“Wok Hei” — a Touch of Love

Food for Thought @ HK Food Court

It’s not so often that I identify a sensation and later learn that there is a name for it. This is common for physical objects because we are able to show the objects to others and ask what they are called. We can’t do the same with a sensation.

The particular taste sensation I identified in fried rice has a name: “wok hei.” (HT to @lanadai and @springmanstefan) Now that I know the name and the science behind it, it’s easier to find. It turns out that it’s not unique to fried rice, but it is easier to identify in fried rice because it’s mostly carbs. It’s a combination of smokiness and caramelization achieved by cooking at an extremely high temperature.

Chris and I went back to Mama’s Kitchen to confirm the existence of wok hei in other dishes. “Shanghai Style Chow Mein” was a perfect candidate because, again, it’s mostly carbs. Sure enough, we can visually identify the caramelization in parts of the noodles.

It’s all making sense to me now.

If you cook any food at a low temperature (an extreme example being sous vide), the outside surface and inside of it would have the same color, flavor, and texture.

Wok hei achieves the exact opposite, but the problem with cooking at an extremely high temperature is that the outside would cook much faster than the inside. By the time the inside is properly cooked, the outside would be burnt. That is why Chinese chefs have to constantly toss the food in the air. By doing so, they are able to balance the amount of caramelization outside and the temperature inside.

This cannot be achieved if you cook too much food at once because 1. it would bring down the temperature of the wok too low for caramelization and smokiness, 2. each element (like each grain of rice) wouldn’t get enough exposure to the wok surface, and 3. it would slow down the tossing process.

As Chris pointed out, this is likely the reason many cheap Chinese restaurants do not have wok hei; because it’s too time-consuming to cook one serving at a time.

I find it incredible that such a subtle difference in how we cook can make such a big difference. Think of everything else we do not notice others do, which adds a touch of love.