Why It Works
- Using freshly grated ginger from a mature, plump root—rather than from a very young or older, shriveled one—ensures a substantial amount of zingibain, the enzyme that helps set the milk curd.
- Heating the milk to 170 to 175°F (77 to 79°C) guarantees it’s at the optimal temperature when mixed with the ginger juice, triggering the chemical reaction that sets the milk into a curd.
- Warming the ramekin with hot water and drying it just before use minimizes the temperature drop that occurs when the heated milk is poured in, further ensuring that the chemical reaction occurs.
When I was a kid, my family temporarily relocated to Hong Kong, where I became captivated by Cantonese cuisine. I developed a soft spot for tong sui, a category of lightly sweetened custards, porridges, and soups that literally translates to “sugar water.” Contrary to the name, most tong sui aren’t especially sweet. Many are rooted in traditional Chinese ideas of food as medicine, cooked to delight and soothe in equal measure. As a child, I was happy to interpret this as an opportunity to eat dessert and call it nourishment.
Ginger milk curd—a custardy, spoonable treat that sits texturally between pudding and soft tofu—became an instant favorite. In traditional Chinese medicine, ginger is believed to improve circulation and ease digestion, while its warming properties help balance the cooling nature of milk when the two are served together. I liked how the mildly spiced dessert coated my throat in gentle warmth, especially when it was chilly or I was under the weather.
After we moved back to the US, I tried making ginger milk curd, assuming it would be easy since it typically calls for just three ingredients: milk, ginger, and sugar. Several rounds of trial and error later, I realized the dish was surprisingly finicky, and its short ingredient list belies the complexity of the chemical reaction that makes it possible.
Serious Eats / Qi Ai
The Science Behind the Dessert
Ginger milk curd—or jiāng zhī zhuàng nǎi, literally “ginger juice colliding with milk”—is a wonder of culinary science. The dessert’s jiggly texture comes not from eggs, starch, or thickeners, as is typical of most Western-style puddings and curds, but from a chemical reaction that occurs when gently heated milk meets just-grated ginger juice. Done right, this “collision” awakens zingibain, a protease enzyme found in ginger. When combined with milk, zingibain alters the structure of the casein proteins, causing the liquid to gel into a silky, wobbly curd.
The Best Ginger to Use
The recipe starts with freshly grated ginger. It’s important to look for plump, mature ginger with smooth, taut skin. The ginger should feel heavy for its size, a sign of high moisture content, which makes it easier to juice. Older ginger that is woody or shriveled tends to be drier and more fibrous, yielding less juice. On the other end, very young ginger with pale yellow skin and pink tips is also not ideal, since its milder juice may not contain enough zingibain to set the curd properly. Once grated, the ginger should be used within 10 to 15 minutes, as zingibain activity declines rapidly. This is why pre-grated ginger pulp and pre-bottled ginger juice, while convenient, won’t work for this recipe.
Selecting Your Dairy
Buffalo milk has historically been the dairy of choice in this dish, thanks to its high protein and fat content, both of which encourage a richer, more firmly set curd. These days, many home cooks opt for cow’s milk instead, choosing the full-fat variety to maintain the curd’s signature silkiness. Cow’s milk has enough protein to set the curd beautifully, but if you prefer a thicker texture, you can whisk some whole milk powder into the cold milk before heating (2 teaspoons for the 1 1/2 cups of milk in this recipe is enough to encourage coagulation without becoming chalky). And if you can find buffalo milk in your area, feel free to use it instead of cow’s milk.
Serious Eats / Qi Ai
The Key Techniques for Successfully Setting Your Milk Curd
Get the Temperature of the Milk Right
The milk’s temperature is critical to the success of the curd, as only a narrow range will trigger the enzymatic reaction. Since the milk’s temperature drops slightly once it leaves the heated pot, you should bring the dairy to a temperature of 170 to 175°F (77 to 79°C), stirring occasionally to prevent hot or cold spots. In that range, the milk will be warm and steaming—hot enough to activate the zingibain enzyme but not so hot that it destroys it. The best time to stir in the sugar is after the milk has warmed but before removing the pot from the heat, when it will dissolve easily. I prefer a milder sweetness level here, but those who like a sweeter flavor can add up to five teaspoons for two servings.
How You Pour Matters
The final critical step is the pour. When adding the milk to the ginger juice, be sure to stream it in from a height of six to eight inches in one continuous motion. This isn’t for show: Pouring this way gently agitates the milk, evenly dispersing the enzyme throughout the liquid without needing to stir. A fragile protein network begins forming within seconds, and stirring at this point could interrupt that process. The gentle agitation also helps equalize the mixture’s temperature, minimizing the risk of hot or cold pockets that could prevent the curd from setting. Simply position the pot of milk six to eight inches above the ramekin holding the ginger juice, and pour with confidence. Then loosely cover the bowl, step away, and let chemistry do its thing.
After 15 minutes, the surface of the curd should appear glossy, like porcelain, and it should wobble as a single, cohesive mass when the bowl is gently shaken. Here’s a test many Cantonese cooks use: Lay a spoon on the surface of the curd, and it should rest without breaking through.
If your curd is clumpy or doesn’t fully set, a few things may have gone awry. The ginger may have been too old, the milk too hot or not hot enough, the ramekins too cold—or maybe you couldn’t resist giving the mixture a stir (I’ve been there). The good news is that even an improperly set ginger milk curd is pretty tasty, so by no means would I call it a failure.
I love eating the ginger milk curd right after making it, when it’s still warm and especially aromatic. You can also cover and refrigerate it until chilled—about one to two hours—which firms up the texture and makes for a refreshing treat.
