a white curd made from soya beans, originated in China as tou-fu (now dou fu). Tofu, the name commonly employed worldwide, is the Japanese adaptation of this. The product is also known as bean curd.
It has been said, with some justice, that tofu occupies a place in oriental cookery which corresponds to that of dairy products in other parts of the world. It exists in various forms which offer parallels to cheeses; and the similarity extends beyond appearance and use. The composition of tofu, a highly concentrated protein food, resembles that of cheese.
The proteins in soya beans, although abundant, are physically and chemically locked up in a manner which frustrates human digestion. Making the beans into tofu renders them more available. This is particularly important because tofu yields the essential amino acid lysine, which is lacking in the staple food of the region, rice.
The preparation of tofu, as practised now, begins with soaking the soya beans. They are then ground with added water, boiled, and filtered to produce a warm ‘milk’. This is curdled by calcium sulphate, or by a traditional curdling agent called nigari in Japan; this is bittern, the lye left over after the crystallization of salt from sea water. The curd is then ladled into boxes and pressed to squeeze out most of the remaining ‘whey’.
The similarity to cheese-making is striking. Indeed, some have thought that the manufacture of tofu was originally an adaptation of cheese-making, learned perhaps from the Mongols. However, questions about its origin are difficult to answer. Dr Yan-Kit So (1992) draws attention to work by a Japanese historian, with which many Chinese historians agree, which seems to establish that there is no significant mention of tofu in Chinese literature until the 10th century ad. This seems to rule out a traditional belief that the Chinese Lord Liu An of Hainan invented tofu in the 2nd century bc.
What is certain is that tofu arrived at an early date in Japan and has also been an important food in Korea since the distant past. The first recorded reference to tofu in Japan is from the 12th century ad, which was also the period when Zen Buddhism, with its vegetarian tenets, became popular there, a development which has no doubt favoured the use of tofu ever since. However, it was probably only during the Edo period (early 17th to late 19th century) that tofu became ordinary people's food in Japan and also came to be made much softer than the original kind.
Tofu is also important in other countries, e.g. the Philippines, where it is tokwa.
The number of different forms which tofu can take is very great. The book by Shurtleff and Aoyagi (1983) provides extensive information and explains the characteristics and particular uses of the various sorts. A few of them, including those most likely to be met and some of special interest, are listed below.
Plain tofu (doufu) in China is usually prepared in large squares, which are cut by the vendor to yield smaller squares of about 10 cm (4″) and 4 cm (1.5″) thick. This doufu, which is moderately firm, is often sold immersed in water in sealed containers.
Pressed tofu, doufu-kan, is also sold in squares, rather smaller, and has a meatier, more chewy texture. It may have added colour or flavour. The version called wu-hsiang kan is a sort of savoury pressed tofu, flavoured with five or more spices. It comes in various shades of brown and is described as resembling smoked ham.
The regular kind of tofu in Japan is momendofu, cotton tofu, with a surface marked by the weave of the cotton cloth in which it is wrapped to be pressed. It is less firm and contains more water than the regular Chinese doufu (to which Japanese pressed tofu is closer in these respects).
Kinugoshi, ‘silk tofu’, is a Japanese product which has a finer consistency, like silk (but neither silk nor cotton is used in its manufacture). It has its counterpart in China, sui-doufu. These are soft forms, usually too soft to be cut into pieces; instead they may be scooped into bowls, topped with a little soy sauce or sugar, and eaten with a spoon.
Freeze-dried tofu used to be made naturally, by taking advantage of freezing temperatures at high altitudes or night-time, but is now commercially manufactured. When reconstituted, it has a spongy consistency.
Tofu appears in numerous shapes: sheets of one kind or another, strips, shreds, knots, noodles, etc. Smoked tofu is also available, usually in small blocks of one form or another.
Deep-fried tofu in China appears under names such as doufu pok and cha-dofu. Abura-agè in Japan are deep-fried thin slices of tofu suitable for slitting open and making into pouches. Inari-zushi are these pouches filled with sushi rice, vegetables, mushrooms, etc.—a favourite picnic dish.
Ganmodoki is the name used in the Tokyo region for deep-fried tofu balls (kneaded with other ingredients, including a binder such as ground yam).
Yaki-dofu, pieces of tofu which have been grilled to produce a surface mottled with brown, and a texture which holds together well, are another Japanese item.
In China tofu is fermented to make various products, some of which are considered too smelly by western people (just as western blue cheeses are off-putting for people from the Orient). The generic term is doufu-ru. The most popular type is white doufu-ru, within which category are types spiced with minced chilli pepper or any of numerous other seasonings.
Red doufu-ru is deep red in colour and has a distinctive flavour, from the red fermented rice which is used in preparing it. It includes a variety flavoured with rose essence and sugar.
Tsao-doufu has an alcoholic aroma, betraying the rice wine and rice wine lees used in making it. A green version, ch'ou doufu, is popular in Taiwan, where it is considered a delicacy by those who like it, although others are repelled by its smell and appearance.
Chiang dou-fu are cubes of tofu fermented in soy sauce or Chinese-style miso. Reddish-brown and salty.
In the Philippines fermented soya bean curd is tausi.
An example of pickled tofu and of the many specialities in Japan is umesutsuke, tofu pickled in plum vinegar, with a purple exterior.
One important Chinese speciality, hardly known at all in Japan, is dofu nao. This is a very soft form, sometimes referred to as ‘smooth curds’. In fact, the Chinese name means literally ‘bean brain’, referring to the brain-like texture. It is treated like a sort of pudding, and vendors do a brisk trade in it from their carts. The scene is vividly described by Shurtleff and Aoyagi:
Customers seat themselves at stools around the cart and get ready for a hearty breakfast (costing less than 5 cents). The vendor ladles out scoops of custard-like curds into deep bowls, tops them with a warm syrupy sauce (hung t'ang) containing peanuts and brown sugar, and places them (together with porcelain spoons) on the edge of the cart, which serves as a table. In some areas the curds are mixed with cha-t'sai pickles, tiny dried shrimp, soy sauce, and a dash of sesame oil, then served as a thick soup. In others, they are mixed with sweet oil, vinegar, finely chopped meat, or spices.
In many of these forms tofu is made and bought daily. In Japan every village has its tofu shop, where work starts early in the morning, as in bakeries for bread in western countries. These shops may also sell soy milk, although there are often separate shops for that. yuba, which may appear in cookery books as ‘bean curd skin’ or ‘tofu skin’, has its own specialist shops or stalls, at which it appears in an astonishing range of imitative forms: poultry, fish, tripe, etc. Another product is okara, the ‘presscake’ (pulped skins of the soya beans) left over when the milk is made; highly nutritious but not so tasty. See also imitation foods.
There are also special tofu restaurants, where a varied meal consisting entirely of tofu in different forms may be had. The scope for cooking with tofu is almost unlimited.
See also miso; natto; soy sauce; tempe.
Alan Davidson was a distinguished author and publisher, and one of the world's best-known writers on fish and fish cookery. In 1975 he retired early from the diplomatic service—after serving in, among other places, Washington, Egypt, Tunisia, and Laos, where he was British Ambassador—to pursue a fruitful second career as a food historian and food writer extraordinaire. Among his popular books are Seafood of South-East Asia, North Atlantic Seafood, and Mediterranean Seafood. In 2003, shortly before his death, he was awarded the Erasmus Prize for his contribution to European culture.
Shurtleff, William, and Aoyagi, Akiko (1983), The Book of Tofu, Berkeley, Calif.: Ten Speed Press.
