What is a common thickening agent used in sauces?

Cornstarch is a widely used thickening agent in sauces due to its unique properties. When cornstarch is combined with liquid and heated, it undergoes a process called gelatinization. This process allows it to absorb water and swell, which thickens the sauce effectively. Cornstarch creates a clear, glossy finish in sauces, making it particularly popular for gravies and stir-fry sauces.

Additionally, it is versatile and easy to use; it can be mixed with cold water to create a slurry before being added to the hot liquid, which prevents clumping. Its neutral flavor also ensures that it does not alter the taste of the sauce, allowing the primary flavors to shine through.

While flour, gelatin, and arrowroot powder can also serve as thickening agents, they each have distinct characteristics and uses that may limit their effectiveness in certain sauce applications compared to cornstarch.