western world) ...

s of Western nations. It is called ''dòuzhā'' or ''dòufuzhā'' in

Chinese Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of ...

, ''okara'' in

Japanese Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspor ...

, and ''biji'' or ''kongbiji'' in

Korean Korean may refer to: People and culture * Koreans, ethnic group originating in the Korean Peninsula * Korean cuisine * Korean culture * Korean language **Korean alphabet, known as Hangul or Chosŏn'gŭl **Korean dialects and the Jeju language ** ...

. Okara is the oldest of three basic types of soy fiber. The other two are soy bran (finely ground soybean hulls) and soy cotyledon/isolate fiber (the fiber that remains after making isolated soy protein, also called "soy protein isolate").

Production

Okara is a food

by-product A by-product or byproduct is a secondary product derived from a production process, manufacturing process or chemical reaction; it is not the primary product or service being produced. A by-product can be useful and marketable or it can be consid ...

from

and soy drink production.David B. Haytowitz and Ruth H. Matthews for the USDA Human Nutrition Information Service December 198
Agriculture Handbook No. 8-16. Composition of Foods: Legumes and Legume Products
In 1983 it was estimated that the annual yield for okara in Japan was approximately 70,000 metric tons.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. Due to its high moisture and nutrient content, okara is highly prone to

putrefaction Putrefaction is the fifth stage of death, following pallor mortis, algor mortis, rigor mortis, and livor mortis. This process references the breaking down of a body of an animal, such as a human, post-mortem. In broad terms, it can be viewed ...

, and this has limited its commercial use.Soy20/20. Spring 200
Okara: Overview of Current Utilization

Composition

Okara that is firmly packed consists of 3.5 to 4.0% protein, 76 to 80% moisture and 20 to 24% of solids. When moisture free, the gritty 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. It also contains potassium, calcium,

niacin Niacin, also known as nicotinic acid, is an organic compound and a form of vitamin B3, an essential human nutrient. It can be manufactured by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variet ...

.Shurtleff, William; Aoyagi, Akiko (1979).
Tofu & Soymilk Production''
Volume 2: The Book of Tofu. Most of the soybean

isoflavone Isoflavones are substituted derivatives of isoflavone, a type of naturally occurring isoflavonoids, many of which act as phytoestrogens in mammals. Isoflavones are produced almost exclusively by the members of the bean family, Fabaceae (Leguminosae ...

s are left in okara, as well as vitamin B and the fat-soluble nutritional factors, which include

soy lecithin Lecithin (, from the Greek ''lekithos'' "yolk") is a generic term to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues which are amphiphilic – they attract both water and fatty substances (and so a ...

linoleic acid Linoleic acid (LA) is an organic compound with the formula COOH(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups are cis-trans isomerism, ''cis''. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 ''cis''-9,12. A linoleate is a salt (chem ...

linolenic acid Linolenic acid is a type of naturally-occurring fatty acid. It can refer to either of two octadecatrienoic acids (i.e. with an 18-carbon chain and three double bonds, which are found in the '' cis'' configuration), or a mixture of the two. Lino ...

phytosterol Phytosterols are phytosteroids, similar to cholesterol, that serve as structural components of biological membranes of plants. They encompass plant sterols and stanols. More than 250 sterols and related compounds have been identified. Free phyto ...

tocopherol Tocopherols (; TCP) are a class of organic chemical compounds (more precisely, various methylated phenols), many of which have vitamin E activity. Because the vitamin activity was first identified in 1936 from a dietary fertility factor in rats, i ...

, and

vitamin D Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D3 (c ...

. Okara contains some antinutritional factors:

trypsin inhibitors A trypsin inhibitor (TI) is a protein and a type of serine protease inhibitor (serpin) that reduces the biological activity of trypsin by controlling the activation and catalytic reactions of proteins. Trypsin is an enzyme involved in the breakdown ...

(mostly destroyed by cooking),

saponin Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...

s, and

soybean agglutinin Soybean agglutinins (SBA) also known as soy bean lectins (SBL) are lectins found in soybeans. It is a family of similar legume lectins. As a lectin, it is an antinutrient that chelates minerals. In human foodstuffs, less than half of this lect ...

s, which cannot be easily digested.

Fermentation Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In food ...

(by proper species of bacteria) of okara is conducive to digestion and absorption of okara nutrients, and it further improves the nutritional value. It can eliminate the bean's odor, increase the amount of edible fiber, free amino acids, sugars, fatty acids, vitamin B12, vitamin B2, and

flavoprotein Flavoproteins are proteins that contain a nucleic acid derivative of riboflavin. Flavoproteins are involved in a wide array of biological processes, including removal of radicals contributing to oxidative stress, photosynthesis, and DNA repair ...

Uses

Most okara worldwide is used as feed for livestock — especially hogs and dairy cows. Most of the rest is used as a natural fertilizer or compost, which is fairly rich in nitrogen. A small amount is used in cookery.

Human consumption

In Japan it is used in a side dish called ''unohana'' which consists of okara cooked with

soy sauce Soy sauce (also called simply soy in American English and soya sauce in British English) is a liquid condiment of Chinese origin, traditionally made from a fermented paste of soybeans, roasted grain, brine, and '' Aspergillus oryzae'' or ''Asp ...

mirin is a type of rice wine and a common ingredient in Japanese cooking. It is similar to sake but with a lower alcohol content and higher sugar content. The sugar content is a complex carbohydrate that forms naturally during the fermentation pro ...

, sliced carrots,

burdock ''Arctium'' is a genus of biennial plants commonly known as burdock, family Asteraceae. Native to Europe and Asia, several species have been widely introduced worldwide. Burdock's clinging properties, in addition to providing an excellent mecha ...

root and

shiitake The shiitake (alternate form shitake) (; ''Lentinula edodes'') is an edible mushroom native to East Asia, which is now cultivated and consumed around the globe. It is considered a Medicinal fungi, medicinal mushroom in some forms of tradition ...

mushrooms. Okara can be used to make

tempeh Tempeh or tempe (; jv, ꦠꦺꦩ꧀ꦥꦺ, témpé, ) is a traditional Indonesian food made from fermented soybeans. It is made by a natural culturing and controlled fermentation process that binds soybeans into a cake form. A fungus, ''Rhizopus ...

, by fermenting with the fungus ''

Rhizopus oligosporus ''Rhizopus oligosporus'' is a fungus of the family Mucoraceae and is a widely used starter culture for the production of tempeh at home and industrially. As the mold grows it produces fluffy, white mycelia, binding the beans together to create ...

,'' using a tempeh starter. It can make

press cake A press cake or oil cake is the solids remaining after pressing something to extract the liquids. Their most common use is in animal feed. Some foods whose processing creates press cakes are olives for olive oil (''pomace''), peanuts for ...

tempeh using ingredients such as brown rice, bulgur wheat, soybeans and other legume and grain combinations. Okara is also eaten as red

oncom Oncom ( Aksara Sunda: ; IPA: ) is one of the traditional staple foods of West Java (Sundanese) cuisine of Indonesia. There are two kinds of oncom: red oncom and black oncom. Oncom is closely related to tempeh; both are foods fermented using mold. ...

by the

Sundanese people The Sunda or Sundanese ( id, Orang Sunda; su, ᮅᮛᮀ ᮞᮥᮔ᮪ᮓ, Urang Sunda) are an indigenous ethnic group native to the western region of Java island in Indonesia, primarily West Java. They number approximately 42 million and form ...

on Java in

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

after fermentation by

Neurospora ''Neurospora'' is a genus of Ascomycete fungi. The genus name, meaning "nerve spore" refers to the characteristic striations on the spores that resemble axons. The best known species in this genus is ''Neurospora crassa'', a common model organi ...

. Okara is eaten in the Shandong cuisine of eastern China by steaming a wet mixture of okara that has been formed into blocks of ''zha doufu'' (also known as ''xiao doufu'' or ''cai doufu''). 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

pâté ''Pâté'' ( , , ) is a paste, pie or loaf filled with a forcemeat. Common forcemeats include ground meat from pork, poultry, fish or beef; fat, vegetables, herbs, spices and either wine or brandy (often cognac or armagnac). It is often served ...

s. In Japan, there have been experiments with incorporating okara into

ice cream Ice cream is a sweetened frozen food typically eaten as a snack or dessert. It may be made from milk or cream and is flavoured with a sweetener, either sugar or an alternative, and a spice, such as cocoa or vanilla, or with fruit such as str ...

. U-no-hana, at The Meshiya (2014-10-18).JPG, ''Unohana'', a typical Japanese dish made from okara Vegan okara burgers.jpg,

Vegan Veganism is the practice of abstaining from the use of animal product—particularly in diet—and an associated philosophy that rejects the commodity status of animals. An individual who follows the diet or philosophy is known as a vegan. Di ...

okara burgers Okara in the sieve.jpg, okara in a

sieve A sieve, fine mesh strainer, or sift, is a device for separating wanted elements from unwanted material or for controlling the particle size distribution of a sample, using a screen such as a woven mesh or net or perforated sheet material. T ...

Livestock consumption

Most okara is used as

animal feed Animal feed is food given to domestic animals, especially livestock, in the course of animal husbandry. There are two basic types: fodder and forage. Used alone, the word ''feed'' more often refers to fodder. Animal feed is an important input to ...

, especially for farms in vicinity of soy milk or tofu factories.

In pet food

The product is used as an ingredient in pet foods.

As fertilizer or compost

Okara is sometimes spread on fields as a natural nitrogen fertilizer. It adds

tilth Tilth is a physical condition of soil, especially in relation to its suitability for planting or growing a crop. Factors that determine tilth include the formation and stability of aggregated soil particles, moisture content, degree of aeration, s ...

to the soil. Likewise, it can be added to

compost Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical and biological properties. It is commonly prepared by decomposing plant, food waste, recycling organic materials and manure. The resulting m ...

to add organic nutrients and nitrogen.

Waste/environment

When not considered foodstuff, it may be deemed 'soybean curd residue' (SCR). Some 800,000 tons of soybean curd residue is disposed annually as tofu production byproducts in Japan. As mass waste, it is a potential environmental problem because it is highly susceptible to

. The protein in SCR is of better quality than from other soy products; for example, the

protein efficiency ratio Protein efficiency ratio (PER) is based on the weight gain of a test subject divided by its intake of a particular food protein during the test period. From 1919 until very recently, the PER had been a widely used method for evaluating the quality ...

of SCR is 2.71 compared with 2.11 for soymilk. The ratio of essential amino acids to total amino acids is similar to tofu and soymilk. Nevertheless, it remains a challenge to current processes to commercially extract the proteins and nutrients from SCR waste.

References

External links

Ellen's Kitchen: okara tempeh

Okara Mountain: recipe blog

Okara Project: recipe blog
{{DEFAULTSORT:Okara (Food) Soy-based foods Shandong cuisine Japanese cuisine Japanese cuisine terms Vegan cuisine Vegetarian cuisine Tofu Vegetarian dishes of China Vegetarian dishes of Japan