Cooking In European cooking, a mixture of butter and flour called a roux is used to thicken liquids to make stews or sauces. In Asian cooking, a similar effect is obtained from a mixture of rice or corn starch and water. These techniques rely on the properties of starches to create simpler mucilaginous saccharides during cooking, which causes the familiar thickening of sauces. This thickening will break down, however, under additional heat. Types of fat include vegetable oils, animal products such as butter and lard, as well as fats from grains, including corn and flax oils. Fats are used in a
Butter lemon juice. Hollandaise and béarnaise sauces are emulsions of egg yolk and melted butter; they are in essence mayonnaises made with butter instead of oil. Hollandaise and béarnaise sauces are stabilized with the powerful emulsifiers in the egg yolks, but butter itself contains enough emulsifiers—mostly remnants of the fat globule membranes—to form a stable emulsion on its own. "Beurre blanc" (white butter) is made by whisking butter into reduced vinegar or wine, forming an emulsion with the texture of thick cream. "Beurre monté" (prepared butter) is melted but still emulsified butter; it lends its name to the practice of "mounting"