Which function acts as an emulsifier by binding fat and water, as in mayonnaise?

Which function acts as an emulsifier by binding fat and water, as in mayonnaise?

• A. Binder
• B. Foams
• C. Leavening
• D. Emulsifier

Answer: (D)

Emulsification is about merging fat (oil) with water into a stable mixture. An emulsifier has both a water-loving (hydrophilic) part and an oil-loving (lipophilic) part, so it sits at the oil–water interface and lowers the surface tension that would cause droplets to merge. In mayonnaise, egg yolk provides lecithin, which acts as this emulsifier, binding fat and water to form a smooth, stable emulsion rather than separating. Without an emulsifier, shaking oil and water together only creates a temporary mix that soon separates. The other functions describe different roles: a binder just helps hold ingredients together, foams relate to incorporating or stabilizing air, and leavening produces gas to make dough rise. The emulsifier is the one that specifically stabilizes the fat–water mixture, making it the best answer.

Emulsification is about merging fat (oil) with water into a stable mixture. An emulsifier has both a water-loving (hydrophilic) part and an oil-loving (lipophilic) part, so it sits at the oil–water interface and lowers the surface tension that would cause droplets to merge. In mayonnaise, egg yolk provides lecithin, which acts as this emulsifier, binding fat and water to form a smooth, stable emulsion rather than separating. Without an emulsifier, shaking oil and water together only creates a temporary mix that soon separates. The other functions describe different roles: a binder just helps hold ingredients together, foams relate to incorporating or stabilizing air, and leavening produces gas to make dough rise. The emulsifier is the one that specifically stabilizes the fat–water mixture, making it the best answer.