C1.6 Plant Oils Flashcards
Why do vegetable oils make good fuels?
Contain a lot of energy
Describe the steps of making oil from seeds
-Crushed/pressed -Distilled/decanted/filtered/use a centrifuge
Describe how oil can be obtained by steam distillation
-Water and oil are heated till they evaporate -Oil condenses at different temperature to water.
Describe the chemical test for unsaturated oils
Add bromine water Turns from orange to colourless if oil is unsaturated
Why are oils more suitable for cooking than water
Higher boiling point Cooks food faster (Tastes nicer)
What are the conditions needed to hydrogenate an unsaturated oil
60oC Nickel Catalyst
How does hydrogenating vegetable oils change their properties?
Raises the boiling point Making it solid
Describe how an emulsifier works
- Hydrophilic head is attracted to water
- Hydrophobic tail is attracted to oil
- Oil droplets repel
- Creating suspension of oil throughout the water
Describe the risks of eating too much animal fats
High cholesterol
Causes heart disease