Flashcards in C1 - Plant Oils Deck (14)
How can oils be extracted from plants?
Through pressing or distillation.
Why are vegetable oils important foods?
They contain a lot of energy and are nutritious.
What are unsaturated oils?
Unsaturated oils contain double carbon bonds.
Give a disadvantage of using vegetable oils for cooking.
The food absorbs the oil which is high in energy which could be stored as fat.
Give two advantages of using vegetable oils for cooking.
Food tends to taste better and cooks more quickly.
How are vegetable oils hardened?
Reacting the oil with hydrogen increases the boiling point making it solid at room temperature.
What is an emulsion?
A mixture of oil and water held together by an emulsifier.
Give three examples of emulsions.
What is an emulsifier?
A substance that prevents the oil and water in an emulsion separating.
How do emulsifiers work?
The emulsifier has a hydrophobic hydrocarbon chain "tail" which dissolves in the oil droplets. There is also a hydrophilic charged "head" to the molecule which dissolves in the water. The two parts stop the parts of the emulsion separating.
What is an E number?
A food additive approved by the EU.
Give a disadvantage to using emulsifiers in food.
People are more tempted to eat fatty foods.
Give an advantage of using emulsifiers in food.
Emulsifiers improve the texture of food making emulsions more palatable.