Quantitative study of the oxidative discoloration of ethyl linoleate. II. Oxidation on a cotton substrate

The atmospheric oxidation of ethyl linoleate on a cotton substrate has been studied at 22 and 50°. The concentrations of conjugated diene hydroperoxide, conjugated triene diene ketone, and the development of a yellow coloration were obtained as functions of time by reflectance spectrophotometry at 234, 268/275 and 350 mμ respectively. Both the primary and secondary stages of the oxidation were affected by pretreating the cotton with sodium carboxymethyl cellulose and sodium ethylenediaminetetra‐acetate. A qualitative similarity exists between the extinction coefficients obtained from this investigation and those calculated from a bulk‐phase oxidation, but reflectance measurements at 234 mμ indicate that the conjugated hydroperoxide formed in the initial stages of the oxidation is considerably less stable on the cotton substrate than in the bulk‐ester phase.