Refining and fractionating soybean oil with furfural

Abstract

~IE r ]-~l p oductmn of ful ly refined soya oil fractions 1 _ from crude degummed oil by means of liquidliquid fractionation has been accomplished using fu r fu ra l as the selective polar solvent. I t has been known for some time (1, 2) that glyceride oils may be fract ionated on the basis of unsaturat ion within the glyeeride molecule by means of part ial ly miscible, selective, polar soh, cnts. More recently a process has been developed employing these principles for not only fract ionat ing soya oil into a drying oil but also for prepar ing a ful ly refined raffinate for food oil purposes. Fraet ionat ing and refining of soya oil by means of liquid-liquid techniques with fu r fu ra l is dependent upon the fact that the oil is not completely miscible with the solvent at normal temperatures. Therefore, when crude or degummcd soya oil is contacted with fur fura] below the temperature of miscibility two fractions are obtained. The raffinatc or oil predominant phase has concentrated in it the more saturated glycerides and the break constituents with the more unsatura ted glycerides, free f a t ty acids, chlorophyll, other pigments, and unsaponifiable constituents concentrat ing in tile fu r fu ra l predominant extract phase. Although it is impossible to obtain effective separations in a single batch extraction, very remarkable fractionations have been obtained by employing continuous countercurrcnt e x t r a c t i o n with the use of