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Tofu-beijingchinajpg
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Seasoned tofu cubes in a Chinese dish
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bean curd
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Burmese
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(pebya/péprā:)</br>''or'' (tofu/tiuphü:)
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Khmer
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តៅហ៊ូ
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豆腐 or 荳腐 showflag=p
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dòufǔ
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tou-fu
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dauh-fuh
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dau<sup>6</sup>-fu<sup>6</sup>
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tāu-hū
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tokwa
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Indonesian
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tahu
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豆腐
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とうふ
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tōfu
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tôhu
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豆腐
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두부
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dubu
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tubu
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tauhu
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tahu
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(the Japanese
Soy Milk , and then pressing the resulting curds into blocks. The making of tofu from soy milk is similar to the technique of making
Cheese from
Milk (
Fermentation ).
Wheat Gluten , or seitan, in its steamed and fried forms, is often mistakenly called "tofu" in Asian or vegetarian dishes.
Tofu is made by coagulating soy milk and pressing the resulting curds. Although pre-made soy milk may be used, most tofu producers begin by making their own soy milk, which is produced by soaking, grinding, boiling, and straining dried (or, less commonly, fresh)
Soybeans .
Coagulation of the protein and oil (
Emulsion ) suspended in the boiled soy milk is the most important step in the production of tofu. This process is accomplished with the aid of coagulants. Two types of coagulants (salts and acids) are used commercially. Berk, Zeki. (1992).
"Tofu" . Chapter 9.5. ''Technology of Production of Edible Flours and Protein Products from Soybeans.''. FAO Agricultural Services Bulletin No.97. ISBN 92-5-103118-5 The third type of coagulant, enzymes, is not yet used commercially but shows potential for producing both firm and "silken" tofu.
- '''. As such, many tofu manufacturers choose to use this coagulant to be able to market their tofu as a good source of calcium.
- Chloride-type Nigari salts - is only very slightly soluble in water and acts differently in soy protein precipitation, the basis for tofu formation. These are the coagulants used to make Japanese-style tofu with a smooth and tender texture. In Japan, a white powder called '' Nigari '', which consists primarily of magnesium chloride, is produced from Seawater after the Sodium Chloride is removed and the water evaporated. Depending on its production method, ''nigari'' may also contain small quantities of Magnesium Sulfate (Epsom salt), Potassium Chloride , Calcium Chloride , and trace amounts of other naturally occurring salts. Although the term ''nigari'' is derived from ''nigai'', the Japanese word for "bitter," neither ''nigari'' nor pure magnesium chloride imparts a perceivable taste to the finished tofu. Calcium chloride is a common coagulant for tofu in North America. Liu, KeShun. (1997). '' ''Soybeans: Chemistry, Technology, and Utilization ''
- (GDL): A naturally occurring organic acid also used in cheese making, which produces a very fine textured tofu that is almost jelly-like. This coagulant is used especially for "silken" and softer tofus, and confers an almost imperceptible sour taste to the finished product. Guo S.-T. and Ono T. (2005). The Role of Composition and Content of Protein Particles in Soymilk on Tofu Curding Glucono-d-lactone or Calcium Sulfate. ''Journal of Food Science'' 70 (4): 258–262. Commonly used together with calcium sulfate to give soft tofu a smooth tender texture.
- Among Enzymes that have been shown to produce tofu are Papain , and alkaline and neutral Proteinases from microorganisms. In the case of papain, the enzyme to substrate ratio, by weight, was held constant at 1:400. An aliquot of 1% crude papain was added to "uncooked" soy milk at room temperature and heated to 90–100 degrees Celsius. Liu, KeShun. (1997). '' ''Soybeans: Chemistry, Technology, and Utilization ''
Contemporary tofu manufacturers may choose to use one or more of these coagulants, since they each play a role in producing a desired texture in the finished tofu. Different textures result from different pore sizes and other microscopic features in tofus produced using each coagulant. The coagulant mixture is dissolved into water, and the solution is then stirred into boiled soy milk until the mixture curdles into a soft
Gel .
The curds are processed differently depending on the form of tofu that is being manufactured. For soft silken tofu (; ''nèn dòufǔ'') or tofu flower (, ''dòuhuā'') the soy milk is curdled directly in the tofu's selling package. For standard firm Asian tofu, the soy curd is cut and strained of excess liquid using
Cheese Cloth or
Muslin and then lightly pressed to produce a soft cake. Firmer tofus, such as Asian dry tofu () or Western types of tofu, are further pressed to remove even more liquid. In Viet Nam, the curd is strained and molded in a square mold and the end product is called
''đậu khuôn'' (molded bean) or ''đậu phụ'' (one of the Vietnamese ways to pronounce the Chinese doufu). The tofu curds are allowed to cool and become firm. The finished tofu can then be cut into pieces, flavoured or further processed.
Although tartness is sometimes desired in dessert tofu, the acid used in flavouring is usually not the primary coagulant since it is not desirable to the flavour or texture of the resulting tofu to add it in a sufficiently high concentration so as to induce coagulation. A sour taste in tofu and a slight cloudiness in its storing liquid is also usually an indication of bacterial growth and, hence, spoilage.
There is a wide variety of tofu available in both Western and Eastern markets. Despite the daunting variety, tofu products can be split into two main categories: ''fresh tofu'', which is produced directly from
Soy Milk , and ''processed tofu'', which is produced from fresh tofu. Tofu production also creates important side products which are often used in various cuisines.
Depending on the amount of water that is extracted from the tofu curds, fresh tofu can be divided into three main varieties.
- ( or , ''nèn dòufǔ'' or ''huá dòufǔ'', in '' (, ''dòu huā'' or , ''dòufǔ huā'' in Chinese), or ''tofu brain'' ( or , ''dòufǔ naǒ'' in Chinese), often eaten as a dessert, but sometimes with salty pickles or hot sauce added instead, is another type of soft tofu with an even higher moisture content. Because it is nearly impossible to pick up this type of tofu with Chopsticks , it is generally eaten with a spoon. ''Edamame tofu'' is a Japanese variety of ''kinugoshi tōfu'' made from ''edamame'' (fresh green soybeans); it is pale green in color and often studded with whole ''edamame''.
- (simply called ''dòufǔ '' in Chinese; , ''momendōfu'' in .Shurtleff, William and Aoyagi, Akiko. (2004). History of Tofu . ''A Special Report on The History of Traditional Non-Fermented Soyfoods'' (unpublished manuscript) Soyinfo Center website
- (, ''dòu gān'' in Chinese, lit. "dry tofu"): An extra firm variety of tofu with the least amount of moisture of all fresh tofus. It has the firmness of fully cooked meat and a somewhat rubbery feel similar to Paneer . When sliced thinly, this tofu can be crumbled easily. The skin of this form of tofu has the pattern of the muslin used to drain and press it. Western firm tofu is milled and reformed after the pressing and sometimes lacks the skin with its cloth patterning. One variety of dried tofu is pressed especially flat and sliced into long strings with a cross section smaller than 2 mm × 2 mm. Shredded dried tofu (, ''dòu gān sī'' in Chinese, or simply , ''gān sī''), which looks like loose cooked Noodle s, and can be served cold, stir-fried, or similar in style to Japanese '' Aburaage ''. photo
Fresh tofu is usually sold completely immersed in water to maintain its moisture content. and . (2004). :. ''''. ISBN 4-10-471901-3
Many forms of processed tofus exist, due to the varied ways in which fresh tofu can be used. Some of these techniques likely originate from the need to preserve tofu before the days of refrigeration, or to increase its shelf life and longevity. Other production techniques are employed to create tofus with unique textures and flavours.Shurtleff, William and Aoyagi, Akiko. (2004).
History of Fermented Tofu ''A Special Report on The History of Traditional Fermented Soyfoods'' (unpublished manuscript)
Soyinfo Center website
- ''' (cultivated with '' Monascus Purpureus '') is added for color.The Hwang Ryh Shang Company of Taiwan, a major producer of pickled tofu, mislabels this ingredient as "red date" ( Jujube ) on the English-language list of ingredients on its product labels Yifanmall , although the Chinese list of ingredients on the same product lists 紅糟 (red yeast rice).
- ''', sweet sauce, and/or hot sauce.
but rather from
Gelatin or
Agar ose]]
Flavours can be mixed directly into curdling soy milk while the tofu is being produced.
- : Common sweet dessert tofus include peanut tofu (, luòhuāshēng dòufǔ in Chinese and ''jimami-dōfu'' in Japanese), almond tofu (, xìngrén dòufǔ in Chinese; , annindōfu in Japanese), mango tofu, and coconut tofu. In order to produce these forms of tofu, sugar, fruit acids, and flavourants are mixed into soy milk prior to curdling. Most sweet tofus have the texture of silken tofu and are served cold.
- --- Products called "almond tofu" in some cases are actually not made from tofu but are instead gelatinous desserts made from Agar or Gelatin and whitened with Milk or Coconut Milk . In Japan these are canned with syrup and sold as a sweet dessert.
- : Egg tofu (; dàn dòufǔ, in Chinese) (; yùzǐ dòufǔ; lit. "jade tofu," in Chinese; ; tamagodōfu, in Japanese) is the main type of savoury flavoured tofu. Whole beaten eggs are filtered and incorporated into the soy milk before the coagulant is added. The mixture is filled into tube shaped plastic bags and allowed to curdle. The tofu is then cooked in its packaging and sold. Egg tofu has a pale golden color that can be attributed to the addition of egg and, occasionally, food coloring. This tofu has a fuller texture and flavour than silken tofu, which can be attributed to the presence of egg fat and protein.
- With the exception of the softest tofus, all forms of tofu can be fried. Thin and soft varieties of tofu are in Chinese, ''dòupào'', lit. "bean bubble," describing the shape of the fried tofu as a bubble).
- Tofus such as firm Asian and dry tofu, with their lower moisture content, are cut into bite-sized cubes or triangles and deep fried until they develop a golden-brown, crispy surface ( in Chinese, ''zhà dòufǔ'', lit. "fried tofu"). These may be eaten by themselves or with a light sauce, or further cooked in liquids; they are also added to hot pot dishes or included as part of the vegetarian dish called '' Luohan Zhai ''.
- ( in Chinese, lit. "thousand layer tofu" or "frozen tofu"): By freezing tofu, the large ice crystals that develop within the tofu results in the formation of large cavities that appear to be layered (pseudostratified). The frozen tofu takes on a yellowish hue in the freezing process. Thousand layer tofu is commonly made at home from Asian soft tofu though it is also commercially sold as a regional specialty in parts of Taiwan. This tofu is defrosted and sometimes squeezed of moisture prior to use.
- '''Japanese , a center of Japanese Buddhism famed for its '' Shōjin Ryōri '', or traditional Buddhist Vegetarian Cuisine . It is excellent for camping, in that it is very light, may be sold flattened, and makes a very filling nutritious meal on the road. Like many freeze-dried foods, it is soaked in hot water or broth before eating, taking on a spongy texture when reconstituted. Freeze-dried tofu is also found in instant soups (such as Miso Soup ), in which the toppings are freeze-dried and stored in sealed pouches.
Tofu production creates some edible byproducts. Food products are made from the protein-oil film, or "skin," which forms over the surface of boiling soy milk in an open shallow pan. The leftover solids from pressing soy milk is called ''okara''.
Boiling of soy milk, in an open shallow pan , produces a film or skin composed primarily of a soy protein-lipid complex on the liquid surface. The films are collected and dried into yellowish sheets known as or '''soy milk skin''' (, ''fǔ pí'' in Chinese; , ''yuba'' in Japanese). Its approximate composition is : 50–55% protein, 24–26% lipids (fat), 12% carbohydrate, 3% ash, and 9% moisture.
The soy daily
The yuba can also be bunched up to stick form and dried into something known as "tofu bamboo" (, ''fǔ zhú'' in Chinese; ''phù chúc'' in Vietnamese; ''kusatake'', Japanese), or a myriad of other forms. Since tofu skin has a soft yet rubbery texture, it is folded or shaped into different forms and cooked further to imitate meat in vegetarian cuisine.
Some factories dedicate production to tofu skin and other soy membrane products.
Okara (, ''xuě huā caì'', lit. "snowflake vegetable"; , ''dòufǔ zhā'', lit. "tofu sediment/residue"; ''kongbiji'', 콩비지 in Korean), sometimes known in the west as soy pulp, is the fibre, protein, and starch left over when soy milk has been extracted from ground soaked soybeans. Although it is mainly used as animal feed in most tofu producing cultures, it is sometimes used in Japanese and Korean cuisines. It is also an ingredient for
Vegetarian Burgers produced in many western nations. Okara is rarely seen or used in Chinese cuisine.
- (): A type of tofu made from plain black beans and soybeans, which is usually made into ''dòuhuā'' () rather than firm or dry tofu. The texture of black bean tofu is slightly more gelatinous than regular tofu flower and the color is greyish in tone. This type of tofu is eaten for the earthy "black bean taste."
- ''''' ( ''chana Dal '') flour instead of soybeans; the Shan variety uses Yellow Split Pea flour instead. Both types are yellow in color and generally found only in Myanmar , though the Burman variety is also available in some overseas restaurants serving Burmese Cuisine . Burmese tofu recipe
:Rice tofu, called ''hsan to hpu'' (or ''hsan ta hpo'' in Shan regions) is made from rice flour (called ''hsan hmont'' or ''mont hmont'') and is white in color, with the same consistency as yellow Burmese tofu when set. It is eaten as a salad in the same manner as yellow tofu.
