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Vegetable Oils - Emulsions.

What is an Emulsion?

Vegetable oils do not dissolve in water.
Oil will float on top of water because it is less dense
but tiny little drops (called droplets) of oil can be
dispersed in water to form a mixture called an emulsion.

An emulsion is thicker (has a higher viscosity) than
either oil or water. Examples of emulsions in food are
ice cream, milk and salad dressings.
Emulsions are also used to make cosmetics and paints.

How is an Emulsion made?

An emulsion can be made just by shaking oil and
water together. Shaking the two together vigorously
breaks up
the oil into droplets and the droplets
become scattered (dispersed) throughout the water.

Emulsion of Oil Droplets in Water

When you stop shaking, the oil and water mixture will
separate and in a little time the oil will float back up to the
surface of the water. You can make the oil droplets
stay in the water for a longer time by using an emulsifier.
This is called making the emulsion more stable.

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