Soybean

Thesoybean,soy bean, orsoya bean(Glycine max)is a species oflegumenative toEast Asia, widely grown for its ediblebean, which has numerous uses.
Traditional unfermented food uses of soybeans includesoy milk, from whichtofuandtofu skinare made. Fermented soy foods includesoy sauce,fermented bean paste,nattō, andtempeh. Fat-free (defatted) soybean meal is a significant and cheap source of protein for animal feeds and manypackaged meals.For example, soybean products, such astextured vegetable protein(TVP), are ingredients in many meat anddairysubstitutes.
Soybeans contain significant amounts ofphytic acid,dietary mineralsandB vitamins.Soy vegetable oil, used in food and industrial applications, is another product of processing the soybean crop. Soybean is a common protein source in feed for farm animals that in turn yield animal protein for human consumption.
The word "soy" derives from the Japanesesoi, a regional variant ofshōyu, meaning "soy sauce".
The name of the genus,Glycine, comes fromLinnaeus. When naming the genus, Linnaeus observed that one of the species within the genus had a sweet root. Based on the sweetness, the Greek word for sweet,glykós, was Latinized.The genus name is not related to the amino acidglycine.
Like most plants, soybeans grow in distinctmorphologicalstages as they develop from seeds into fully mature plants.
The first stage of growth isgermination, a method which first becomes apparent as a seed'sradicleemerges.This is the first stage of root growth and occurs within the first 48 hours under ideal growing conditions. The firstphotosyntheticstructures, thecotyledons, develop from thehypocotyl, the first plant structure to emerge from the soil. These cotyledons both act as leaves and as a source of nutrients for the immature plant, providing the seedling nutrition for its first 7 to 10 days.
The first true leaves develop as a pair ofsingle blades.Subsequent to this first pair, maturenodesform compound leaves with three blades. Maturetrifoliolateleaves, having three to fourleafletsper leaf, are often between6 and 15 cm (2+1⁄2and 6 in) long and 2 and 7 cm (1 and 3 in) broad. Under ideal conditions, stem growth continues, producing new nodes every four days. Before flowering, roots can grow2 cm (3⁄4in) per day. Ifrhizobiaare present,root nodulationbegins by the time the third node appears. Nodulation typically continues for 8 weeks before thesymbiotic infectionprocess stabilizes.The final characteristics of a soybean plant are variable, with factors such as genetics,soil quality, and climate affecting its form; however, fully mature soybean plants are generally between 50 and 125 cm (20 and 50 in) in heightand have rooting depths between 75 and 150 cm (30 and 60 in).
Flowering istriggered by day length, often beginning once days become shorter than 12.8 hours.This trait is highly variable however, with differentvarietiesreacting differently to changing day length.Soybeans form inconspicuous, self-fertile flowers which are borne in theaxilof the leaf and are white, pink or purple. Though they do not require pollination, they are attractive to bees, because they produce nectar that is high in sugar content.Depending on the soybean variety, node growth may cease once flowering begins. Strains that continue nodal development after flowering are termed "indeterminates" and are best suited to climates with longer growing seasons.Often soybeans drop their leaves before the seeds are fully mature.
The fruit is a hairy pod that grows in clusters of three to five, each pod is 3–8 cm (1–3 in) long and usually contains two to four (rarely more)seeds5–11 mm in diameter. Soybean seeds come in a wide variety of sizes andhullcolors such as black, brown, yellow, and green.Variegated and bicolored seed coats are also common.
The hull of the mature bean is hard, water-resistant, and protects thecotyledonandhypocotyl(or "germ") from damage. If the seed coat is cracked, the seed will notgerminate. The scar, visible on the seed coat, is called thehilum(colors include black, brown, buff, gray and yellow) and at one end of the hilum is themicropyle, or small opening in the seed coat which can allow the absorption of water for sprouting.
Some seeds such as soybeans containing very high levels ofproteincan undergodesiccation, yet survive and revive after water absorption.A. Carl Leopoldbegan studying this capability at theBoyce Thompson Institute for Plant ResearchatCornell Universityin the mid-1980s. He found soybeans and corn to have a range of solublecarbohydratesprotecting the seed's cell viability.Patents were awarded to him in the early 1990s on techniques for protecting biological membranes and proteins in the dry state.
Dry soybeans contain 36%proteinand 20%fatin form ofsoybean oilby weight. The remainder consists of 30%carbohydrates, 9% water and 5%ash.Soybeans comprise approximately 8% seed coat or hull, 90%cotyledonsand 2%hypocotylaxis or germ.
The genusGlycinemay be divided into two subgenera,GlycineandSoja. The subgenusSojaincludes the cultivated soybean,G. max, and the wild soybean, treated either as a separate speciesG. soja,or as the subspeciesG. maxsubsp.soja.The cultivated and wild soybeans areannuals. The wild soybean is native toChina,Japan,KoreaandRussia.The subgenusGlycineconsists of at least 25 wildperennialspecies: for example,G. canescensandG. tomentella, both found inAustraliaandPapua New Guinea.Perennial soybean (Neonotonia wightii) belongs to a different genus. It originated in Africa and is now a widespread pasture crop in the tropics.
Like some other crops of long domestication, the relationship of the modern soybean to wild-growing species can no longer be traced with any degree of certainty.It is acultigenwith a very large number ofcultivars.
Like many legumes, soybeans canfix atmospheric nitrogen, due to the presence ofsymbioticbacteria from theRhizobiagroup.
Cultivation is successful in climates with hot summers, with optimum growing conditions in mean temperatures of 20 to 30 °C (70 to 85 °F); temperatures of below 20 °C (70 °F) and over 40 °C (105 °F) stunt growth significantly. They can grow in a wide range of soils, with optimum growth in moistalluvial soilswith good organic content. Soybeans, like most legumes, performnitrogen fixationby establishing asymbioticrelationship with the bacteriumBradyrhizobium japonicum(syn.Rhizobium japonicum; Jordan 1982). This ability to fix nitrogen allows farmers to reduce nitrogenfertilizeruse and increase yields when growing other crops inrotationwith soy.There may be some trade-offs, however, in the long-term abundance oforganic material in soilswhere soy and other crops (for example,corn) are grown in rotation.For best results, though, an inoculum of the correct strain of bacteria should be mixed with the soybean (or any legume) seed before planting. Modern cropcultivarsgenerally reach a height of around 1 m (3 ft), and take 80–120 days from sowing to harvesting.
Soil scientistsEdson Lobato(Brazil),Andrew McClung(U.S.), andAlysson Paolinelli(Brazil) were awarded the 2006World Food Prizefor transforming the ecologically biodiverse savannah of theCerradoregion of Brazil into highly productive cropland that could grow profitable soybeans.
Humansewage sludgecan be used as fertilizer to grow soybeans. Soybeans grown in sewage sludge likely contain elevated concentrations of metals.
Soybean plants are vulnerable to a wide range ofbacterial diseases,fungal diseases,viral diseases, and parasites.
The primary bacterial diseases includebacterial blight,bacterial pustuleanddowny mildewaffecting the soybean plant.
TheJapanese beetle(Popillia japonica) poses a significant threat to agricultural crops, including soybeans, due to its voracious feeding habits. Found commonly in both urban and suburban areas, these beetles are frequently observed in agricultural landscapes where they can cause considerable damage to crops like corn, soybeans, and various fruits.
Soybean cyst nematode(SCN) is the worst pest of soybean in the US. Losses of 30%or 40%are common even without symptoms.
Thecorn earworm moth and bollworm(Helicoverpa zea) is a common and destructive pest of soybean growth in Virginia.
Soybeans are consumed bywhitetail deerwhich may damage soybean plants through feeding, trampling and bedding, reducingcrop yieldsby as much as 15%.Groundhogsare also a common pest in soybean fields, living in burrows underground and feeding nearby. One den of groundhogs can consume a tenth to a quarter of an acre of soybeans.Chemical repellentsorfirearmsare effective for controlling pests in soybean fields.
Soybeans suffer from the fungusPythium spinosuminArkansasandIndiana(United States), and China.
In Japan and the United States, theSoybean dwarf virus(SbDV) causes a disease in soybeans and is transmitted by aphids.
Resistant varietiesare available. In Indian cultivars, Natarajet al.2020 find that anthracnose caused byColletotrichum truncatumis resisted by a combination of 2 major genes.
The vast majority of cultivars in the US havesoybean cyst nematode resistance(SCN resistance), but rely ononly one breeding line (PI 88788)as their sole source of resistance.(The resistance genes provided by PI 88788,Peking, andPI 90763werecharacterizedin 1997.)As a result, for example, in 2012 only 18 cultivars out of 807 recommended by theIowa State University Extensionhad any ancestry outside of PI 88788. By 2020 the situation was still about the same: Of 849 there were 810 with some ancestry from PI 88788,35 from Peking, and only 2 from PI 89772. (On the question of exclusively PI 88788 ancestry, that number was not available for 2020.)That was speculated to be in 2012—and was clearly by 2020—producing SCN populations that are virulent on PI 88788.
In 2020, world production of soybeans was over 353 million tonnes, led by Brazil and the United States combined with 66% of the total (table). Production has dramatically increased across the globe since the 1960s, but particularly in South America after a cultivar that grew well in low latitudes was developed in the 1980s.The rapid growth of the industry has been primarily fueled by large increases inworldwide demand for meatproducts, particularly in developing countries like China, which alone accounts for more than 60% of imports.
In spite of the Amazon "Soy Moratorium", soy production continues to play a significant role indeforestationwhen its indirect impacts are taken into account, as land used to grow soy continues to increase. This land either comes frompastureland (which increasingly supplants forested areas), or areas outside the Amazon not covered by the moratorium, such as theCerradoregion. Roughly one-fifth of deforestation can be attributed to expanding land use to produce oilseeds, primarily for soy andpalm oil, whereas the expansion ofbeefproduction accounts for 41%. The main driver of deforestation is the global demand for meat, which in turn requires huge tracts of land to grow feed crops for livestock.Around 80% of the global soybean crop is used to feed livestock.
Soybeans were a crucial crop in East Asia long before written records began.The origin of soy bean cultivation remains scientifically debated. The closest living relative of the soybean isGlycine soja(previously calledG. ussuriensis), a legume native to central China.There is evidence for soybean domestication between 7000 and 6600 BC in China, between 5000 and 3000 BC in Japan and 1000 BC in Korea.
The first unambiguously domesticated,cultigen-sized soybean was discovered in Korea at theMumun-period Daundong site.Prior tofermentedproducts such as fermented black soybeans (douchi),jiang(Chinese miso),soy sauce,tempeh,nattō, andmiso, soy was considered sacred for its beneficial effects incrop rotation, and it was eaten by itself, and asbean curdandsoy milk.
Soybeans were introduced toJavainMalay Archipelagocirca 13th century or probably earlier. By the 17th century through their trade with Far East, soybeans and its products were traded by European traders (Portuguese, Spanish, and Dutch) in Asia, and reached Indian Subcontinent by this period.By the 18th century, soybeans were introduced to the Americas and Europe from China. Soy was introduced to Africa from China in the late 19th century, and is now widespread across the continent.
The cultivation of soybeans began in the eastern half of northern China by 2000 BC, but is almost certainly much older.The earliest documented evidence for the use ofGlycineof any kind comes from charred plant remains of wild soybean recovered from Jiahu inHenan provinceChina, aNeolithicsite occupied between 9000 and 7800 calendar years ago (cal bp).An abundance of archeological charred soybean specimens have been found centered around this region.
According to the ancient Chinese myth, in 2853 BC, the legendaryEmperor Shennongof China proclaimed that five plants were sacred: soybeans, rice, wheat, barley, andmillet.Early Chinese records mention that soybeans were a gift from the region ofYangtze River deltaand Southeast China.TheGreat Soviet Encyclopediaclaims soybean cultivation originated in China about 5000 years ago.Some scholars suggest that soybean originated in China and was domesticated about 3500 BC.Recent research, however, indicates that seeding of wild forms started early (before 5000 BC) in multiple locations throughout East Asia.
Soybeans became an important crop by the Zhou dynasty (c. 1046–256 BC) in China. However, the details of where, when, and under what circumstances soybean developed a close relationship with people are poorly understood. Soybean was unknown in South China before the Han period.From about the first century AD to theAge of Discovery(15–16th centuries), soybeans were introduced into across South and Southeast Asia. This spread was due to the establishment of sea and land trade routes. The earliest Japanese textual reference to the soybean is in the classicKojiki(Records of Ancient Matters), which was completed in AD 712.
The oldest preserved soybeans resembling modern varieties in size and shape were found inarchaeological sitesinKoreadated about 1000 BC.Radiocarbon datingof soybean samples recovered throughflotationduring excavations at the EarlyMumunperiod Okbang site in Korea indicated soybean was cultivated as a food crop in around 1000–900 BC.Soybeans from the Jōmon period in Japan from 3000 BCare also significantly larger than wild varieties.
Soybeans were mentioned askadêlê(modernIndonesianterm:kedelai)in anold Javanesemanuscript, SeratSri Tanjung, which dates to 12th- to 13th-centuryJava.By the 13th century, the soybean had arrived and cultivated in Indonesia; it probably arrived much earlier however, carried by traders or merchants from Southern China.
The earliest known reference to it as "tempeh" appeared in 1815 in theSerat Centhinimanuscript.The development of tempeh fermented soybean cake probably took place earlier, circa 17th century in Java.
By the 1600s, soy sauce spread from southern Japan across the region through theDutch East India Company(VOC).
While the origins and history of Soybean cultivation in theEastern Himalayasis debated, it was potentially introduced from southernChina, more specificallyYunnanprovince.Alternatively, it could have reached here through traders fromIndonesiaviaMyanmar.Northeast Indiais viewed as a passive micro-centre within the soybean secondary gene centre. Central India is considered a tertiary gene centre particularly the area encompassing Madhya Pradesh which is also the country largest soybean producer.
In 1603, "Vocabvlario da Lingoa de Iapam", a famous Japanese-Portuguese dictionary, was compiled and published by Jesuit priests in Nagasaki. It contains short but clear definitions for about 20 words related to soyfoods—the first in any European language.
The Luso-Hispanic traders were familiar with soybeans and soybean product through their trade with Far East since at least the 17th century. However, it was not until the late 19th century that the first attempt to cultivate soybeans in the Iberian peninsula was undertaken. In 1880, the soybean was first cultivated in Portugal in theBotanical Gardens at Coimbra(Crespi 1935).
In about 1910 in Spain the first attempts at Soybean cultivation were made by the Count of San Bernardo, who cultivated soybeans on his estates at Almillo (in southwest Spain) about 48 miles east-northeast of Seville.
Soybeans were first introduced to North America from China in 1765, bySamuel Bowen, a formerEast India Companysailor who had visited China in conjunction withJames Flint, the first Englishman legally permitted by the Chinese authorities to learn Chinese.The first "New World" soybean crop was grown onSkidaway Island, Georgia, in 1765 by Henry Yonge from seeds given him by Samuel Bowen.Bowen grew soy nearSavannah, Georgia, possibly using funds from Flint, and made soy sauce for sale to England.Although soybean was introduced into North America in 1765, for the next 155 years, the crop was grown primarily forforage.
In 1831, the first soy product "a few dozen India Soy" [sauce] arrived in Canada. Soybeans were probably first cultivated in Canada by 1855, and definitely in 1895 atOntario Agricultural College.
It was not untilLafayette MendelandThomas Burr Osborneshowed that the nutritional value of soybean seeds could be increased by cooking, moisture or heat, that soy went from a farm animal feed to a human food.
William Morse is considered the "father" of modern soybean agriculture in America. In 1910, he andCharles Piperbegan to popularize what was regarded as a relatively unknown Oriental peasant crop in America into a "golden bean", with the soybean becoming one of America's largest and most nutritious farm crops.
Prior to the 1920s in the US, the soybean was mainly aforagecrop, a source of oil, meal (for feed) and industrial products, with very little used as food. However, it took on an important role after World War I. During theGreat Depression, the drought-stricken (Dust Bowl) regions of the United States were able to use soy to regenerate their soil because of its nitrogen-fixing properties. Farms were increasing production to meet with government demands, andHenry Fordbecame a promoter of soybeans.In 1931, Ford hired chemistsRobert Boyerand Frank Calvert to produceartificial silk. They succeeded in making a textile fiber of spun soy protein fibers, hardened or tanned in aformaldehydebath, which was given the nameAzlon. It never reached the commercial market. Soybean oil was used byFordinpaintfor the automobiles,as well as a fluid for shock absorbers.
During World War II, soybeans became important in both North America and Europe chiefly as substitutes for other protein foods and as a source of edible oil. During the war, the soybean was discovered asfertilizerdue tonitrogen fixationby theUnited States Department of Agriculture.
Prior to the 1970s, Asian-Americans and Seventh-Day Adventists were essentially the only users of soy foods in the United States."The soy foods movement began in small pockets of the counterculture, notably the Tennessee commune named simplyThe Farm, but by the mid-1970s a vegetarian revival helped it gain momentum and even popular awareness through books such asThe Book of Tofu."
Although practically unseen in 1900, by 2000 soybean plantings covered more than 70 million acres,second only to corn, and it became America's largest cash crop.In 2021, 87,195,000 acres were planted, with the largest acreage in the states of Illinois, Iowa, and Minnesota.
The soybean arrived in the Caribbean in the form of soy sauce made by Samuel Bowen in Savannah, Georgia, in 1767. It remains only a minor crop there, but its uses for human food are growing steadily.
The soybean was first cultivated in Italy by 1760 in the Botanical Garden of Turin. During the 1780s, it was grown in at least three other botanical gardens in Italy.The first soybean product, soy oil, arrived inAnatoliaduring 1909 underOttoman Empire.The first clear cultivation occurred in 1931.This was also the first time that soybeans were cultivated in Middle East.By 1939, soybeans were cultivated in Greece.
Wild soybeans were discovered in northeastern Australia in 1770 by explorers Banks and Solander. In 1804, the first soyfood product ("Fine India Soy" [sauce]) was sold in Sydney. In 1879, the first domesticated soybeans arrived in Australia, a gift of the Minister of the Interior Department, Japan.
The soybean was first cultivated in France by 1779 (and perhaps as early as 1740). The two key early people and organizations introducing the soybean to France were the Society of Acclimatization (starting in 1855) andLi Yu-ying(from 1910). Li started a large tofu factory, where the first commercial soyfoods in France were made.
The soybean first arrived in Africa via Egypt in 1857.Soya Meme (Baked Soya) is produced in the village called Bame Awudome nearHo, the capital of theVolta RegionofGhana, by theEwe peopleof Southeastern Ghana and southern Togo.
In 1873, ProfessorFriedrich J. Haberlandtfirst became interested in soybeans when he obtained the seeds of 19 soybean varieties at theVienna World Exposition(Wiener Weltausstellung). He cultivated these seeds in Vienna, and soon began to distribute them throughout Central and Western Europe. In 1875, he first grew the soybeans in Vienna, then in early 1876 he sent samples of seeds to seven cooperators in central Europe, who planted and tested the seeds in the spring of 1876, with good or fairly good results in each case.Most of the farmers who received seeds from him cultivated them, then reported their results. Starting in February 1876, he published these results first in various journal articles, and finally in hismagnum opus, Die Sojabohne (The Soybean) in 1878.In northern Europe,lupin(lupine) is known as the "soybean of the north".
The soybean is first in cultivated Transcaucasia in Central Asia in 1876, by the Dungans. This region has never been important for soybean production.
The first reliable reference to the soybean in this region dates from Mexico in 1877.
The soybean first arrived in South America in Argentina in 1882.
Andrew McClung showed in the early 1950s that with soil amendments theCerradoregion of Brazil would grow soybeans.In June 1973, when soybean futures markets mistakenly portended a major shortage, theNixon administrationimposed an embargo on soybean exports. It lasted only a week, but Japanese buyers felt that they could not rely on U.S. supplies, and the rival Brazilian soybean industry came into existence.This led Brazil to become the world's largest producer of soybeans in 2020, with 131 million tons.
Industrial soy production in South America is characterized by wealthy management who live far away from the production site which they manage remotely. In Brazil, these managers depend heavily on advanced technology and machinery, and agronomic practices such as zero tillage, high pesticide use, and intense fertilization. One contributing factor is the increased attention on the BrazilianCerradoinBahia, Brazil by US farmers in the early 2000s. This was due to rising values of scarce farmland and high production costs in the US Midwest. There were many promotions of the Brazilian Cerrado by US farm producer magazines and market consultants who portrayed it as having cheap land with ideal production conditions, with infrastructure being the only thing it was lacking. These same magazines also presented Brazilian soy as inevitably out-competing American soy. Another draw to investing was the insider information about the climate and market in Brazil. A few dozen American farmers purchased varying amounts of land by a variety of means including finding investors and selling off land holdings. Many followed theethanolcompany model and formed anLLCwith investments from neighboring farmers, friends, and family while some turned to investment companies. Some soy farmers eitherliquidatedtheir Brazilian assets or switched to remote management from the US to return to farming there and implement new farming and business practices to make their US farms more productive. Others planned to sell their now expensive Bahia land to buy land cheaper land in the frontier regions ofPiauíorTocantinsto create more soybean farms.
Chineselandraceswere found to have a slightly higher genetic diversity than inbred lines by Liet al., 2010.Specific locus amplified fragment sequencing (SLAF-seq) has been used by Hanet al., 2015 to study the genetic history of thedomestication process, performgenome-wide association studies(GWAS) ofagronomically relevant traits, and producehigh-density linkage maps.AnSNP arraywas developed by Songet al., 2013 and has been used for research andbreeding;the same team applied their array in Songet al., 2015 against the USDA Soybean Germplasm Collection and obtained mapping data that are expected to yieldassociation mappingdata for such traits.
Rpp1-R1is aresistance geneagainstsoybean rust.Rpp1-R1 is anR gene(NB-LRR) providing resistance against the rust pathogenPhakopsora pachyrhizi.Its synthesis product includes aULP1 protease.
Qijianet al., 2017 provides theSoySNP50Kgene array.
Soybeans are one of the "biotechfood" crops that have beengenetically modified, and genetically modified soybeans are being used in an increasing number of products. In 1995,Monsantocompany introducedglyphosate-tolerantsoybeans that have been genetically modified to be resistant to Monsanto'sglyphosateherbicides through substitution of theAgrobacteriumsp.(strain CP4)geneEPSP (5-enolpyruvyl shikimic acid-3-phosphate) synthase. The substituted version is not sensitive toglyphosate.
In 1997, about 8% of all soybeans cultivated for the commercial market in the United States were genetically modified. In 2010, the figure was 93%.As with other glyphosate-tolerant crops, concern is expressed over damage tobiodiversity.A 2003 studyconcluded the "Roundup Ready" (RR) gene had been bred into so many different soybean cultivars, there had been little decline in genetic diversity, but "diversity was limited among elite lines from some companies".
The widespread use of such types of GM soybeans in the Americas has caused problems with exports to some regions. GM crops require extensive certification before they can be legally imported into theEuropean Union, where there is considerable supplier and consumer reluctance to use GM products for consumer or animal use. Difficulties withcoexistenceand subsequent traces of cross-contamination of non-GM stocks have caused shipments to be rejected and have put a premium on non-GM soy.
A 2006United States Department of Agriculturereport found the adoption of genetically engineered (GE) soy, corn and cotton reduced the amount of pesticides used overall, but did result in a slightly greater amount ofherbicidesused for soy specifically. The use of GE soy was also associated with greaterconservation tillage, indirectly leading to better soil conservation, as well as increased income from off-farming sources due to the greater ease with which the crops can be managed. Though the overall estimated benefits of the adoption of GE soybeans in the United States was $310 million, the majority of this benefit was experienced by the companies selling the seeds (40%), followed by biotechnology firms (28%) and farmers (20%).The patent on glyphosate-tolerant soybeans expired in 2014,so benefits can be expected to shift.
Allergy to soy is common, and the food is listed with other foods that commonly cause allergy, such as milk, eggs, peanuts, tree nuts, shellfish. The problem has been reported among younger children, and the diagnosis of soy allergy is often based on symptoms reported by parents and results of skin tests or blood tests for allergy. Only a few reported studies have attempted to confirm allergy to soy by direct challenge with the food under controlled conditions.It is very difficult to give a reliable estimate of the true prevalence of soy allergy in the general population. To the extent that it does exist, soy allergy may cause cases ofurticariaandangioedema, usually within minutes to hours of ingestion. In rare cases, trueanaphylaxismay also occur. The reason for the discrepancy is likely that soy proteins, the causative factor inallergy, are far less potent at triggering allergy symptoms than the proteins of peanut and shellfish.An allergy test that is positive demonstrates that the immune system has formed IgE antibodies to soy proteins. However, this is only a factor when soy proteins reach the blood without being digested, in sufficient quantities to reach a threshold to provoke actual symptoms.
Soy can also trigger symptoms viafood intolerance, a situation where no allergic mechanism can be proven. One scenario is seen in very young infants who have vomiting anddiarrhoeawhen fed soy-based formula, which resolves when the formula is withdrawn. Older infants can suffer a more severe disorder with vomiting, diarrhoea that may be bloody,anemia, weight loss and failure to thrive. The most common cause of this unusual disorder is a sensitivity to cow's milk, but soy formulas can also be the trigger. The precise mechanism is unclear and it could be immunologic, although not through the IgE-type antibodies that have the leading role in urticaria and anaphylaxis. However, it is also self-limiting and will often disappear in thetoddleryears.
In theEuropean Union, identifying the presence of soy either as an ingredient or unintended contaminant in packaged food is compulsory. The regulation (EC) 1169/2011 on food-labeling lists 14 allergens, including soy, in packaged food must be clearly indicated on the label as part of the list of ingredients, using a distinctive typography (such as bold type or capital letters).
One review noted that soy-based foods may inhibit absorption of thyroid hormone medications required for treatment ofhypothyroidism.A 2015 scientific review by theEuropean Food Safety Authorityconcluded that intake of isoflavones from supplements did not affect thyroid hormone levels inpostmenopausalwomen.
Among thelegumes, the soybean is valued for its high (38–45%)proteincontent as well as its high (approximately 20%) oil content. Soybeans are the most valuable agricultural export of the United States.Approximately 85% of the world's soybean crop is processed into soybean meal and soybean oil, the remainder processed in other ways or eaten whole.
Soybeans can be broadly classified as "vegetable" (garden) or field (oil) types. Vegetable types cook more easily, have a mild, nutty flavor, and better texture, are larger in size, higher in protein, and are lower in oil than field types.Tofu,soy milk, andsoy sauceare among the top edible commodities made using soybeans. Producers prefer the higher protein cultivars bred from vegetable soybeans originally brought to the United States in the late 1930s. The "garden" cultivars are generally not suitable for mechanical combine harvesting because there is a tendency for the pods to shatter upon reaching maturity.
A 100-gram reference quantity of raw soybeans supplies 1,866 kilojoules (446 kilocalories) offood energyand are 9% water, 30%carbohydrates, 20% totalfatand 36%protein.Peanutsare the onlylegumeswith a higher fat content (48%) and calorie count (2,385 kJ). They contain less carbohydrates (21%), protein (25%) and dietary fiber (9%).
Soybeans are a rich source ofessential nutrients, providing in a 100-gram serving (raw, for reference) high contents of theDaily Value(DV) especially for protein (36% DV),dietary fiber(37%),iron(121%),manganese(120%),phosphorus(101%) and severalB vitamins, includingfolate(94%) (table). High contents also exist forvitamin K,magnesium,zincandpotassium.
For human consumption, soybeans must be processed prior to consumption–either by cooking, roasting, or fermenting–to destroy thetrypsin inhibitors(serine protease inhibitors).Raw soybeans, including the immature green form, are toxic to allmonogastricanimals.
Most soy protein is a relatively heat-stable storage protein. This heat stability enables soy food products requiring high temperature cooking, such astofu,soy milkandtextured vegetable protein(soy flour) to be made.Soy proteinis essentially identical to the protein of otherlegumeseeds andpulses.
Soy is a good source of protein for vegetarians andvegansor for people who want to reduce the amount of meat they eat, according to theUS Food and Drug Administration:
Although soybeans have high protein content, soybeans also contain high levels ofprotease inhibitors, which can prevent digestion.Protease inhibitors are reduced by cooking soybeans, and are present in low levels in soy products such astofuandsoy milk.
TheProtein Digestibility Corrected Amino Acid Score(PDCAAS) of soy protein is the nutritional equivalent of meat, eggs, andcaseinfor human growth and health. Soybean protein isolate has abiological valueof 74, whole soybeans 96, soybean milk 91, and eggs 97.
Allspermatophytes, except for the family of grasses and cereals (Poaceae), contain 7S (vicilin) and 11S (legumin) soy protein-like globulin storage proteins; or only one of theseglobulinproteins. S denotesSvedberg, sedimentation coefficients. Oats and rice are anomalous in that they also contain a majority of soybean-like protein.Cocoa, for example, contains the 7S globulin, which contributes to cocoa/chocolate taste and aroma,whereas coffee beans (coffee grounds) contain the 11S globulin responsible for coffee's aroma and flavor.
Vicilin and legumin proteins belong to thecupin superfamily, a large family of functionally diverse proteins that have a common origin and whose evolution can be followed from bacteria to eukaryotes including animals and higher plants.
2Salbuminsform a major group of homologous storage proteins in manydicotspecies and in somemonocotsbut not in grasses (cereals).Soybeans contain a small but significant 2S storage protein.2S albumin are grouped in theprolaminsuperfamily.Other allergenic proteins included in this 'superfamily' are the non-specificplant lipid transfer proteins,alpha amylase inhibitor,trypsin inhibitors, and prolamin storage proteins of cereals and grasses.
Peanuts, for instance, contain 20% 2S albumin but only 6% 7S globulin and 74% 11S.It is the high 2S albumin and low 7S globulin that is responsible for the relatively low lysine content of peanut protein compared to soy protein.
The principal solublecarbohydratesof mature soybeans are the disaccharidesucrose(range 2.5–8.2%), the trisaccharideraffinose(0.1–1.0%) composed of one sucrose molecule connected to one molecule ofgalactose, and the tetrasaccharidestachyose(1.4 to 4.1%) composed of one sucrose connected to two molecules of galactose.While theoligosaccharidesraffinose and stachyose protect the viability of the soybean seed from desiccation (see above section on physical characteristics) they are not digestible sugars, so contribute toflatulenceand abdominal discomfort in humans and othermonogastricanimals, comparable to the disaccharidetrehalose. Undigested oligosaccharides are broken down in the intestine by native microbes, producing gases such ascarbon dioxide,hydrogen, andmethane.
Since soluble soy carbohydrates are found in thewheyand are broken down during fermentation, soy concentrate, soy protein isolates, tofu, soy sauce, and sprouted soybeans are without flatus activity. On the other hand, there may be some beneficial effects to ingesting oligosaccharides such as raffinose and stachyose, namely, encouraging indigenousbifidobacteriain the colon against putrefactive bacteria.
The insoluble carbohydrates in soybeans consist of the complex polysaccharidescellulose,hemicellulose, andpectin. The majority of soybean carbohydrates can be classed as belonging todietary fiber.
Raw soybeans are 20% fat, includingsaturated fat(3%),monounsaturated fat(4%) and polyunsaturated fat, mainly aslinoleic acid(table).
Withinsoybean oilor thelipidportion of the seed is contained fourphytosterols:stigmasterol,sitosterol,campesterol, andbrassicasterolaccounting for about 2.5% of the lipid fraction; and which can be converted intosteroid hormones.Additionally soybeans are a rich source ofsphingolipids.
Soy containsisoflavones—polyphenoliccompounds, produced by legumes including peanuts andchickpeas. Isoflavones are closely related toflavonoidsfound in other plants, vegetables and flowers.
Soy contains thephytoestrogencoumestans, also are found in beans and split-peas, with the best sources being alfalfa, clover, and soybean sprouts.Coumestrol, an isoflavonecoumarinderivative, is the only coumestan in foods.
Saponins, a class of naturalsurfactants(soaps), are sterols that are present in small amounts in variousplant foods, including soybeans, otherlegumes, and cereals, such as oats.
The following table shows the nutrient content of green soybean and other major staple foods, each in respective raw form on adry weight basisto account for their different water contents. Raw soybeans, however, are not edible and cannot be digested. These must be sprouted, or prepared and cooked for human consumption. In sprouted and cooked form, the relative nutritional and anti-nutritional contents of each of these grains is remarkably different from that of raw form of these grains reported in this table. The nutritional value of soybean and each cooked staple depends on the processing and the method of cooking: boiling, frying, roasting, baking, etc.
Soybean seed contains 18–19% oil.To extract soybean oil from seed, the soybeans are cracked, adjusted for moisture content, rolled into flakes, and solvent-extracted with commercial hexane.The oil is then refined, blended for different applications, and sometimes hydrogenated. Soybean oils, both liquid and partially hydrogenated, are exported abroad, sold as "vegetable oil," or end up in a wide variety of processed foods.
Soybean meal, or soymeal, is the material remaining after solvent extraction of oil from soybean flakes, with a 50%soy proteincontent. The meal is 'toasted' (amisnomerbecause the heat treatment is with moist steam) and ground in ahammer mill. Ninety-seven percent of soybean meal production globally is used as livestock feed.Soybean meal is also used in somedog foods.
One of the major uses of soybeans globally is as livestock feed, predominantly in the form of soybean meal. In the European Union, for example, though it does not make up most of the weight of livestockfeed, soybean meal provides around 60% of the protein fed to livestock.In the United States, 70 percent of soybean production is used for animal feed, with poultry being the number one livestock sector of soybean consumption.Spring grassesare rich in omega-3 fatty acids, whereas soy is predominantly omega-6. The soybean hulls, which mainly consist of the outer coats of the beans removed before oil extraction, can also be fed to livestock and whole soybean seeds after processing.
In addition to their use in livestock feed, soybean products are widely used for human consumption. Common soybean products includesoy sauce,soy milk,tofu,soy meal,soy flour,textured vegetable protein(TVP),soy curls,tempeh, soylecithinandsoybean oil. Soybeans may also be eaten with minimal processing, for example, in the Japanese foodedamame(枝豆,edamame), in which immature soybeans are boiled whole in their pods and served withsalt.
In China, Japan, Vietnam andKorea, soybean and soybean products are a standard part of the diet.Tofu(豆腐dòufu) is thought to have originated in China, along withsoy sauceand several varieties ofsoybean pasteused as seasonings.Japanese foods made from soya includemiso(味噌),nattō(納豆),kinako(黄粉) andedamame(枝豆), as well as products made with tofu such asatsuageandaburaage. In China, whole dried soybeans are sold in supermarkets and used to cook various dishes, usually after rehydration by soaking in water; they find their use in soup or as a savory dish. InKorean cuisine, soybean sprouts (콩나물kongnamul) are used in a variety of dishes, and soybeans are the base ingredient indoenjang,cheonggukjangandganjang. In Vietnam, soybeans are used to make soybean paste (tương) in the North with the most popular products aretương Bần,tương Nam Đàn,tương Cự Đàas a garnish forphởandgỏi cuốndishes, as well as tofu (đậu hũorđậu phụortàu hũ), soy sauce (nước tương), soy milk (nước đậuin the North orsữa đậu nànhin the South), andđậu hũ nước đường(tofu sweet soup).
Soy flour refers to soybeans ground finely enough to pass through a 100-mesh or smaller screen where special care was taken during desolventizing (not toasted) to minimizedenaturationof the protein to retain a highprotein dispersibility index, for uses such asfood extrusionoftextured vegetable protein.It is the starting material for soy concentrate and protein isolate production.
Soy flour can also be made by roasting the soybean, removing the coat (hull), and grinding it into flour. Soy flour is manufactured with different fat levels.Alternatively, raw soy flour omits the roasting step.
Soy lecithincan be added (up to 15%) to soy flour to make lecithinated soy flour. It increases dispersibility and gives it emulsifying properties.
Soy flour has 50% protein and 5% fiber. It has higher levels of protein, thiamine, riboflavin, phosphorus, calcium, and iron thanwheat flour. It does not containgluten.As a result,yeast-raisedbreadsmade with soy flour are dense in texture. Among many uses, soy flour thickens sauces, preventsstalingin baked food, and reduces oil absorption during frying. Baking food with soy flour gives it tenderness, moistness, a rich color, and a fine texture.
Soy grits are similar to soy flour, except the soybeans have been toasted and cracked into coarse pieces.
Kinakois a soy flour used inJapanese cuisine.
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Soy-basedinfant formula(SBIF) is sometimes given to infants who are not being strictly breastfed; it can be useful for infants who are either allergic to pasteurized cow milk proteins or who are being fed avegandiet. It is sold in powdered, ready-to-feed, and concentrated liquid forms.
Some reviews have expressed the opinion that more research is needed to determine what effect the phytoestrogens in soybeans may have on infants.Diverse studies have concluded there are no adverse effects in human growth, development, or reproduction as a result of the consumption of soy-based infant formula.One of these studies, published in theJournal of Nutrition,concludes that there are:
Soybeans can be processed to produce a texture and appearance similar to many other foods. For example, soybeans are the primary ingredient in manydairy productsubstitutes (e.g.,soy milk,margarine, soy ice cream,soy yogurt,soy cheese, and soy cream cheese) and meat alternatives (e.g.veggie burgers). These substitutes are readily available in most supermarkets. Soy milk does not naturally contain significant amounts of digestiblecalcium. Many manufacturers of soy milk sell calcium-enriched products, as well.
Soy products also are used as a low-cost substitute for meat and poultry products.Food service, retail and institutional (primarily school lunch and correctional) facilities regularly use such "extended" products. The extension may result in diminished flavor, but fat and cholesterol are reduced. Vitamin and mineral fortification can be used to make soy products nutritionally equivalent to animal protein; the protein quality is already roughly equivalent. The soy-based meat substitutetextured vegetable proteinhas been used for more than 50 years as a way of inexpensively extendingground beefwithout reducing its nutritional value.
The soybean is used to make a product called soynut butterwhich is similar in texture to peanut butter.
Sweet-boiled beans are popular in Japan and Korea, and the sweet-boiled soybeans are called "Daizu noNimame[ja]" in Japan and Kongjorim (Korean:콩조림) in Korea. Sweet-boiled beans are even used in sweetened buns, especially inMame Pan[ja].
The boiled and pasted edamame, calledZunda[ja], is used as one of theSweet bean pastesinJapanese confections.
Roasted and ground soybeans can be a caffeine-free substitute forcoffee. After the soybeans are roasted and ground, they look similar to regular coffee beans or can be used as a powder similar to instant coffee, with the aroma and flavor of roasted soybeans.
Soybeans with black hulls are used in Chinese fermented black beans,douchi, not to be confused withblack turtle beans.
Soybeans are also used in industrial products, including oils, soap, cosmetics,resins, plastics, inks, crayons,solvents, and clothing. Soybean oil is the primary source ofbiodieselin the United States, accounting for 80% of domestic biodiesel production.Soybeans have also been used since 2001 as fermenting stock in the manufacture of a brand ofvodka.In 1936, Ford Motor Company developed a method where soybeans and fibers were rolled together producing a soup which was then pressed into various parts for their cars, from the distributor cap to knobs on the dashboard. Ford also informed in public relation releases that in 1935 over five million acres (20,000 km) was dedicated to growing soybeans in the United States.
According to theAmerican Cancer Society, "There is growing evidence that eating traditional soy foods such as tofu may lower the risk of cancers of the breast, prostate, or endometrium (lining of the uterus), and there is some evidence it may lower the risk of certain other cancers." There is insufficient research to indicate whether taking soydietary supplements(e.g., as a pill or capsule) has any effect on health or cancer risk.
As of 2018, rigorous dietaryclinical researchin people with cancer has proved inconclusive.
Although considerable research has examined the potential for soy consumption to lower the risk ofbreast cancerin women, as of 2016 there is insufficient evidence to reach a conclusion about a relationship between soy consumption and any effects on breast cancer.A 2011meta-analysisstated: "Our study suggests soy isoflavones intake is associated with a significant reduced risk of breast cancer incidence in Asian populations, but not in Western populations."
Reviews of preliminary clinical trials on people withcolorectalorgastrointestinal cancersuggest that soy isoflavones may have a slight protective effect against such cancers.
A 2016 review concluded that "current evidence fromobservational studiesand small clinical trials is not robust enough to understand whether soy protein orisoflavonesupplements may help prevent or inhibit the progression ofprostate cancer."A 2010 review showed that neither soy foods nor isoflavone supplements alter measures of bioavailabletestosteroneorestrogenconcentrations in men.Soy consumption has been shown to have no effect on the levels and quality ofsperm.Meta-analyseson the association between soy consumption and prostate cancer risk in men concluded that dietary soy may lower the risk of prostate cancer.
TheFood and Drug Administration(FDA) granted the following health claim for soy: "25 grams of soy protein a day, as part of a diet low insaturated fatandcholesterol, may reduce the risk ofheart disease."One serving, (1 cup or 240 mL) of soy milk, for instance, contains 6 or 7 grams of soy protein.
AnAmerican Heart Association(AHA) review of a decade long study of soy protein benefits did not recommendisoflavonesupplementation. The review panel also found that soy isoflavones have not been shown to reduce post-menopausal "hot flashes" and the efficacy and safety of isoflavones to help prevent cancers of the breast, uterus or prostate is in question. AHA concluded that "many soy products should be beneficial to cardiovascular and overall health because of their high content ofpolyunsaturated fats, fiber, vitamins, and minerals and low content of saturated fat".Other studies found that soy protein consumption could lower theconcentrationoflow-density lipoproteins(LDL) transporting fats in the extracellular water tocells.
Plantlignansare associated with high fiber foods such as cereal brans and beans are the principal precursor to mammalian lignans which have an ability to bind to human estrogen sites. Soybeans are a significant source of mammalian lignan precursorsecoisolariciresinolcontaining 13–273 μg/100 g dry weight.
Soybeans and processed soy foods are among the richest foods in totalphytoestrogens(wet basis per 100 g), which are present primarily in the form of theisoflavones,daidzeinandgenistein.Because most naturally occurring phytoestrogens act asselective estrogen receptor modulators, or SERMs, which do not necessarily act as direct agonists of estrogen receptors, normal consumption of foods that contain these phytoestrogens should not provide sufficient amounts to elicit a physiological response in humans.The major product of daidzein microbial metabolism isequol.Only 33% of Western Europeans have amicrobiomethat produces equol, compared to 50–55% of Asians.
Soy isoflavones—polyphenoliccompounds that are also produced by other legumes like peanuts andchickpeas—are under preliminary research. As of 2016, nocause-and-effectrelationship has been shown inclinical researchto indicate that soy isoflavones lower the risk of cardiovascular diseases.
Soybeans containphytic acid, which may act as achelating agentand inhibit mineral absorption, especially for diets already low in minerals.
Although observations of soy consumption inducinggynecomastiaon menare not conclusive,a pejorative term, "soy boy", has emerged to describe perceived emasculated young men withfemininetraits.
Soybeanfuturesare traded on theChicago Board of Tradeand have delivery dates in January (F), March (H), May (K), July (N), August (Q), September (U), November (X).
They are also traded on other commodity futures exchanges under different contract specifications: