What process involves adding hydrogen to unsaturated fats to convert them into saturated fats?

Hydrogenation is the process of adding hydrogen to unsaturated fats, which reduces the number of double bonds between carbon atoms in the fatty acid chains. This chemical reaction transforms unsaturated fats, which are typically liquid at room temperature, into saturated fats that are usually solid or semi-solid. This process is commonly used in the food industry to improve the texture and shelf life of certain products, such as margarine and processed foods.

Unsaturated fats contain one or more double bonds in their chemical structure, while saturated fats do not have any double bonds. The addition of hydrogen effectively converts these double bonds into single bonds, thus saturating the fat molecules. This modification can also alter the melting point and chemical stability of the fats.

The other options refer to different chemical processes: oxidation involves the loss of electrons and can lead to rancidity in fats; hydration is the addition of water, typically seen in the context of chemical reactions involving water intake; and fermentation is a metabolic process that converts sugar to acids, gases, or alcohol using microorganisms. Each of these processes serves different functions and does not involve the conversion of unsaturated fats to saturated fats as hydrogenation does.