What’s the Difference Between Regular Tofu and Silken Tofu? Ask Paul

Writing this biweekly column, I encounter endless misnomers, from “baby carrots” (not really immature) to “Red Delicious apples” (not truly delicious). But tofu’s common name “bean curd” is actually accurate: Tofu is curds made from soy beans.

First, soybeans are soaked and ground into a slurry. Insoluble solids get filtered out of the slurry, which is then diluted to the consistency of milk and cooked to improve digestibility, shelf life, and flavor. At this stage, it’s soy milk.

Next—very much like the process for cheese—a coagulant ingredient, typically a calcium or magnesium salt, is mixed into hot soy milk, which almost immediately causes dissolved proteins in the milk to aggregate together into curds. For most tofu, such as the familiar firm tofu sold in individual tubs of water, the curds are broken up, drained, and pressed to remove water. As it cools, the tofu gels into a firm block.

How firm a block? Tofu producers sell grades from extra-firm to extra-soft—the terms are relative—and the main difference among these is how much water is contained in the gel. Pressing tofu for longer, or with more pressure, will drain more water from it and create a firmer product. The final firmness can also be adjusted by changing the amount of dilution of the soy milk, the temperature of the coagulation, or the amount of coagulant salt that’s added, all of which change how closely the soy proteins mesh with each other and how much water they retain.

Silken tofu is a tofu made in a slightly different way, which gives it a delicate, smooth, and neatly sliceable pudding-like texture. This is the tofu you want in mapo tofu or in a vegan cheesecake. (It also comes in a variety of firmnesses, but even the firmest is spoonable.) It’s usually sold in aseptic cardboard packages. To make it, a smaller amount of coagulant ingredient is used, and the coagulant is often gluconic acid rather than a salt. The tofu forms its curd more slowly, and the curd is not disrupted or pressed, but left to its own delicate devices; indeed, it’s often coagulated directly in the same aseptic box it’s sold in.

Often known by its Japanese name, yuba, these thin yellowish sheets are very much like the skin that forms on pudding or hot cocoa. As water evaporates from the surface of simmering soy milk (as with dairy milk) the protein left behind knits together—no need for coagulant—into a toothsome, flavorful sheet. It’s then lifted off, optionally dried, and used for wrapping dim sum, stacked into chewy layers to approximate meat, or used in other delicacies.

In Burmese cooking, a savory tofu-like cake called “to hpu” is made from soaked and ground chickpeas and/or split peas. Unlike soy tofu, it’s not held together with coagulated protein but simply with the cooked starch from the legumes. It’s not dissimilar to Italian panelle.  

Want to know more? Visit a Manhattan tofu factory with Dan Souza!