[Tofu (Japan, US); Dofu, Doufou (China); Tubu (Korea); Toad Food (improper), Bean Crud (improper)]
Basically, bean curd is cottage cheese made by coagulating ground up strained and cooked soybeans (soy milk) rather than dairy milk. First appearing during the Chou Dynasty (1132-246 BCE), there are several theories for its origin, all of which are unadulterated speculation.
The photo specimens are, from left to right, silken, soft and firm tofu, all by the same manufacturer in Los Angeles.
If you want to know how to make all forms of tofu and every detail about
it, I recommend The Book of Tofu by William Shurtleff & Akiko
Aoyagi - Autumn Press 1975.
In the US tofu has become a focus for laughter due to vegetarians over-using it and trying to build turkeys out of it for Thanksgiving dinner - as well as tofu sausages, hot dogs, hamburgers and jerky. Now I'm not anti-vegetarian, and was a vegetarian for almost the regulation 9 years (though never an "ethical" vegetarian), but I think building vegetarian imitations of dead animal parts is a little funny, despite it's long history in Asia. I use various forms of bean curd fairly regularly, but just can't resist calling it "bean crud".
In most of Asia tofu is used in moderation as a flavor absorbing and textural ingredient in many interesting dishes, but only occasionally as a main ingredient and then usually as an appetizer or desert. Consumption is heavier in parts of southern China, but rice is still the main staple and tofu an accessory. This is as it should be, as there are still open questions regarding health impacts from heavy tofu consumption - see Soybeans and Health for details.
Because of the many uses to which tofu is put, there are a number of ways to make it resulting in different textures. This may be controlled by choice of coagulant, by draining and/or pressing.
When I first bought tubs of tofu many years ago it needed to be used in just a few days or it would go sour. Sterile packaging has been improved to the point some brands don't expire for 3 months and probably last longer.
Tofu tubs should be kept refrigerated at all times. Once opened tofu should be used up in just a couple of days. It is recommended that opened tofu be kept refrigerated submerged in clean water that's changed every day. If tofu smells or tastes at all sour it has turned and should be discarded. If it's very faintly sour it may be refreshed by cutting into large cubes and par boiling them in lightly salted water for about 3 minutes.
Some of the tofu made here in Los Angeles, particularly for the Vietnamese community, is not cut into cubes nor packaged in tubs. It is shaped kind of like a large dinner roll and wrapped in plastic wrap. This tofu must be delivered fresh daily and used the same day. It would still be good for deep frying the next morning if properly refrigerated.
A convenient way to press a small amount of tofu is to prepare the tray as for draining except remove the top film entirely. Set a full tub of tofu n top (or an empty tub filled with something heavy). Refrigerate - the longer it sits the firmer it gets. For larger amounts, and for deep frying which wants a hard pressing, a rig like that pictured is needed. Set a board on a shallow slant, cover it with a dish towel, slice the tofu to size and arrange the slices on the board. Cover with another board and put several pounds of weights on top of it. Retired cutting boards are excellent for this purpose. Press a few hours for deep fried tofu, less for other uses.
Silken Tofu is never pressed - that would destroy its texture.
Thick Agé![]() The outside is crisp and light brown while the inside is white and spongy. You can eat them as-is, but they are commonly subjected to further cooking of some sort. While generally put to other uses, these agé can be stuffed, if the puffy kind aren't commercially available and the hassle of making them at home is not practical. You do need to scoop some of the white inside out before stuffing. The photo shows both the traditional triangular form and the
rectangular form more common today. The rectangular pieces were
3.75 x 2.13 x 0.80 and weighed 2-5/8 ounces. In other words, a 19
ounce block has shrunk to less than 8 ounces - but gained considerable
calories due to oil. The photo specimens were fried quite long and
have a fairly thick crust - shorter frying may be desirable for some
applications.
Details and Cooking.
Deep Fried Soybean Cake![]() Here in Los Angeles, the many Asian markets carry deep fried
tofu of this type in many shapes and sizes, packed on foam trays or
in plastic bags. They are soft on the outside, never crispy, and
foamy on the inside. They have many uses in stir fries and stews.
The photo specimens were cubes about 1-1/2 inches on a side -
purchased from a large Asian market in Los Angeles (San Gabriel) for
2020 US $2.39 for an 8 ounce package. Ingr: Soy Bean, Soy Bean Oil,
Water, Calcium Sulphate.
Ganmo![]() This is the prototype veggie burger - no attempt to make it
taste like beef at this point though. Ganmo are made in the form of patties,
similar to hamburger patties, or balls, similar to meatballs. They are
made of tofu and grated or slivered vegetables, then deep fried in oil
(some people simmer them in a dashi stock instead). I prefer patties to
balls as the balls remain kind of mushy inside. Commercial products are
generally firmer but much heavier than home made.
Details and Cooking.
Agé Pouches & Puffs![]() |
This is a form much used in China, but not Japan and I haven't seen any of it in the Korean markets either. The firmest type of tofu is made and spread onto cloths. For the thinnest versions a stack of as many as 100 cloths is made. The stack is subjected to very heavy pressure in a screw press or similar device. This comes in many forms and only some of the most important are shown here.
Pressed Tofu Blocks![]()
These blocks of very firm tofu (about as firm as Monterey Jack) are
available in plain (right) and "baked" (left). The baked variety is
coated with various flavorings. The photo specimens were coated with
soy sauce, sesame oil, chili, aniseed and salt The "standard" size is
roughly 2.7 x 2.2 inches and 0.6 inch thick, sold in packages of
4 squares, weighing 6.7 ounces. Other sizes are also found. The plain
photo specimens were 5.1 x 2.7 x 0.7 inches, two to a package
weighing 6-1/4 ounces. This form can be sliced and diced and
used as an ingredient in stir fries, stews, sauces and even salads.
It can stand up to extended cooking. Purchased for 2016 US $2.49 per
6.7 ounces.
Pressed Tofu Sheet![]() For another brand purchased at the same market (also from China and shipped frozen) the sheets were 18-1/2 x 9 inches and only 0.015 inch thick. Ingredients: Soybean, Water. This stuff feels like fabric and stands up very well to handling -
and takes about 15 minutes of simmering to be tender.
Pressed Tofu Noodles![]()
These are sold fresh (as shown) and dried (usually straight). The fresh
may be seasoned before packaging and will then be light brown in color.
The individual noodles in the photo were about 0.10 inches square
(slightly variable) but they are often a bit wider and more erratic
in size (11).
Pressed Tofu Knots![]()
These, both by the same company in Los Angeles, were labeled
"Taiwan Soy Sheet Knot" (left) and "Shanghai Soy Sheet Knot" (right)
The Taiwan were tied from a strip 7-3/4 x 2 x 0.05 inches and weighted
1/2 oz each. The Shanghai were tied from a strip 8 x 3-1/2 x 0.015
inches and weighed 1/3 ounce each. Cooking suggestions were,
"Pan fried, stir fried with vegetable, hot pot, marinated"
(11).
|
Expensive in Japan but reasonably cheap in China, this product is sheets of the skin that forms on top of the cooking pots when making tofu - though some shops make only the skins and skip the tofu. The skin is cut at the edges of the pot and a stick is run under the center. The stick is raised leaving the skin draped down on both sides. It is now ready for drying or whatever other preparation will be used.
Bean Curd Skin - Flat Dried![]() Found in Chinese markets but also commonly used in Japan this form is
less common than others due to the obvious logistic problems in
transport and storage. These sheets are extremely thin and brittle -
they'll crumble if you look at them wrong. The photo specimen was 21
inches long (unfolded) 7-1/2 inches wide and 0.010 (one 100th) inch
thick. With a 5 minute soak it becomes rubbery and slightly elastic,
suitable for wrappings and similar uses. Flavor is, as with most tofu
products, fairly bland, but it will absorb flavors from other
ingredients.
Bean Curd Skin Sticks![]() These bunched up sticks of tofu skin have been the most common
form found in Chinese markets but seems to be being overtaken by the
flat sheets. It's more durable than sheet, but not a whole lot.
Sticks are usually broken up and given a long soak before adding to a
recipe. Some spots will be too thick to soak soft and must be picked
out and discarded. The photo specimens were 10-1/2 inches long and
weighed 3/4 ounce each. Thickness of the leaves was about 0.015 inch.
Fresh Tofu Skin Pouches![]()
These aren't really pouches as they are just a folded flat
roll and the material is too fragile to unroll. They can be used
sliced. The photo specimens were 4-1/2 inches long (twice that
unfolded), 3-1/2 inches wide and weighed 2-1/2 ounces each. The
leaves they were rolled from were 0.010 (one 100th) inch thick.
Cooking suggestions were, "Pan fried, stir fried with vegetable,
hot pot, marinated" (11). I have recently
purchased these from a tub at a large Asian market in Los Angeles
(San Gabriel) for 2020 US $0.68 / pound. They were about 3 x 3 x 0.65
inches and wighed about 3.3 ounces each. The layers were about 0.03
inch thick.
|
This form is often served as an appetizer but can be used wherever
its porous nature would be good for holding sauces or dips. When tofu is
frozen the water forms large crystals which leave a lot of holes when they
melt and drain out. It leaves the tofu fairly firm and with a slightly
yellow color. The "thousand layer" name comes because the crystals follow
the texture which in pressed tofu gives a layered look where there are
actually no layers.
This form is generally made at home from regular soft tofu. The
relatively slow freezing in a home freezing compartment encourages
large ice crystals thus desirably large holes. It is thawed and drained
(and sometimes squeezed) before using.
Photo by J Samuel Burner distributed under
Creative Commons
Attribution 2.0 license.
This is pretty much a Japan-only specialty. Some time between 1550 and
1650 Two traditional methods were developed, taking advantage of bitter
winter cold, but today this product is made in large industrial
facilities. First Frozen Tofu is made (se above), then the water is
wrung out and the Tofu is dried. This differs from the Vacuum Freze
Drying process, thus is correctly called Dried-Frozen Tofu. This tofu
is extremely light weight and will last for 6 to 8 months in a sealed
package kept in a cool environment away from sunlight. Absurdly expensive.
Details and Cooking.
This is sort of the tofu equivalent of aged soft cheese (think Roquefort or blue cheese) and is used throughout China and Southeast Asia as an ingredient and as a table condiment. Your average Asian market will have a slew of brands and varieties. If you like pungent dairy cheese you'll probably like this stuff too.
Blocks of tofu, usually about 1-1/2 inch in the longest dimension, are
fermented by a special process (traditionally under straw) and then
packed in liquid with flavoring ingredients.
Details and Cooking.
This is a form of very moldy fermented tofu, often of slightly purplish color, popular in China, particularly Sichuan and Hunan but also in Hong Kong, Taiwan and Indonesia. It is made by fermenting as long as several months in a brine made from salt, fermented milk, vegetables and meat, which may also include shrimp, amaranth greens, mustard greens, bamboo shoots and herbs.
The stench, which even enthusiasts admit smells like rotting garbage,
is noticeable for blocks around stalls and restaurants where it is cooked
and served (generally at night). It is most often pan or deep fried but
the photo specimen is in Sichuan Mala sauce.
Photo distributed under Creative Commons
Attribution-ShareAlike v3.0 Unported.
This page couldn't be complete without various attempts, both ancient and modern, to make tofu imitations of animal parts. The Chinese are very fond of creating exact replicas of whole animals out of tofu skin but these are mercifully not much available in the US.
Tofu Chicken- Shanghai Vegetarian![]() [Buddha's Chicken, Thit Ga Chay (Viet)]
This product is usually made by rolling up fresh tofu skins,
compressing in a cloth wrapping and steaming. The cloth is then
removed. This process makes the roll very firm with a somewhat
chicken-like texture. The texture is pleasing but making it taste
like chicken (or not) is up to the cook. The photo specimen was
5-1/4 inches long, 2-1/8 inches diameter and weighed 8-1/4 ounces.
Ingredients: soybean, water, salt. Cooking suggestions, "Pan fried,
stir fried with vegetable, hot pot, or soup for flavor"
(11).
Tofu Chicken- Oval Soy Patty, Vegan![]()
Not strictly tofu, except for tofu skin, but all soy, this "chicken"
is poured into a thin plastic mold, where it solidifies. Then it
is shrink packaged, mold and all, and frozen. The package says it can
be used in any recipe calling for chicken. It takes little cooking,
so is fine for stir fries, but can also take long cooking without
disintegrating. Texture is similar to undercooked chicken,
a little chewy. Taste is mild, remeniscent of chicken breast, but
with a somewhat beany undertaste. Ing: Water, textured
soybean isolate, textured soybean protein, soy beancurd skin,
soybeean oil, soy sauce, sea salt, sugar cane juice, spices
(mushroom extract, black pepper).
Tofu Duck- Buddha's Duck![]() Tofu Chitterlings![]() Tofurkey![]() Tofu Cold Cuts![]() Tofu Italian Sausage![]() Soy Dogs![]() |
Notes: