Vegetable ghee is manufactured by the process of

(a) reduction polymerization

(b) oxidation polymerization

(c) hydrogenation

(d) saponification

The correct answer is (c) hydrogenation.

Vegetable ghee, also known as vanaspati, is produced from vegetable oils through a process called hydrogenation. This chemical process converts unsaturated fats, which are liquid at room temperature, into saturated or partially saturated fats, which are solid or semi-solid.

The Process of Hydrogenation

Hydrogenation involves adding hydrogen atoms across the carbon-carbon double bonds present in unsaturated fatty acids (found in oils). This reaction is typically carried out at high temperatures and pressures, using a metal catalyst, most commonly nickel.

The overall reaction can be represented as:

Vegetable Oil (Unsaturated Fat) + H₂ (in presence of Ni catalyst) ⟶ Vegetable Ghee (Saturated Fat)

This process changes the physical properties of the oil, increasing its melting point and making it solid at room temperature, which gives it a butter-like consistency. For example, linoleic acid, a common unsaturated fat in oils, is converted to stearic acid, a saturated fat.