Which statement is true about permanent emulsions?

• A. Mayonnaise is an example of a permanent emulsion.
• B. Vinaigrette is a permanent emulsion.
• C. Bechamel is an example of a permanent emulsion.
• D. Espagnole is an example of a permanent emulsion.

Answer: (A)

Permanent emulsions stay uniformly mixed over time because the chosen emulsifier creates a strong, stable barrier around droplets. Mayonnaise exemplifies this: egg yolk provides lecithin and other emulsifiers that coat oil droplets and hold them in a water-based phase, forming a smooth, stable dispersion with acidity and thorough whisking. This stability means the mixture resists separating under normal conditions.

A vinaigrette, on the other hand, forms a temporary emulsion. The oil and vinegar can blend briefly when shaken or whisked, but without a powerful, durable emulsifier, the mixture separates as droplets collide and coalesce.

Bechamel and espagnole aren’t emulsions at all; bechamel thickens milk with a roux, and espagnole is a brown sauce built from stock and a roux. Their textures come from thickening and reduction, not from dispersing oil droplets in water.