Plant oils and their uses WEAVER Flashcards
What is an emulsion?
An emulsion is a mixture of oil and water.
Why are emulsions often used in foods?
To improve taste, appearance and texture of food.
What does an emulsifier consist of?
A hydrophilic (water attracting) part and a hydrophobic (oil attracting) part.
Explain how an emulsifier works.
The hydrophilic part of emulsifier bonds with water while the hydrophobic part bonds with oil stopping the emulsion from separating.
What is it meant by saturated?
A saturated molecule is a molecule with carbon atoms that contain only one bond between carton atoms. (C-C)
What is it meant by unsaturated?
Contain at least one C-C double or triple bonds.
How can you test a fat to show that it is unsaturated? What would you expect to see?
Add bromine water to the fat. If it is unsaturated the bromine water will go from orange/brown to colorless.
Are vegetable oils saturated or unsaturated?
Unsaturated.
Are animal fats saturated or unsaturated?
Saturated.
How can vegetable oils be turned into saturated fats?
By hydrogenation/hardening. Vegetable oils are reacted with hydrogen in the presence of a nickel catalyst to harden them.
What are the problems associated with eating too much saturated fat?
Too much saturated fat can lead to cholesterol building up in arterys causing heart disease.
What are the benefits and drawbacks of using emulsions in food?
Emulsions are used in foods to improve the texture, taste and appearance. However, they contain fats which are high in energy.
What are the impacts on health and diet of eating foods containing lots of vegetable oils?
Vegetable oils contain saturated fats. Animal fats are unsaturated. Eating vegetable oils instead of animal fats is good for your health because they are less likely to cause heart disease.
Explain how sunflower oil can be extracted from sunflower seeds.
The sunflower seeds are first crushed and mixed with water. The mixture is then heated until the oil evaporate. The oils are cooled in a condenser so that they are turned back into liquids and then collected.
Why are vegetable oils important food?
They provide large amounts of energy and offer an alternative to saturated animal fats.
