fats and oils Flashcards
What are the uses of fats and oils?
Fats and oils are a concentrated source of energy essential for the transport and storage of fat-soluble vitamins in the body.
What does unsaturated mean?
Contains C=C double bonds.
Fats and oils: saturated or unsaturated?
Solid fats tend to be saturated (few C=C double bonds) and liquid oils tend to be unsaturated (higher number of C=C double bonds).
How to distinguish between fats and oils…
Unsaturated compounds quickly decolourise bromine solution. Bromine adds across double bonds in addition reaction.
The greater number of double bonds, the more bromine decolourised.
What are fats and oils?
Naturally occuring esters of the alcohol glycerol (propan-1,2,3-triol) and long chain carboxylic acids known as fatty acids.
3 moles of fatty acids to 1 mole of glycerol,k three ester links.
Why are fats solid at room temperature?
The fatty acids have a low degree of unsaturation so they can be arranged closely together. This means that there are lots of LDF’s and fats are solids at room temperature as molecules are held closer together.
Why are oils solid at room temperature?
The fatty acids have a higher degree of unsaturation so have a disorder arrangement.
Harder for LDF’s to form between molecules so fewer in number and therefore oils are liquid at room temperature.
Hardening of oils.
Adding hydrogen across the double bonds makes oils less saturated, it uses a nickel catalyst.
