Name two emulsions used in sauces and give an example of each.

• A. Mayonnaise (permanent emulsion) and vinaigrette (temporary emulsion)
• B. Bechamel (emulsion) and Velouté (emulsion)
• C. Tomato sauce and Hollandaise
• D. Espagnole and Demi-glace

Answer: (A)

Emulsions in sauces hinge on keeping droplets of one liquid dispersed in another liquid that doesn’t mix with it, stabilized by an emulsifier or by strong mixing. A permanent emulsion stays mixed over time because the droplets are held in suspension. Mayonnaise is a classic example: oil dispersed in a water-based phase and stabilized by the egg yolk’s lecithin (often with a dash of mustard), giving a thick, creamy sauce that remains stable with proper technique. A temporary emulsion is formed when oil is whisked into an acid like vinegar, creating a uniform mixture that will separate if left standing; vinaigrette is the standard example here. It can be stabilized briefly by vigorous whisking or a small amount of mustard, but it won’t stay emulsified as long as mayonnaise does. So the pair that demonstrates both types with clear examples is mayonnaise and vinaigrette. Other options don’t fit as well because they aren’t emulsions in the same way (some are thickened with starch, and while Hollandaise is an emulsion, the best pairing to show both stable and temporary emulsions is mayonnaise and vinaigrette).