GED Science Practice

What is the function of an emulsifier?

1. any of several complex proteins that act as catalysts in specific biochemical reactions

2. a surface-active agent that promotes the formation of an emulsion

3. the mechanical process of wearing or grinding something down

4. the passage between the pharynx and the stomach

The correct answer is: a surface-active agent that promotes the formation of an emulsion

An emulsifier serves as a surface-active agent that promotes the formation of an emulsion, which is a mixture of two or more liquids that typically do not mix well, such as oil and water. Emulsifiers help stabilize these mixtures by reducing the surface tension between the liquids, allowing them to blend more easily. This is crucial in various food products, cosmetics, and pharmaceuticals, where maintaining a stable mixture improves texture, appearance, and shelf life. By lowering the interfacial tension, emulsifiers create a barrier that prevents the dispersed phase (like oil droplets) from coalescing, thus maintaining an even distribution throughout the mixture. This principle is why emulsifiers play such an essential role in products such as salad dressings, mayonnaise, and creams, ensuring a consistent and pleasing quality. Understanding the role of emulsifiers is vital in food science and various industrial applications.