Give an example of an emulsion in culinary practice.

• A. Mayonnaise
• B. Omelette
• C. Grilled cheese
• D. Yogurt

Answer: (A)

An emulsion is a stable mixture of two liquids that don’t normally blend, like oil and water, held together by an emulsifier. Mayonnaise is a perfect example: oil droplets are dispersed through a water-based phase (vinegar or lemon juice and water) with egg yolk providing emulsifiers (lecithin and other phospholipids) that keep the droplets from coalescing. Whisking or blending creates a fine, stable suspension, giving mayonnaise its thick, creamy texture. If the mixture isn’t properly emulsified, the oil can separate out.

Omelette is mainly beaten eggs cooked into a solid mass, not an oil-in-water dispersion. Grilled cheese relies on melted fat and cheese without a dispersed oil phase, and yogurt is a fermented dairy product with a gel-like structure rather than a true oil-in-water emulsion produced by whisking oil into a water phase. So the best example of an emulsion in culinary practice is mayonnaise.