Unit 2 - 6.2 - Emulsifiers

Question 1

• How is an emulsion formed?
• Give one example of an emulsion

Answer 1

• When tiny droplets of one liquid are suspended within another liquid.
• A mixture of oil and water

Question 2

Describe an Emulsifier

Answer 2

Can be used to prevent non-polar and polar liquids in emulsions from separating into layers

• They can be added to food to stop it from spoiling

Question 3

Describe how emulsifiers can be made for food

Answer 3

By reacting edible oils with glycerol. In the molecules formed, only one or two fatty acid groups are linked to each glycerol backbone.

Question 4

Explain how an emulsifier works

Answer 4

The hydroxyl groups present in the emulsifier are hydrophilic whilst the fatty acid chains are hydrophobic. The hydrophobic fatty acid chains dissolve in oil (non-polar substances) whilst the hydrophilic hydroxyl groups dissolve in water (polar substances), forming a stable emulsion.