What is the process in which hydrogen is introduced to vegetable oils to make them saturated known as?

Hint: Vegetable oils are unsaturated compounds, which are alkenes. In these compounds addition of hydrogen results in the saturation by adding up to double bonds and making them single bonds. Through this vegetable oils are converted into vegetable ghee. This is a type of additional reaction.

Complete answer:
Vegetable oil contains highly unsaturated bonds in their chemical composition. Therefore, vegetable oils are unsaturated products and have less shelf life. It is due to the fact that at the site of unsaturation, the double bonds are reactive and easily react in presence of oxygen and get oxidized creating a rancid vegetable oil.
Due to the above reason, hydrogen is introduced in vegetable oils to make them saturated products. The hydrogen is introduced in the form of an additional reaction. The reaction is known as hydrogenation reaction. Hydrogen is added on the double bonds in the presence of a catalyst like nickel, platinum and palladium. The example for hydrogenation reaction is,
${{H}_{2}}C=C{{H}_{2}}+{{H}_{2}}\xrightarrow{Ni,\Delta }{{H}_{3}}C-C{{H}_{3}}$
The unsaturated ethene, in the presence of nickel and heat, has hydrogen added and converts to ethane.
Hence, the process in which hydrogen is introduced to vegetable oils to make them saturated is known as hydrogenation.

Note:
The hydrogenation of vegetable oils produces vegetable ghee. The unsaturated form of fats are more beneficial as compared to the saturated form. A catalyst is a compound that enhances the rate of the reaction without taking part in it, therefore, hydrogenation is processed by nickel, platinum and palladium as catalysts.