What type of dispersion is gravy considered to be?

Gravy is considered a sol, which is a type of colloid where solid particles are dispersed in a liquid. In the case of gravy, the solid particles come from the flour or starch that is used as a thickening agent, as well as from any meat drippings or seasonings. The resulting mixture is a thick liquid where these solid particles remain suspended, giving gravy its characteristic texture and consistency.

Understanding that gravy functions as a sol helps to clarify the physical nature of the dish. It is not a foam, which is a dispersion of gas in a liquid (like whipped cream), nor is it an emulsion, which involves the mixing of two immiscible liquids, like oil and water in a vinaigrette. Gravy also does not fit the definition of a gel, which is a semi-solid mixture that retains a certain structure due to a network of solids holding in the liquid. Thus, recognizing gravy as a sol emphasizes its composition and properties as a food product.