The pigments of crude cottonseed oils. I. The inhibition of color reversion in crude cottonseed oils

Summary Treatment of freshly prepared crude cottonseed oils with p ‐aminobenzoic acid and subsequent removal of the di‐ p ‐carboxyanilinogossypol formed makes it possible to store the oils at a relatively high temperature (37–38°C.) and for an extended period of time (30 days) without incurring any adverse changes in the refining and bleaching properties of the oils. In addition, a considerable decrease in the refining loss of the crude oil is obtained, and the stability of the bleached oil is not affected by the treatment. Spectrophotometric studies made during all phases of the chemical treatment and during the refining and bleaching procedures show that the p ‐aminobenzoic acid removes almost completely the gossypol‐like pigments which are present in the crude oils and yields oils having the characteristic carotenoid spectrum.