The History of the Soybean
Native to China, the Chinese first cultivated the wild soybean 3,000 years ago. It took them nearly 1,000 years to develop its full nutritional potential. In the West it took only 30 years to turn soy into soy burger. Here we look at the soybean’s ancient roots and many uses in food today.
The Whole Bean Story
Soy Milk Skim
Salty Black Beans
Soy to the World
Mung beans, azuki beans, broad beans, green beans, peas; the Chinese make liberal use of all of them, but none of these legumes compare in significance to the one they call the ‘great legume,’ or the ‘yellow legume’ (though not all soy beans are yellow), the one we know as the soybean. In fact the soybean is so central to the Chinese food system that it is often simply referred to as ‘the legume,’ its full name only deemed necessary when distinguishing it from other types. So when Chinese buy tofu they need only ask for doufu. Rotten Legume, Likewise soy milk is rendered dou jiang, ‘legume paste.’
The soybean differs from its legume cousins in its lower level of carbohydrate, but much higher tallies of protein and oil. After rice and wheat, the great modern-day staples of China, the soybean sits firmly on the third rung on the Chinese food hierarchy. From a dietary point of view soy food offers a ton of protein and calcium to a population that gets precious little of either from meat or dairy products. Though it is not usually consumed in large quantities, except by vegetarians, soy in one form or another is eaten daily by just about everybody. Soy sauce alone, with its role as a key food flavouring, would be enough to guarantee that much. Let’s have a look at how the soybean became soy food.
Native to north-east China (Manchuria), the soybean (Glycine max) was cultivated some 3,000 years ago. The plant’s wild precursor was a recumbent vine, Glycine max. During the early centuries of domestication, the soybean was nothing like as important in the Chinese diet as it is today. In fact it may well have been far more useful as a fertiliser than as a food – ploughed back into the soil to enriching it for other crops such as wheat or millet. The soy plant is fortunate to be a member of a family of plants that has the ability to draw nitrogen from the air impart it into the soil through its roots thus enriching poor soils. Soybean plants may also have been rotated with other crops, for this same purpose.
But while those ancient farmers had discovered a new food source, only their descendants, almost 1,000 years in the future would begin to fully understand the nutritional value of the soybean. The long history of domestication resulted in a great variety of upright hardy soy plants that do well in a wide range of soil and weather conditions.
The main types of soybeans are categorised by seed colour: green, black and by far the most common, yellow, the variety that inspired the bean’s other name, Yellow Legume, Huang Dou.
Like grain such as wheat or barley, mature soybeans are normally harvested dry and hard on the plant. During the Zhou Dynasty (1050–256 BC), soybeans were designated one of the Five Sacred Grains (the others being wheat, barley, rice and millet). Then the soybean was known as shu, and boiled beans were eaten whole. The leaves of the plant were also eaten. But whole soybeans then as now were hardly considered a delicacy. At that time millet was the preferred grain, followed by rice, wheat, and soybeans at a less than mouth-watering fourth place.
The migration of the soybean from northeast China was gradual. By the first century A.D. it had spread to central and south China, and Korea. Sometime after this date and before the arrival of the Europeans in the 16th century, soybeans were sown in Japan and South East Asia. Today northeast China is still the major soy belt of China.
When it comes to the art of survival, the Chinese seem to have always been ruthlessly efficient exploiters of the environment. The regimen with the soybean was no exception. The bean turned out to be a very cheap source of protein, yielding much more by acreage than milk, eggs or meat, or other common crops. At around 37 per cent by weight, the pea-size soybean is loaded with protein. That figure means the soybean thrashes any other plant source, and even meat at 15–20 per cent, And the protein that soybeans offer is top quality. The amino acid balance is almost as good as in meat. The soybean still plays a tremendous role in supporting a large population on limited arable land. But this has not always been the case. All this wonderful nutrition was hard won, for once they have initially tamed the soybean plant, it would take the Chinese another 1,000 years to fully unlock the nutritional potential of their humble yellow bean.
The Whole Bean Story: Why Soybeans are Not Eaten Like Other Beans
It took so long because there are a couple of major problems with soybeans; the first, as already mentioned, a matter of taste, the second, one of nutrition. Even after lengthy boiling, soybeans remain quite tough and beany, and taste a little bitter. More importantly, due to a digestive enzyme called trypsin which interferes with protein that digestion, whole soybeans are largely indigestible. They do however contain some useful vitamins and minerals that are digestible, but most of the protein they contain just passes through the system with barely a blimp on the nutritional radar screen. It is this fact which explains why unlike other beans and peas, soybeans are seldom eaten whole today. The generations that followed the Zhou Dynasty, learned that to more fully exploit the protein, the soybean needed to be processed further.
Making soy milk was one of the early methods. Soy milk is nothing more than a milky liquid that results from boiling and mashing whole beans, so we can assume that it was not long before soy milk was ‘invented.’ Initially it may have been eaten as bean meal soup. Even today in China soy milk remains a drink that is processed and consumed in simple ways, though it is often sweetened and occasionally salted.
In soy milk processing, the Chinese were perhaps inspired by their nomadic, animal-herding, milk-guzzling northern neighbours, the Mongols. Some scholars recognise this possibility. Soy milk after all looks like, (but certainly does not taste like) dairy milk. And like that drawn from the cow’s udder, it is mainly consumed by the Chinese for breakfast.
Traditionally the Chinese have never fed soy milk to infants. Babies were breast fed, by a wet nurse if necessary. But as in many countries, breast feeding rates have dropped greatly over recent years. Many mothers have the mistaken belief that milk formulas are more nutritious than breast milk, If you visit any supermarket in China today you will find an aisle stacked full of dairy-based powdered formulas, just as in any western supermarket.
Soy Milk Skim
Soy milk soon gave a natural rise to dou pi, tofu skin, the dried skim from boiled soy milk. Although it is very like dried tofu, technically speaking it is not the same. Soy milk skim is used in similar ways to dried tofu and is easily mistaken for it.
Salty Black Beans
Fermentation improves the digestibility of soy protein. Salty black beans, the first known fermented soybean product, were a not only an early nutritional breakthrough, but one for the taste buds too. It occurred, accidentally or otherwise sometime during the late Zhou Dynasty or the Han Dynasty (206 BC–220 AD) that followed. The salty black beans (the black colour is the result of the process), used today in Chinese cooking differ little from those early fermentation experiments. What is perhaps most significant is that black beans were the forerunner of what is essentially their liquified equivalent, soy sauce.
Fermented soy in sauce form proved to be much more versatile than salty black beans.
Nearly all soy products include the word dou in their name. But you won’t find that character on any bottle of soy sauce. Instead what you find on the label are the characters jiang you. This translates as sauce oil. This is a little odd as most other Chinese sauces are referred to as jiang, as in la jiao jiang – chilli sauce, and anyone who ever fumbled with a pair of chopsticks knows that soy sauce is not oily (though there are some very oily soy pastes available). So why is soy sauce called sauce oil? First let’s talk about the first word jiang. It is nearly certain soybeans were neither the first or the only vegetable or meat to be fermented into a sauce. All fermented sauces in ancient times were collectively called jiang, regardless of the what they were made from. Now to the second word, you. It usually means oil. But probably what the early sauce makers meant by you was extract – a sauce extracted from the beans.
No one knows exactly when soy sauce was first formulated. What we do know is that during the Song Dynasty (960–1279) the character jiang came to refer strictly to one type of sauce only, soy. By the late southern Song, a phrase was coined that became famous: “The things that people cannot do without everyday are firewood, rice, oil, salt, soy sauce, vinegar, and tea.” Soy sauce by then had already become one of the great flavours of China.
Made in the traditional way soy sauce as we are familiar with it today, is fermented naturally from soybeans, wheat flour, salt and water, a quite sophisticated and time consuming process, that might take anywhere from six months to two years.
Also worth noting is that because of its high salt content the use of soy sauce almost makes the use of salt cooking redundant. For this reason plain salt has drastically less importance in Chinese cuisine than it does in a great many other cuisines. Soy sauce is also commonly used as a preservative. Its nutritional value should not be dismissed either as it is a good daily source of Riboflavin, Vitamin B6, Magnesium and Copper, and is packed with Protein, Niacin, Iron, Phosphorus and Manganese.
The invention of soy sauce changed the taste of Chinese food forever. It remains the quintessential Chinese seasoning.
Soybeans contain vitamins and minerals but little vitamin C. But sprout some beans in a warm corner of your kitchen, something done incredibly quickly (1-1/2 to 2-1/2 days) and easily, and they begin sprouting vitamin C in decent doses. A useful thing to know at anytime but particularly during northern China’s bitter winters, when until recent times fresh vegetables and fruit were hard to come by. How long the Chinese have been eating bean sprouts is difficult to say, but as sprouting occurs in nature without human intervention, the process would have been noticed early on. Basically it is through overseas Chinese restaurants that sprouts have become familiar in the western world. But the Chinese, it should be noted, do not eat sprouts raw. Cooking sprouts releases a protein not available in the raw state. Cooking increases the nutrient value of sprouts, besides making them more palatable.
While soybeans are grown primarily for their protein, they are an important source of edible oil too. They are one of the major oilseeds, containing as they do about 18% fat, a much more than other legumes (chick peas for example, lag way behind with 5%). The sheer volume of this cholesterol-free oil coupled with its mild flavour help explain why soy oil is the most popular cooking oil in the world today. In China though, it runs second to rapeseed oil, but ahead of peanut oil in third place.
As we know, Chinese do not consume the soybean whole. Here we have to qualify that statement – unless it is green. Edamame (a Japanese term) soybeans are mature but still green beans picked before they dry on the plant. In this form the three beans the pods hold are partially digestible. Certain varieties of soybean are considered more suitable for this. They are used as a vegetable in stir-fried and braised dishes or eaten directly from their hairy pods as a snack, hence the name mao dou or hairy bean. A spicy version cooked in black pepper, garlic and star anise is popular in Taiwan tea shops.
It was tofu that finally cemented the soybean’s role in Chinese cuisine. If rice and wheat are the carbohydrate cannons, tofu put loads of previously unavailable cheap protein on the table. Legend has it that tofu was discovered by Liu An (179–122 BC), the Prince of Huainan, grandson of the founder of the Western Han Dynasty, Liu Bang. A key element of Taoism of the time was alchemy, and Liu An was a practitioner of this art, the forerunner of modern chemistry. Liu An, the story goes created tofu in search for immortality or at least longevity. Scholars think the very first tofu was made by adding salt to a batch of soy milk. When curds formed, a new solid food was born. Whether or not Liu An was really the first ‘curdler,’ Huainan in central Anhui Province manages to attract plenty of people to the tofu festival it holds every September 15, largely on the basis of the story.
Until fairly recently the earliest evidence of tofu was from the Tenth Century Sung Dynasty when tofu first receives a substantial mention in literature. If you have been keeping track of of our timeline, that would mean that it took the Chinese 2,000 years to learn how to make tofu. Somehow this never seemed to ring true. As is often the case in history, one truth is superseded by another. Archaeological evidence from a 1980 dig in Dahuting, Henan Province pushes the existence of tofu back at least 750 years. The excavated Han Dynasty (A.D. 25–220) tomb revealed a stone slab with a mural featuring a kitchen scene which illustrates the making of soy milk and tofu.
Tofu has more than protein to offer. Soy milk though very healthy contains only a fairly miniscule amount of calcium, but when *Gypsum (Hydrated Calcium Sulphate), a harmless mineral long used in the making of plaster, is added as a coagulating agent, soy milk is transformed into calcium-rich tofu. This is a vital boost for the vast majority of Chinese who have rarely, if ever had dairy foods in their diet.
The role of tofu in the Chinese diet has been likened to that of meat and milk in other cultures. This analogy is often pushed too far by the soy industry and various health ‘gurus,’ but is far from completely ridiculous. Aside from the nutritional package it delivers, the brilliance of tofu lies in its versatility as it can be prepared in a multitude of ways and blends well with many other foods. Though bland in its basic form, any half-decent Chinese cook knows how to make any number of delicious dishes with this silky white curd. And unlike the fermented seasonings and sprouts that had come before it (the unappetising whole beans notwithstanding), with tofu, here was an economical food of substance, one that could fill the gut. It was also a food Buddhists could love and they in fact were largely responsible for its spread to the far flung borders of China and beyond.
Two thousand years ago when two Buddhists missionaries named Kasyapa and Dharmaraksha arrived from India after a long journey on the Silk Road, they brought with them a belief in the virtuousness of the meatless diet. Their teachings eventually found an a receptive audience – meat was a luxury the Chinese peasant could rarely indulge in, and for some the gap between a diet of little meat, and of no meat was not a wide one. The great Chinese art of meat substitution was born. Meat analogues can be amazingly meat-like. And mock meat could be eaten guilt-free, and it was much cheaper than the stuff hacked from the carcasses of animals, which meant that you could eat more of it, more often. In time tofu and soy protein played a central role in the making of meat substitutes. Whether made of tofu, soy protein, wheat gluten or mushrooms, mock meat remains a major feature at vegetarian restaurants and temple kitchens throughout China and Taiwan.
Soy to the World
Although its basic nutritional talents were known, early attempts to get Americans and Europeans eating soy largely failed, though soy sauce found a market as a general seasoning after being imported to Europe by Dutch traders in the 17th Century. The Americans, however had no such trouble getting cattle, pigs and chickens to gobble up soy meal, thus creating a huge soy stock feed industry. Many industrial uses for soy were also found throughout the 20th Century.
Apart from perhaps buying the odd bottle of soy oil, it was in Chinatown or at the local Chinese restaurant where most Westerners first encountered soy food – soy sauce, tofu and bean sprouts. But soy food has been in the ascendancy since the 1970s when it became the darling of vegetarians after belated recognition as a miracle health food. Since then soy has worked its way into thousands of food products, often for reasons of economy rather than health, while soy protein has become the basis for a whole range of western meat product substitutes, many sophisticated, some rather bizarre.
In the 1950s America overtook China in soybean production. These days China imports large quantities of soybeans and its by-products from America, The Chinese, not surprisingly, have yet to develop a taste for the soy burger.
*Other coagulating agents can and have been used. Salt was perhaps the earliest.
More information about Chinese soy products
Soy Food in Chinese Cuisine – Eating China
Deliciously Malodorous: Chinese Stinky Tofu – Eating China
A Comprehensive History of Soy – Soyinfo Center
Try these Chinese soy recipes
Deep Fried Tofu