An emulsified sauce is a sauce in which two liquids are blended into a stable mixture. Which of the following is an example?

• A. Gravy
• B. Stock
• C. Beurre monté
• D. Mayonnaise

Answer: (D)

Emulsified sauces stay together because a substance acts to keep tiny droplets of one liquid dispersed evenly in another, preventing separation. Mayonnaise is the quintessential example: it is a stable oil-in-water emulsion created by whisking oil into an aqueous mixture of egg yolk, vinegar or lemon juice, and spices. The egg yolk provides lecithin, a natural emulsifier with molecules that have both water-loving and oil-loving ends. This coats the oil droplets and holds them in suspension, giving a thick, creamy texture that stays uniform rather than separating. The acid not only flavors the sauce but also helps stabilize the emulsion when it’s made correctly. Other options aren’t emulsions in the same way: stock is just a thin liquid, gravy is typically thickened with starch and juices rather than held together as droplets, and beurre monté is a warm emulsion of butter and water but mayonnaise is the classic cold emulsified sauce students learn to recognize.