Process of hydrogenation

Hydrogenation is the process of adding hydrogen to unsaturated fatty acids to reduce the number of double bond.

Points of unsaturation in fatty acid are weak spots that are vulnerable to attack by oxygen. When the unsaturated points on the oils of food are oxidized, the oils become rancid and the food tastes ‘off’.

The purpose of hydrogenation is twofold:
*To covert liquid oils to semisolid or plastic fats

*To increase the thermal and oxidative stability of the fat, and thus the shelf life Hydrogenation raises the melting point of the fat, but in addition to this the fat is changed.

Hydrogenation of unsaturated fatty acid occurs when hydrogen has reacted with the oil under controlled conditions of temperature and pressure and in the presence of a nickel catalyst.

Hydrogenation is accomplished in a reactor where hydrogen gas is bubble though the oil at a suitable temperature and pressure in the present of catalyst.

The catalyst accelerates the ration but is not consumed in the reaction. The resulting product is more saturated and more spreadable than the original oil.

It is also more resistant to damage from oxidation or breakdown from high cooking temperature. 

Hydrogenated oil has a high smoking point, so it is suitable for the purpose such as frying.

Hydrogenated fats are used in some biscuits, cakes, pastries, margarines, vegetable shortening and other processing foods.
Process of hydrogenation