cornstarch slurry

A cornstarch slurry is a mixture of cornstarch (a refined starch extracted from corn kernels) suspended in liquid—typically cold water or another cold liquid such as broth, juice, or milk. Cornstarch itself is the endosperm of the corn kernel (Zea mays), processed into a fine, white, odorless powder consisting primarily of amylose and amylopectin carbohydrates. When mixed with cold liquid, cornstarch particles remain suspended; upon heating, the starch granules absorb liquid, swell, and gelatinize, creating viscosity and thickening sauces, soups, and other preparations.\n\nThe slurry preparation method is essential to cornstarch's thickening function. Whisking cornstarch into cold liquid before adding it to hot liquids prevents clumping and ensures even dispersion. This technique is fundamental across many cuisines, particularly in Asian cooking traditions.

Cornstarch slurry is primarily used as a thickening agent in sauces, gravies, soups, stews, and braised dishes. It is especially prevalent in East Asian cuisines—Chinese stir-fries, Vietnamese canh, and Korean stews rely heavily on cornstarch slurry for silky, glossy sauce consistency. The slurry is added near the end of cooking to achieve desired thickness without prolonged simmering. It produces a more translucent result than flour-based roux and works well in acidic preparations like sweet-and-sour sauces. Cornstarch slurry also stabilizes creamy soups, marinades, and glazes, and is sometimes used to coat meat or vegetables before cooking for a delicate crust.