Emulsions Flashcards
What doesn’t dissolve in water?
Oil
What happens when you mix oil and water?
You make an emulsion which are made up of los of droplets of one liquid suspended in another liquid.
What is an oil in water emulsion?
Droplets of oil in water
What is an water in oil emulsion?
Droplets of water in oil
What property do emulsions have compared to their substances (that make up the emulsion)?
Emulsions are thicker
Give examples of an oil-in-water emulsion
Milk
Cream
Whipped cream and Ice cream (include air)
Moisturising lotions
What helps water and oils mix?
Emulsifiers
What are emulsifiers?
Molecules with one part that’s extracted to water and another part that’s attracted to oil/fat
What’s the name for the part of the emulsifier attracted to water?
Hydrophilic - latches on to water molecules
What’s the name for the part of the emulsifier attracted to oil/fats?
Hydrophobic - latches on to oil molecules
Describe what emulsifiers do in a mixture of water and oil
When you shake the water together with a bit of emulsifier, the oil forms droplets, surrounded by a coating of emulsifier…with the hydrophilic part facing outwards. Other oil droplets are repelled by the hydrophilic part which water molecules latch on to.
What are the advantages of emulsifiers?
1) they stop emulsions from separating out and this gives them a longer shelf-life
2) They allow food companies to produce food that’s lower in fat but still has a good texture
What’s the disadvantage of emulsifiers?
Some people are allergic to certain emulsifiers.
What is a common emulsifier?
Egg yolk
