Soybeans
edamame (Japanese)
(Glycine max or Glycine soja -- Family Leguminosae)
The soybean has been a staple food in the Far East for over 5,000 years. It is thought to have been the plant that the Chinese emperor Shen Nung used to introduce his people to the art of cultivation and the one he mentioned in his Materia Medica, dating from about 2900 BCE. Although it has been cultivated and eaten by the Chinese for thousands of years, it did not find its way to Japan until the 6th century CE and to Europe in the 17th century, but not until after WWII did their extraordinary nutritive value become known. Soybeans were first known in Europe through Engelbert Kaempfer, a physician to the governor of the Dutch East India Company on an island off Japan in 1690. Since the Japanese guarded their culture, it was difficult to obtain plants, seeds, or information; but, after bribing guards and picking plants along the way, Kaempfer was able to obtain his botanical specimens and took some seeds to Europe in 1692.
Various attempts were made to establish it as a crop plant in both Europe and America. It achieved some success in India, where it was known as the white gram. When Benjamin Franklin was in France, he sent it to North America in the late 18th century. By 1829, soybeans were grown at Cambridge, Massachusetts, and were considered a luxury. One of the first Americans to be interested in soybeans was Henry Ford, who saw their potential for manufactured goods. Ford is said to have eaten soybeans at every meal and had a suit made from soy fabric. So enthused was he about the bean, that he sponsored a 16-course soybean dinner at the 1934 "Century of Progress" show in Chicago.
Soybeans can provide all the nutrients humans need to survive; containing up to 48% protein, about 11% carbohydrates, and 18% valuable essential fatty acids. Their high quality, complete protein is far more than any other plant supplying a full and well-balanced mixture of all the essential amino acids. The bean contains more than 100% of the dietary requirments of lysine, methionine, cystine, threonine, and tryptophan. Their protein content rivals that of meat, but much easier to digest and assimilate. One cup of cooked soybeans yields twenty-two grams of protein, which is about the same as a three to three and one-half ounce serving of meat, fish, or poultry. They are a good source of lecithin, vitamins A, B, E, potassium, and phosphorus. The oil content of the soybean can be up to 34% and is the world's main source of cooking oil. However, it is the hardest of beans and requires long periods of soaking and cooking.
North America is the biggest producer and exporter of soybeans; but other important growers are China, India, Indonesia, the Philippines, Africa, Central and South America, and Russia. On a worldwide scale, the soybean is the most important legume. There are more than 1,000 varieties of soybeans, ranging in size from a pea to that of a cherry. They also come in a rainbow of colours: red, black, yellow, brown, blackish, and green. The soy plant is considered to be an annual herb that grows from eight to forty inches in height, producing trilobed leaves and white to pale violet flowers. The hairy, yellow-gray or black shells, contain two to five round or flat seeds and mainly found on the lower parts of the stem. The crop is harvested before the pods burst open. Some varieties include: Black Jet, Fiskeby V (a yellow bean), Hakucho Early (a dwarf Japanese variety producing three small seeds per pod), Lammer's Black (the best bean for short seasons), Maple Arrow (grown mainly for processed products), and Prize (good for sprouting).
From the soybean comes a wide variety of food products including the following:
Chinese brown and yellow bean paste is made from fermented soybeans and available under many different names and types throughout China. The pastes are used mainly as a condiment. Hot bean paste is just that --hot -- but it is also lumpy and used to perk up sauces. Sweet bean paste is a smoother, sweeter variation used in both marinades and sauces.
Fermented Black Soy Beans: is a strongly flavoured, highly salted, product used frequently in Chinese cuisine. These beans are made from small soybeans, and not the black turtle beans, and preserved in salt before packing. The pungent, salty flavour is overpowering to some, so the beans are rinsed before they are used. The Koon Chun brand, sold in plastic bags from Hong Kong, adds orange rind, ginger, and garlic. These spicy additions can also be added to cheaper, plain salted beans as well.
Miso: is a fermented, concentrated bean paste. It was first mentioned in an ancient Chinese writing, dating about 200 BCE. Dou jiang is the Chinese equivalent. No matter where it is made, miso is typically made in two stages. First a mold, Aspergillus oryzae, is grown on steamed grain (usually wheat, barley, or rice) which forms the starter culture (koji). The beans are soaked, steamed, chopped, and mixed with koji, salt, and water containing yeasts and lactic bacteria, which will eventually develop the final flavour. This mixture is then left to ripen for as long as required, usually anywhere from six months to three years. Tsugaru-sannen miso is one type that is fermented for three years. When the fermentation is complete, the soya beans have retained their original shape.
Miso used to be ground daily at home with a pestle; but today, it is sold already ground. The lighter kinds of miso are more quickly fermented and milder in flavour. The darker ones are stronger and more mature. The colours range from white, or a pale yellow, through to red and brownish-black. Sweet and salty types are also available, but the dark kind is always salty. A large amount of salt is needed in colder climates, where fermentation is slow, in order to keep the beans from going bad before the fermenting organism takes hold. Miso will keep refrigerated for up to a year and is used primarily in soups and as a basic flavouring for Japanese cooking.
There is a related product that may be considered an early form of miso similar to the Chinese fermented black beans. Hamanatto is a specialty of Shizuoka and made like miso, but with the addition of toasted, ground wheat to the beans. Dried in the sun and mixed with ginger, the final product is black with a sweet taste. Another similar product, tauco kering, has been introduced in Indonesia.
There are four general types of Miso made from the following:
-- Rice and soybeans is a light yellow, relatively sweet, and called komemiso. It can also come in a variety of colours because of different ingredients used and methods of fermentation.
-- Barley or rye and soybeans is red and called mugimiso. One kind is hatcho miso which may take up to two years to mature. Barley miso may be either sweet or salty.
-- Soybean only, produces a thick, fudge brown miso called mamemiso. This type, good for winter soups, is very rich and salty and needs to be cut with a knife.
-- Blended types, include a kind made in Okinawa where the stones of cycads are used.
Natto is a different soya bean product that is fermented by bacteria (usually Bacillus subtilis) rather than molds. The bacteria gives the beans a whitish coating and a flavour and texture which not all Japanese appreciate, but Indonesians prefer. The flavour is strong, musty, and faintly smells of ammonia. The bacteria develop on the beans into a sticky slime which forms strings. The longer the strings the better the natto, according to natto authorities. It was often made at home by wrapping cooked soya beans in rice straw, supplying the necessary bacteria, and then left in a warm place for a day or two. Commercially prepared natto is innoculated with a pure bacterial culture.
Shoyu is a naturally fermented and aged, but mellow, soybean product.
Soy flour is the ground soybean and used in combination with other flours in baked goods. It is said that one tablespoon of soy flour can be used as a substitute for an egg in most baked goods. Its protein content is twice that of wheat.
Soy milk is a non-dairy substitute and higher in protein than milk, and contains no cholesterol. It is also low in fat and sodium, and rich in iron. This is the milk that is curdled to make tofu. The fat in soy milk is unsaturated, and only about one-third as much as that found in cow's milk, making it a good diet food. Soy milk is basically made by soaking the beans, grinding them with more water, bringing them to a boil, and then filtering the product.
Soy oil is made by compressing the bean. However, most soy oils are highly processed (see oil processing in the health section). Soya oil is also used in a wide range of products: ice cream, margarine, soaps, paint, milk substitutes, soy sauce, tofu, Worcestershire sauce, meat substitutes, and firefighting foam.
Soy sauce is the salty liquid made from fermented soybeans and roasted grain, usually wheat or barley, and hydrochloric acid to break down the bean. The remains are mixed with corn syrup, caramel colouring, and salt, then diluted with water to be used as a flavouring for many Chinese dishes. Soy sauce was used to prevent foods from spoiling in the summer heat and to preserve them for the winter months. Soy sauce was developed in China during the Zhou dynasty (1134-246 BCE). In the 15th century, Japan began to produce its own type of soy sauce; and, in the 16th century, it was commercially manufactured instead of being made by individual farm families for their own or local use. Interestingly, the soybean received its name from the sauce and not the other way round. The name "soy" is similar in all languages, and originated with 17th century Dutch traders, who brought the sauce back to Europe where it became popular inspite of its high price. Old silver bottle labels marked "soy" still sometimes appear in antique shops.
Soy sauce is made by fermenting boiled soybeans, roasted wheat or barley, and salt. There are several stages to the process. Fermentation is carried out by using many different molds, bacteria, and yeasts which successively predominate in the developing sauce as conditions change to suit them. Generally, the mixture is inoculated with a starter culture of two necessaryAspergillus molds (A. oryzae and A. soyae) and allowed to ferment. This is mixed with a strong salt solution and inoculated with another starter containing several kinds of bacteria and yeasts for a further fermentation which lasts eight to twelve months. This brine makes a liquidy mash, much like wort for beer. The reactions in this last period creates a complex blend of substances contributing to the final flavour. The chief elements are salt, amino acids, organic acids (lactic and acetic), alcohols, sugars, and numerous volatile aromatic substances, including vanillin, the principal flavour of vanilla. When fermentation is complete, the mixture is filtered or racked to extract the sauce, and pasteurized to kill any remaining organisms and arrest fermentation. There are, however, some special sauces whose fermentation is allowed to go on for years. On average, it takes one ton of defatted soy beans, wheat, and salt to produce 5,000 liters of soy sauce.
China and Japan produce many different kinds of soy sauce, including light, medium, dark, thin to thick, black soy, and mushroom soy. Chinese soy sauce is generally quite salty with a dense flavour. Japanese soy sauces have a relatively bright taste and aroma, but far more wheat is used to make them sweeter and less salty. Japanese sauces are generally lighter and thinner, while the Chinese soy sauces are darker and thick. Today, it is wise to check if the soy sauce is naturally brewed or not. Artificially brewed soy sauces, with Chinese-sounding names, are sold at lower prices and brewed with a chemical, taking only three or four days to ferment, rather than the one year brewing period. Artificially brewed brands list water, then salt, hydrolyzed soy protein, corn syrup, caramel colour, and potassium sorbate as the preservative. A naturally brewed brand will list water, then wheat and soybeans before salt, with less than 1/10th percent of sodium benzoate as a preservative.
Kikkoman is a widely available quality brand made in the US, that originally began producing soy sauce in Japan in 1630. In Japan, the standard is the light flavoured one in the Osaka region. It is amber in colour and saltier than the dark types. Black soy sauce is a concentrated product made with molasses. It is aged for an extra-long time and lasts indefinitely. Mushroom soy sauce is seasoned black sauce flavoured with dried Chinese black mushrooms. An Arab version of soy sauce, called murri, is made much the same way, but uses moldy barley rather than beans. This is sometimes extended with wheat flour or bread. Although available in light and dark, the most extreme of the dark types of soy sauce is the viscous Indonesian kecap made from black soy beans.
Soybean sprouts are one inch crisp sprouts that can be eaten in salads or on sandwiches. However, unlike mung beans, soybean sprouts must be blanched before they can be eaten.
Tamari is a wheat-free fermented sauce made from soybeans, salt, and water, and is a bit stronger in flavour than shoyu. It is the Japanese cousin of soy sauce often sold in health food stores. It is made mainly of soybeans and is cultured and fermented like miso. It is darker in colour than the standard type of soy sauce. Even in Japan, it is difficult to find a good quality tamari which is used as a dipping sauce or a foundation for a basting sauce.
Tempeh is similar to tofu, but sturdier and adaptable to many cooking techniques, including grilling, steaming, or frying. It is an ancient fermented food from Indonesia, made with split, cooked soybeans and a fungus starter (Rhizopus oryzae or R. oligosporus) to encourage fermentation. The starter is used like any starter, with some from the previous batch saved for the next one. The beans are traditionally wrapped in banana leaves and left to ferment. Tempeh became popular outside of Java only in the 20th century. It has 50% more protein than red meat and serves as a meat substitute for vegetarians.
It can be used during any of the four stages of fermentation.
-- Tempe koro is given four to six hours less ripening time than normal, giving a stiff underripe cake.
-- Tempe murni is the normal time of twenty-four to forty-eight hours, being the most commonly used form.
-- Tempe semangit is two or three days older than the normal.
-- Tempe busuk (rotten tempe) is three to five days older.
The mold gives the flavour and texture reminiscent of cheese. In fact, Tempe murni very much resembles Camembert, while the oldest form is like Stilton, being more crumbly and ammoniac in smell. Its enzymes also have a marinating, tenderizing effect on other foods when combined with them in other dishes. All forms of tempeh should be kept in their wrappings until needed as exposure to air causes the mold to grow out of control and turns the surface black.
Tofu is the custardlike cake made by curdling soy milk in a process similar to that used for cheese. Many believe that tofu-making was an adaptation of such, learned by the Mongols. However, this ancestry is in dispute as the first mention of tofu in Chinese writing did not take place until the 10th century CE, although a type of bean curd originated in China between 200 and 900 CE. The first reference to tofu in Japan was in the 12th century CE, which was the time period of the Zen Buddhists and their popular vegetarian tenets. However, it was probably only during the Edo period (early to 17th century to late 19th century) that tofu became fundamental to the diet of the ordinary Japanese citizen. Japanese tofu is softer and more delicately flavoured than the firmer Chinese-type.
Bean curd is made from dry soybeans that have been soaked in water until softened, then crushed and boiled. The crushed mash is separated into pulp (curds) and milk (whey), just as it is in the making of cheese. Methods of "curdling" involve the use of calcium sulphate, or by the traditional curdling agent called nigari in Japan. This "bittern" is the lye left over after the crystallization of salt from sea water. The curds are poured into molds and left to settle and take shape and then soaked in water to firm and keep cool and fresh. In Japan, small tofu cakes are cut from large blocks. Chinese bean curd cakes tend to be smaller, and excess moisture is often pressed out beforehand, allowing the Chinese stype to be sold dry in plastic bags rather than in water-packed containers of the Japanese form. The Japanese type cannot be successfully frozen without becoming chewy.
There are three main types of Japanese tofu:
-- Regular (momen or cotton tofu) is drained in cloth and has a slightly coarser texture than silken tofu.
-- Silken (kinu) is a soft tofu that has not been drained and cannot be pressed as it is quite delicate.
-- Yakidotu has been lightly broiled, giving it a light-brown mottling and a firm texture. It is packed in water.
Tofu appears in various forms, including fresh, freeze-dried, savoury, pickled, and smoked. Its shapes are also numerous: sheets, strips, shreds, knots, and noodles. However, out of all that, there are two fundamental fresh forms. One has a firmer texture, since some of the water is pressed out, and the other is soft like custard. Though extremely high in protein and low in cost, tofu is also very perishable and keeps for only a few days in the refrigerator. However, it is neutral enough that it can be combined with anything and taking on the flavour of stronger ingredients with which it is combined.
Yuba is the name for a Japanese delicacy consisting of the thin skin which forms on the surface of soy milk when it is heated in the preparation for making tofu. These skins are lifted off as they form and dried. When needed, they are reconstituted and used in soups or as wrappers. Although well-known in Japan, their popularity is greatest in China and Taiwan. The film is highly nutritious, having the richest protein source known (over 52%), natural sugars (12%), and polyunsaturated fats (24%), making it an ideal energy food. When the skins are dried and rolled up, they may be called "bamboo yuba" because of its resemblance to bamboo shoots.
