Edible Oil Refinery Plant Manufacturers

Edible oil refining stages and equipment

Refining crude vegetable oil involves a series of processing stages, each targeting specific impurities. Degumming removes phospholipids (gums) using water or acid treatment; centrifuges separate the hydrated gums. Neutralisation (also called caustic refining or alkali refining) reacts the oil with sodium hydroxide solution to convert free fatty acids (FFA) into soaps, which are then separated by centrifuge and washed out. Bleaching adsorbs colour bodies, trace metals, and oxidation products using activated bleaching earth; the spent earth is filtered out through a pressure leaf filter. Deodorisation (deodourisation) is a steam distillation process at high temperature (200–250°C) and high vacuum that removes volatile off-flavour compounds, residual FFA, and pesticide residues. After deodorisation the oil is cooled, filtered, and transferred to storage. Some oils — particularly palm oil — also require fractionation (controlled crystallisation and filtration) to separate liquid olein from solid stearin.