The value of hydrogenation (hydration) depends on the availability of raw materials in the market. With the exception of coconut oil, palm kernel oil and cocoa butter, in Europe the oils are sold in liquid form, so they are not suitable as plastic grease, eg. ej. to spread in the bread and for the production of bread.
During hydrogenation, the double bond in unsaturated fatty acids binds to hydrogen (gas) in the presence of catalysts (nickel) that accelerate the reaction. Hydrogen is added only to unsaturated fatty acids, and not to trivalent of fatty ester (glycerol). The factors that affect the hydration of the oil are: time, temperature, hydrogen pressure, volume of transport, the catalyst (type, state, concentration), the type of substrate and the way in which the process is carried out.
Hydrated peanut oil (hydrogenated) is a dough white, elastic and slightly rough, that melts in a liquid form and emits a weak smell. The substance is virtually insoluble in water and ethanol but is slightly soluble in ether and in benzene. Unlike refined peanut oil, where oleic and linoleic acid is dominant, peanut oil contains between 3-19% stearic acid and 7-16% palmitic acid, in addition to hydrogenated oleic acid (54-78% ). Linoleic acids (= 10%), eicosanoic (1-3%), docosanoic (1-5%) and tetracosanoic (0.5-3%) are also present, along with very small amounts of eicos-9-enoic acids and cis-docos-13-enoico.
Hydrogenated oil is mainly used as an additive in many foods, as well as in bases for creams and ointments.