Total unsaponifiables, sterols and tocols of cottonseed oil from Egyptian and other varieties

Abstract

Total unsaponifiables, mainly sterols and tocols, of 14 crude cottonseed oil samples extracted from different cultivars of various origins are reported. Total unsaponifiable matter contents varied between 1.01 and 1.55%. Sterol contents varied between 4245 and 6425 mg/kg, which was mainly beta-sitosterol (76-87%), campesterol (5.4-14.5%) and Delta 5-avenasterol (2.5-7.3%). Total tocol contents were in the range 551-1771 mg/kg, which consisted mainly of alpha-tocopherol (43-58%) and gamma-tocopherol (24-46%). The ratios of beta-sitosterol/campesterol, beta-sitosterol/(campesterol + stigmasterol) and alpha-tocopherol/gamma-tocopherol, which varied from 10.2 to 15.4, 8.8 to 11.9 and 0.77 to 1.25, respectively, could be used as purity criteria for cottonseed oil.