How to make yuba (soy milk skins)
Soy milk skins are widely used in Chinese and Japanese dishes, a delicious ingredient called yuba.
They can be eaten fresh and hot, like a tofu-flavored treat, or allowed to cool and used like a wonton wrapper to hold the ingredients for spring rolls or to wrap dim sum. If several skins are laid together and folded, they also can be steamed, baked or fried as a meat substitute.
It’s possible to make them at home, if time consuming, but it’s well worth the effort. When soy milk is heated to about 165 degrees, a skin made of linked proteins begins to form on its surface. Over the next 25 minutes, the skin thickens. It can then be removed for use in a variety of ways.
Asian cuisines have dozens and dozens of ways to use yuba. It tastes like tofu with a rich soybean aroma and a lightly chewy texture. Drop one into a bowl of pho, the Vietnamese soup made with clear chicken broth and vegetables. Fry it like bacon. Wrap it around any kind of filling.
To make yuba, use a double boiler or fashion a double boiler by setting a pot above another pot of simmering hot water. Pour about two inches soy milk into the top pot. As the soy milk heats to 165 degrees, a skin will start to form. After 25 minutes, the skin will be thick enough that it won’t fall apart.
Using a paring knife, slice around the edge of the skin so it comes free from the sides of the pot. Using your hands or, alternatively, two chopsticks, gently lift the skin off the milk. It can be eaten on the spot, or draped over a bamboo skewer laid across the top of a large bowl or pot to drip dry.
If you want to save some, place yuba between pieces of parchment paper and seal in a zip-closure bag. Use within a couple of days, as the yuba are perishable.
About 95 percent of the soybeans grown in the United States are genetically modified. If you want to avoid them, make sure the soy milk you buy is organic and has only two ingredients: water and soybeans. Some producers add a little sugar to sweeten the soy milk, which yields yuba that’s slightly sweet. It also is relatively easy to make soy milk yourself.
In a colander, rinse a pound and a half of organic soybeans in running water, then transfer them to a large pot. Cover them with cold water and let them sit on the counter overnight. The next morning discard the water, rinse the soybeans well and cover with fresh water. Work the beans with your hands to loosen their skins, and remove as many as you can. Using a blender and working in batches, blend beans with enough water to make a slurry. Place the batches of slurry in a stockpot until all the beans are processed. Add more water if needed to make the slurry thin and runny.
Place the pot on a burner over medium high heat, stirring frequently to prevent the slurry from sticking. As soon as the slurry boils, reduce the heat to medium low and cook for an additional 35-40 minutes, stirring occasionally to prevent sticking. Take the pot off the heat.
When the slurry has cooled enough to handle, line a pot’s bottom and sides with cheesecloth and pour the cooked slurry into it. Draw up the edges of the cheesecloth to make a bag, being careful to keep all the solids in the bag.
Squeeze out any retained soy milk in the bag so it drips back into the pot. If any solids have made it through the first straining, give it a second straining.
Jeff Cox is a Kenwood-based freelance food and garden writer.