Characterization of Cold-Pressed Key and Persian Lime Oils by Gas Chromatography, Gas Chromatography/Mass Spectroscopy, High-Performance Liquid Chromatography, and Physicochemical Indices

Abstract

The physicochemical indices and the qualitative and quantitative composition of the volatile fraction and the oxygenated heterocyclic fraction of cold-pressed Key lime oil (types A and B) and Persian lime oil are reported. The volatile fraction of Persian lime oil is characterized by a higher content of limonene, γ-terpinene, esters, and monoterpene aldehydes and a lower content of β-pinene + sabinene, sesquiterpenes, and aliphatic aldehydes than Key lime oils. Oxypeucedanin was not detected in Key lime oil type A, while it is present in Key lime oil type B and Persian lime oil. This is probably due to the extraction technology used for Key lime oil type A, which allows the essential oil to come into contact with the juice. Under these conditions, the epoxy ring of oxypeucedanin is opened by hydrolysis to form oxypeucedanin hydrate. Keywords: Citrus aurantifolia Swingle; cold-pressed Key lime oil; type A; type B; Citrus latifolia Tanaka; cold-pressed Persian lime oil; volatile fraction; limonene; γ-terpinene; β-pinene + sabinene; coumarins; psoralens; oxypeucedanin