Yu Ding Shing is one of few soy sauce makers that still does the entire process by hand.
Soy sauce is a versatile condiment. It can be used as a dip, a marinade, or poured directly over food. But making this simple condiment takes a lot of time and patience.
There are different varieties—dark, light, sweet, and salty—depending on the type of soybean used and how the beans are fermented. Most soy sauces are made with yellow soybeans, but in Taiwan, traditional makers like to use black beans and ferment them directly under the sun.
“Black soybeans are unique because they have high oil content, which gives the sauce a stronger aroma,” says Hsieh Yi-che, co-owner of Yu Ding Shing, a 60-year-old soy sauce brand in Taiwan. “The oil gives the sauce a smoother texture.”
A family-owned business, Yu Ding Shing has been making soy sauce for three generations. Hsieh follows a recipe that was passed down from his grandfather.
First, he steams the beans to soften them up. Then, he adds koji, a fermenting agent that’s also used to make sake and baijiu.
(Read more: Everything you’ve ever wanted to know about baijiu, China’s most potent liquor)
The mix is left to sit in a humidity-controlled room for a few days, during which mold develops on the beans. The mold breaks down the bean’s protein into amino acids, which contributes to soy sauce’s umami flavor.
Afterward, the mold is washed off. The beans are combined with different concentrations of salt and water, before they’re put in clay urns to ferment further. Taiwan’s hot and humid climate contributes to the fermentation process.
“The heat captured by the terracotta, that is really important to how it ferments,” explains Lisa Cheng Smith of Yun Hai Taiwanese Pantry, which sells Yu Ding Shing soy sauce to the U.S. market. “Some of their vats are three generations old. And because of the capillaries in the clay material, it just continues to absorb flavor and nuance.”
These decades-old vats make Yu Ding Shing’s soy sauce unique. “Each generation creates a different level of complexity and flavor,” Smith says.
After the sauce is done fermenting under the sun—the process can take anywhere from six months to a year—it’s taken out and cooked over a wood-fired stove twice.
During the second firing, the flavor is adjusted based on the desired result. Soy sauce used for dipping and braising tends to be better sweet, so sugar is added.
(Read more: How to make guabao, a Taiwanese braised pork belly sandwich)
For Hsieh, the process of making soy sauce is a labor of love, literally. On every vat, he and his brother place messages that read, “I love you,” in Chinese.
“It helps us pay more attention to them,” Hsieh says. “It gives us the responsibility to nurture them.
“I think the hardest part of making soy sauce is doing the same actions over and over again,” he adds. “Making soy sauce isn’t difficult, but doing the same thing over and over again is a test of patience,” one that this family has been doing, and hopes to continue to, for generations.
