Egg yolk is one type of emulsifier.
Regardless of how hard you shake and stir, you won't be able to mix water and oil. The two ingredients have different polarities and therefore will not combine. After your mixing, the oil layer will eventually come together and float on top of the water layer. To get the two ingredients to combine, you need to add an emulsifier. An emulsifier will reduce the surface tension of the oil and water and allow them to mix. The mixture is called an emulsion. Oil and water emulsions are used in beauty products, medicines and cooking.
Instructions
1. Drop an egg yolk into a mixing bowl. Use a hand mixer to beat the egg.
2. Continue beating the egg as you pour in 1/4 cup of water. Beat the mixture until thoroughly combined.
3. Warm the mixture over low heat. Continue to stir until the mixture is smooth. Remove the pan from the heat.
4. Add in the oil slowly, no more than one or two tablespoons at a time. After each addition, stir the mixture well until the oil is thoroughly incorporated into it.
Tags: until thoroughly
