The process of straightening an unsaturated fatty acid to create a more solid fat that resists rancidity is called

The correct answer is hydrogenation

Explanation:

The process of straightening an unsaturated fatty to produce more saturated and more solid fat is called hydrogenation. In the process of hydrogenation, the hydrogen is added to the liquid unsaturated fats to convert them into solid fat.  

Hydrogenation helps in increasing the shelf life of the oil by resisting rancidity. Most of the trans fat in our diet is made from the process of hydrogenation. Fully hydrogenated oil contains a very small amount of trans fat and is better than trans fat which is partially hydrogenated.

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