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All About Tofu

Tofu—from silken to firm and more—is an essential ingredient in East and Southeast Asian cuisine. Follow along to learn more about this versatile food.
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Published Sept. 25, 2023.

Like bread or cheese, tofu is a staple food that requires just a few ingredients. But from that basic starting point, you can make many delicious, distinct versions. For tofu, the most important component is typically soybeans. The United States produces more than 4 billion bushels of soybeans per year, but a significant majority is used as animal feed, with only a small portion produced for human consumption as edamame; tempeh; soy milk; and of course, tofu. Its clean, vegetal flavor is all-important in a vast array of cuisines around East and Southeast Asia. From velvety silken blocks to delightfully airy puffs and chewy tofu skin, it comes in a wide range of styles that can be pan-fried, deep-fried, chilled, marinated, braised, stuffed, simmered in soups, and more.

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The History of Tofu

It is unclear when and by whom tofu was invented, but it likely originated in China thousands of years ago, as soybeans are native to China and are considered to be one of the five sacred grains, writes Andrea Nguyen in Asian Tofu (2012). From China, it made its way to Japan in the eighth century and became an important ingredient across East and Southeast Asia. The word “tofu” is Japanese, from the Mandarin word “dòufǔ. It’s also known as “dubu” in Korean and “dau hu” in Vietnamese, and frequently appears on Chinese restaurant menus as “bean curd.”

Top left: Soaked soybeans ready to be ground into soy milk at Phoenix Bean in Chicago. Top right: Finished tofu being packaged in water in plastic containers. Bottom: Block tofu being cut before packaging. (Photos courtesy of Phoenix Bean)

Making Soy Milk for Tofu

Although tofu can be made from other beans and legumes, the first step of most tofu production is making soy milk. Unlike store-bought soy milk sold in cartons, this soy milk is not watered down to a thinner, more drinkable consistency and does not contain sweeteners, gums, or stabilizers; it’s rich and thick and tastes deeply of soybeans. The beans are soaked for at least six hours and are then ground with water. The soy milk is strained to remove the fibrous pulp, which is often used as animal feed or fertilizer. In Japanese cuisine, these solids, called okara, can be eaten in a salad, said Tokiko Sawada, co-owner of Binchoyaki, a Japanese restaurant in Sacramento, California.

Unlike medium, firm, and extra-firm tofu, silken tofu isn't stirred before setting, so it's extra smooth and doesn't have any large curds.

The Different Types of Tofu

Soybeans can be made into a wide range of foods, and even within the tofu category there are dozens of different styles and products. For this story, we focused on unflavored block tofus in a variety of firmnesses. We also included three kinds of prepared tofu: fried tofu, tofu puffs, and tofu skin (or yuba). We spoke to tofu makers and experts in East Asian and Southeast Asian cuisines to learn about how tofu is made and used.

Silken Tofu

How Is Silken Tofu Made and Packaged? 

Silken tofu is the softest, most delicate form of block tofu. All block tofu is made by heating soy milk and adding a coagulant. But then, to achieve the desired characteristics of each type, the process begins to diverge. For silken tofu, the mixture is poured into a mold—often the container it’s sold in—before it coagulates. The tofu isn’t stirred before it sets, giving it a perfectly smooth, silky texture. 

How Is Silken Tofu Used?

Silken tofu is quite delicate, so it’s often reserved for cold applications such as Japanese hiyayakko, silken tofu with toppings such as bonito flakes, ginger, and green onion and soy sauce. We also use it in the Spicy Cold Tofu from A Very Chinese Cookbook (2023), topped with a dressing of chiles, soy sauce, rice vinegar, sugar, ginger, garlic, and a sprinkling of herbs. It can be added directly to soups and stews, such as in Korean kimchi sundubu jjigae, a spicy tofu stew. Silken tofu shouldn’t be pressed before using in order to avoid disturbing the delicate, custardy texture. 

A spicy dressing is the perfect match for cold, custardy silken tofu.

Shopping Tips for Silken Tofu

All silken tofu is fairly soft and delicate. However, you may see packages labeled with different levels of firmness, which manufacturers achieve by adjusting the amount of coagulant. Those labeled “soft” tend to have a more pudding-like texture, while “firm” are more sliceable. We purchased five brands of silken tofu, some regional and some nationally available, choosing the “soft” option if multiple firmnesses were available. 

One product, made by Morinaga Mori-Nu, was packaged in an aseptic cardboard box. With this packaging system patented by Morinaga, each package is filled and sealed while the liquid soy milk and coagulant are hot, so when the tofu cools and sets, it is already packed and shelf-stable, explained our science editor, Paul Adams. Although it is often sold refrigerated, unopened packages can be stored at room temperature for long periods of time. Tasters noticed some bitterness and sourness in this boxed tofu. It was also so delicate that it was difficult to remove from the box intact.

Overall, we preferred the silken tofus sold in plastic tubs as they were smooth but not overly fragile. The ingredients for these tofus are heated before packaging, and therefore the products must be refrigerated. Only one, the silken tofu from Nasoya, was so fragile that we couldn’t get it out of the plastic tub without it falling apart. Tasters were fans of San Sui silken tofu, remarking on its “creamy” flavor and “very, very smooth texture.” 

Many Korean markets also sell soon tofu, which is silken tofu sold in tube form and commonly used for sundubu jjigae, explained Sarah Ahn, the blogger behind Ahnest Kitchen. (Ahn is also the Cook’s Illustrated social media coordinator.)

Soft, Medium, Firm, and Extra-Firm Tofu

How Are Soft, Medium, Firm, and Extra-Firm Tofu Made?

Like silken tofu, other styles of block tofu are made by mixing hot soy milk with a coagulant. This coagulant could be magnesium chloride (also called nigari or bittern), calcium sulfate (gypsum), magnesium sulfate (epsom salt), glucono-delta-lactone, or a combination of these. Because the coagulants are heat-activated, the soy milk must be within a specific temperature range, 160 to 170 degrees Fahrenheit, to coagulate properly. The mixture curdles and the curds are agitated either by hand or by machine, depending on the scale of the operation. It’s poured into trays, often lined with cheesecloth, and pressed to extract water and form a block shape. 

To make different firmnesses, producers can change the coagulation temperature, the concentration of soybean solids in the soymilk, the quantity of coagulant, and the amount of pressure when pressing. “How you break up the curds, what coagulant you use, how long you press it,” are also important variables, said Jenny Dao, operations manager of Chang Shing Tofu in Cambridge, Massachusetts. 

How Are Soft, Medium, Firm, and Extra-Firm Tofu Used?

Soft tofu can be used similarly to silken tofu, eaten in cold salads or gently added to soups and stews, such as mapo tofu from China’s Sichuan province (which is sometimes made with silken tofu) and West Lake Beef Soup (Xīhú Níuròu Gēng 西湖牛肉羹), which is named for the lake in Hangzhou, China.

Mapo tofu recipes call for either silken or soft tofu.

Medium to firm tofus vary in texture but are sometimes used interchangeably; it depends on personal preference. Tofus within this firmness range are ideal for stir-frying, pan frying, and deep frying due to their sturdier texture and lower moisture content. In the banchan (Korean side dish) dubu jorim, firm tofu is pan-fried and braised in a spicy sauce. It is frequently stir-fried or pan-fried in Chinese cuisine as well, such as in tofu with black bean sauce. In the Chinese dish pipa tofu, medium to firm tofu is mashed with ground shrimp and deep-fried. In the Japanese dish agedashi, medium to firm tofu (although sometimes soft or silken) is battered, deep-fried, and served in a dashi-based sauce. If you’re pan-frying or deep-frying tofu, it will be drier, firmer, and crisper if you first remove excess moisture. Grace Young, author of The Breath of a Wok (2004), recommends draining the tofu and setting it on a towel, seasoning it with salt to draw out moisture, and weighing it down with a heavy object. Some people instead use special tofu presses to remove water from tofu. 

Extra-firm tofu (left) has a sturdier, more dense texture than soft tofu (right). Both can be pressed to remove moisture and soft tofu will expel more water. 

Medium to extra-firm tofus are sometimes eaten cold, such as in Vietnamese summer rolls paired with shrimp or pork. They are also used in soups and stews, such as Chinese hot and sour soup, where it’s desired that the tofu retains its shape and texture. Tofu is sometimes used in Thai cuisine in stir-fries, soups, stews, and braises, but it’s a “recent addition to Thai cuisine, originally through Chinese immigrants,” said Thai food blogger Leela Punyaratabandhu. “Even though tofu wasn’t part of Thai cooking before, it has now become important.” 

The firmer the tofu, the higher the amount of protein per serving.

Shopping Tips for Soft, Medium, Firm, and Extra-Firm Tofu

We compared five soft tofus and five firm tofus from both regional and nationally available brands. Overall, we found that a higher protein content as listed on the nutrition label often correlates with a firmer texture because there is less water and more soybean. Our tasters especially liked the firm tofu from nationally available House Foods, which had “vegetal soy flavor” and “pleasantly beany flavor.” The firm tofu from Pulmuone was “vegetal” and “extra beany,” but some tasters noticed a subtle “sour” or “tannic” flavor. Tasters enjoyed the soft tofu from the same brand, with its “soft and luxurious” texture and “clean, milky” flavor. Large producers distribute tofu nationwide, but smaller brands are typically sold regionally. In some areas, you might be able to find fresh tofu being made daily, such as at New York Chinatown’s Fong On. Freshly made tofu, said Young, is “more delicate,” and “you get that sweet essence of soybean.”

Fried Tofu and Tofu Puffs

What Are Fried Tofu and Tofu Puffs and How Are They Made?

Fried tofu is simply packaged deep-fried tofu. At Phoenix Bean in Chicago, they use extra-firm tofu, cut it into triangles, and fry it in vegetable oil, said owner Jenny Yang. 

Tofu puffs are more labor-intensive to make. Instead of starting with already-made tofu, airy curds are created by adding coagulant to soy milk and then gushing cold water into the hot soy milk from a certain height to create enough pressure to “break the curds into clouds,” Yang described. Then, the tofu is pressed and refrigerated overnight to remove water before being fried. When fried properly (starting at a low temperature and raised to a high heat), the tofu puffs are almost hollow and irregularly spongy on the inside. 

How Are Fried Tofu and Tofu Puffs Used?

Fried tofu is a common ingredient in some Thai dishes, especially stews. In Hot Thai Kitchen (2016), Pailin Chongchitnant uses it in her Five-Spice Vegetable Stew (Palo Jap Chai), adding it to the pot toward the end of cooking. It can also be added to hot pot or used in stir-fries.

Tofu puffs are used in bún riêu, a Vietnamese soup made with a pork and tomatobased broth, crabmeat, and more pork and served with noodles, vegetables, bean sprouts, and cabbage. When used in soups, “they soak up all that broth. It’ll be a big, delicious cotton ball of soup,” said chef Tu David Phu. Tofu puffs are also used in Buddha’s delight, or lo han jai, a popular Lunar New Year dish with noodles, cabbage, tofu skin, and mushrooms. 

Shopping Tips for Fried Tofu and Tofu Puffs

Look for fried tofu and tofu puffs in the refrigerated tofu section or the freezer section of Asian supermarkets.

Tofu Skin/Yuba

What Is Tofu Skin/Yuba and How Is It Made?

Similar to dairy milk, soy milk forms a skin when heated. “As water evaporates from the surface...” said Adams, “the protein left behind knits together—no need for coagulant—into a toothsome, flavorful sheet.” It can be sold fresh or dried. 

How Is Tofu Skin/Yuba Used?

Fresh tofu skin, also called yuba, can be used in various steamed dishes, such as stuffing it with “mushrooms, bamboo shoots, a little celery and rolling it,” said Young. It is used, along with sliced meats, mushrooms, leafy greens, and garlic chives, in the version of crossing the bridge noodles—a rice noodle soup from China’s Yunnan province—featured in The Woks of Life (2022) cookbook.

Packaged dried tofu skin, sometimes called bean curd sticks, is hard and needs to be soaked before use. Along with tofu puffs, it’s a common ingredient in the Lunar New Year dish lo han jai. In restaurants, tofu skin is often used as a vegetarian replacement for meat in dishes such as sandwiches or tacos. 

Shopping Tips for Tofu Skin/Yuba

Look for tofu skin/yuba at Asian supermarkets. You can find fresh versions in the refrigerated tofu section and shelf-stable dried tofu skin elsewhere in the stores.

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