If you’ve ever been in or near a restaurant kitchen in Sichuan, then you know the distinct and delicious smell of caiziyou (菜籽油, càizǐyóu), the cooking oil of choice in southwest China. Made from roasted oil seeds, minimally processed, it has a natural dark-amber color and unique, vegetal smell. As Fuchsia Dunlop puts it in The Food of Sichuan, “It has a glorious, toasty aroma that adds an extra dimension to chili oil and all kinds of dishes.”  

“Caiziyou,” roughly pronounced “sigh-zuh yo,” simply means vegetable oil, and in Sichuan vegetable oil has traditionally meant rapeseed oil. Rapeseed is the unfortunate English name for Brassica napus, which is known as youcai in Mandarin and yuchoy in Cantonese. Yuchoy is one of the tastiest Chinese greens and also produces bright yellow flowers and an oil-rich seed. 

Chefs in Sichuan generally use caiziyou when making chili oil, and say that it is necessary to heat caiziyou to its smoke point and then let it cool a bit before making chili oil, to tame the stronger notes of the oil. Caiziyou is central to chili oil and the “red-oil” dressings made from it due not only to the fragrance and taste it imparts but also to its adhesive quality. 

Sichuan’s Signature Caiziyou (Roasted Rapeseed Oil)

Although rapeseed oil is one of the oldest edible oils in the world, some strains have a high percentage of toxic-in-high-doses erucic acid, which is why Canada bred a new, low-acid strain of the plant in the 1970s and called it canola, standing for Canada Oil, Low Acid. Later strains of canola were genetically modified to withstand Roundup, and GMO canola has come to dominate the world market. As is most cooking oil, canola is fully refined, bleached and deodorized to produce a neutral oil for North American tastes.

In contrast, the best caiziyou is made from low-erucic-acid, non-GMO seeds and is expeller pressed instead of chemically processed. It is definitely not made to be neutral, as the seeds are roasted to accentuate the flavor and it retains its natural color, fragrance and taste. It boasts the same homemade taste as the oil long made in the Sichuan countryside. 

Our partner Chinese Cooking Demystified helps explain and promote this little-known but quintessential Sichuan ingredient

Sichuan Caiziyou (Roasted Rapeseed Oil)

Sichuan food without caiziyou is like Italian food without olive oil. If you have the douban, pickles, sauces and huajiao, but something still tastes like it’s missing, it just may be caiziyou. With a color like liquid gold and an intensely aromatic, deeply toasted nutty flavor, this oil will transport you straight to Sichuan.

Almost never seen in the U.S., this caiziyou requires extra effort and cost to import. The Zhongliang brand of caiziyou is a specialty oil made in Chongqing by COFCO, one of China’s largest, state-owned corporations and its largest producer of both canola oil and Sichuan-style roasted rapeseed oil. Zhongliang caiziyou is expeller-pressed from non-GMO seeds.

Non-GMO, Vegan, Gluten-Free

Buy premium caiziyou (roasted rapeseed oil)
Caiziyou

Caiziyou Chili Oil Recipes

Using Caiziyou in Chili Oil/Hongyou

There’s one thing about caiziyou’s centrality to chili oil and 红油 (hóngyóu) dressings only Chinese sources will tell you: It has superior adhesive quality. This is especially relevant for cold Sichuan dishes where hongyou (literally, the red oil produced from making chili oil) dominates. Ultimately, the better an oil clings to food, the better its application as a delivery vessel for fragrance and flavor.

Incidentally, caiziyou’s erucic acid content (see Chinese Cooking Demystified’s video above) makes it the most viscous of rapeseed-derived oils (including canola) and other everyday oils like olive, coconut, corn and soybean. Viscosity matters because hongyou coating behaves differently as a cold-dish adhesive “running” on your food’s surface. At lower temperatures, caiziyou is more highly viscous and less runny, making it the ideal hongyou vessel. This is a no-brainer for Sichuan’s plethora of cold dishes, called “liangban cai,” which are often tossed in such a hongyou dressing.

aromatic chili oil

Liangban Recipes With Caiziyou Chili Oil

Cooking and Storage Tips

Store caiziyou in a cool, dark place away from direct sunlight and heat sources. Exposure to light and heat can lead to oxidation and degradation of the oil’s quality. Keep the oil away from moisture and humidity.

Caiziyou differs from heavily refined, processed vegetable oils. Below 410-464F (210-240C), the rapeseed oil will smell “raw” or grassy. To rid this raw quality, Chinese chefs always heat the oil until smoking and allow it to cool before using.

When stir-frying, we definitely follow the lead of Sichuan chefs and use caiziyou or half caiziyou and half rendered pork lard. With that combination you’ve already got a wonderful base of flavor before you’ve even begun cooking. 

Ready to Taste the Real Sichuan? Get the DIY Mala Chili Crisp Kit

DIY chili crisp kit

We bundled the hard-to-source ingredients that are must-haves for mala chili crisp, the spicy, numbing, crunchy, umami-in-a-jar “it” condiment that enlivens almost any dish you put it on. The star ingredient, roasted rapeseed oil, or caiziyou, is an essential component of Sichuan gastronomy. There is no substitute for its fragrance or use.

The kit also includes an exclusive chili crisp recipe based on Chinese Internet research and weeks of testing both ingredients and methods. The instructions are also applicable to making aromatic chili oil, which has far less “crisp” and is used in noodle dishes such as dandanmian and in most sauces for Sichuan cold dishes and salads. 

The functional Bormioli Rocco resealable glass beauty holds 17 ounces, so your creation will be not only better and fresher, it will be significantly bigger than store-bought chili crisp and chili oil, which ranges from 5 to 8 ounces. The kit makes two 17-ounce batches of chili crisp or aromatic chili oil. Use leftovers from the full-size products to make other Sichuan dishes. 

see The diy mala chili crisp kit

All How to Cook With Caiziyou (Roasted Rapeseed Oil)