Natural oils and fats are predominantly composed of triglycerides of carboxylic acids of long
chain lengths. Once these carboxylic acids are extracted from the
triglycerides molecules, they are called fatty acids. Thus, fatty acids
are carboxylic acids with a long un-branched aliphatic chain and
some of them have unsaturated carbons. The principal method to
obtain fatty acids from triglycerides is by the trans-esterification
reaction of oils with methanol. The reaction produces fatty acids
along with glycerol