1991 Volume 38 Issue 2 Pages 116-121
Terpeneless (hydrocarbon-free) oils were produced from citrus peel oils by vacuum distillation method-The effects of operating temperature, time and other conditions on the extraction of terpene hydrocarbons were investigated. In an actual run, the operation was carried out at the pressure of 4-4.5mmHg. In binary system (d-limonene+citral), the boiling point remarkably rose as its volume fraction lowered. In ternary system (d-limonene+linalool+citral), the maximum concentration ratio of d-limonene was ca. 1/20 at the extracting temperature of 60°C. on the other hand, the content of linalool in terpeneless oil increased to 40°C, then had a gradual decrease to 70°C and a marked decrease hereafter; that of citral gradually increased with increasing in temperature. Lemon (Citrus limon Burm. f.) peel oil was deterpenified at the most appropriate conditions of 50°C for 30 min to yield the more predominant quality oil consisting of 7.49% d-limonene and 27.2% citral. A similar attempt to deterpenify Valencia orange (Citrus sinensis Osbeck) peel oil was performed at 50°C for 30min. Consequently, the content of linalool in terpeneless oil which highly comtributes to the orange flavor characteristics was ca. 7 times that of native peel oil.
