All vegetable oil extraction processes have certain objectives in common. They aim to maximize the oil yield, minimize damage to the oil and meal and minimize undesirable impurities in both fractions.
The preparations of raw materials includes husking, cleaning, crushing and conditioning.
Seed extraction is achieved by pressing and/or by extraction with hexane. Oils such as palm and olive, on the other hand are pressed out of the soft fruit.
After extraction, the liquid oil is skimmed; after pressing, the oil is filtered; and after solvent extraction, the crude oil is separated and the solvent is evaporated and recovered.
The residual meal or cake, which has a high protein content is usually used as a protein concentrate to feed livestock and poultry.
Crude oil refining includes degumming, neutralization, bleaching, deodorization, and further refining.
Processing of crude oils to finished edible food products is dictated by factors of consumer preference, flavor and oxidative stability characteristics and modification of liquid oils to hardened products, i.e. margarine and shortening.
Processing of vegetable oil