What thickening agent is frequently used in soups?

The thickening agent commonly used in soups is cornstarch. Cornstarch is valued for its ability to quickly thicken liquids while creating a smooth texture. When mixed with a cold liquid before being added to the hot soup, it forms a slurry that prevents clumping. Once the soup reaches a sufficient temperature, the starch granules swell, absorbing water and creating a thicker consistency.

While flour can also be used as a thickening agent, it often leads to a cloudier appearance and requires longer cooking times to eliminate the raw flour taste. Gelatin and agar-agar serve different purposes; gelatin is primarily used for gelling and setting, while agar-agar is used in vegetarian and vegan dishes for similar gelling functions, neither of which suitably thickens soups in the same manner as cornstarch.