Fats and oils are mixtures, so they have no fixed melting and boiling points.

Fats and oils in nature are a mixture of many substances, and their main component is the ester formed by dehydration of one molecule of glycerol and three molecules of fatty acids, called triglycerides. The main physiological function of fats and oils is to store and supply heat energy, in the metabolism can provide energy than sugar and protein is about twice as high.

Generally at room temperature is a liquid called oil, solid called fat. Fats and oils can come from either animal or vegetable sources, with animal fats and oils generally being solid at room temperature, with good shortening properties, and more commonly used.

Expanded Information:

Classification of Fats and Oils:

Liquid oils are classified according to whether they can be dried in air. can dry in the air are divided into three categories: dry oil, semi-dry oil and non-dry oil. In addition to triglycerides, and contains a small amount of free fatty acids, phospholipids, sterols, pigments and vitamins. The fatty acids in the chemically synthesized or free state are saturated such as lauric acid, corky acid, stearic acid and so on.

There are unsaturated ones such as oleic acid, linoleic acid, linolenic acid and so on. Olein is insoluble in water, soluble in organic solvents such as hydrocarbons, alcohols, ketones, ethers and esters. At higher temperatures, there is a catalyst or the presence of lipolytic enzymes, the hydrolysis of fatty acids and glycerol.

Calcium, potassium and sodium hydroxides are saponified into metal soaps and glycerol. It is also capable of many other chemical reactions such as halogenation, sulfation, sulfonation, oxidation, hydrogenation, deoxygenation, isomerization, polymerization, and pyrolysis.

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