Margarine is usually made by a process called , in which hydrogen atoms are added to double covalent bonds in the polyunsaturated fatty acids found in vegetable oils.

Hydrogenation

Explanation:

Margarine is made from a process known as hydrogenation of fat. During this process, hydrogen atoms are catalytically (nickel is usually used) added to poly-unsaturated fats to arrive at a saturated solid or semi-solid substance. During this process, skimmed milk is usually added to improve the texture of the product

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explanation: