Absence of aflatoxin from refined vegetable oils.

Abstract

AbstractThe present investigation is the first definitive study of the fate of the aflatoxins in vegetable oils undergoing processing. Crude oils, obtained by solvent extraction or by hydraulic pressing of ground moldy peanuts (not suitable for human consumption), contained only small fractions of the aflatoxin originally present in the peanuts; the meals retained the bulk of the aflatoxin. Conventional alkali refining and washing of the oils reduced aflatoxin content to a range of 10 to 14 ppb. The subsequent bleaching operation essentially eliminated aflatoxin from the oils; the concentrations were now less than 1 ppb. The above results were confirmed using corn oils obtained from corn germ deliberately contaminated in the laboratory withAspergillus flavus. The nonfluorescing forms of aflatoxins, capable of being produced during the alkali refining operations, are also absent from the refined vegetable oils; these aflatoxin derivatives are readily converted to their original form on acidification and thereby measurable by fluorescence, if present.