We eat fat and oil every day, they provide energy and building blocks of hormone to us.
Triglycerides is the basic fat molecule of both edible fat and oil. Each fat molecule consists of three long chains with carbon backbone, called fatty acids, all attached to one glycerol molecule (See pictures below). These fatty acids determine the properties of the molecule hence the fat and oil formed.
Are characterised by two primary molecular properties:
A “saturated” fatty acid like stearic acid and palmitic acid has no double bond and every carbon atom in the chain is completely saturated with hydrogen atoms.
Oleic acid (18 carbons, 1 double bond)
Alpha-Linoleic acid (18 carbons, 3 double bond)
Linoleic acid (18 carbons, 2 double bond)
Oleic has one double bond hence it is known as “mono-unsaturated”.
Linoleate has more than one double bonds therefore it is known as “poly-unsaturated”.
Unsaturated fatty acids are not packed efficiently due to the presence of double bonds. These doubles bonds almost always* produce kinks in the fatty acid that make the packing harder. It is like packing bendy straws in to a box, you cannot do it better than the straight straws. As a result, oils such as Olive oil, Sunflower oil and Canola oil tend to stay liquid at room temperature.
* Fatty acids with double bonds that not making a kinks is commonly known as “trans fats”.
