Analytical Discrimination of the Cold-Pressed Oils of Mandarins and their Hybrids

Abstract

Volatile compositions of the cold-pressed peel oils of a Satsuma mandarin cultivar, from Japan, and four other cultivars of mandarin hybrids such as Temple, Orlando, Kara and Minneola obtained from Ethiopia and Kenya were analyzed by capillary GC and GC/MS, without prior separation. Satsuma mandarin and Temple were characterized by high concentrations of (E,E)-α-farnesene and linalool, respectively. The enantiomeric distribution of α-pinene, β-pinene, sabinene, limonene, linalool, citronellal and α-terpineol was studied by simple and reliable enantioselective GC methods involving either a chiral capillary column or an on-line coupling of non-chiral and chiral capillary columns. The (+)-enantiomers of most of the components in all of the analyzed oils were present in excess, except for linalool and citronellal in the oils of Satsuma mandarin and Temple, respectively. Cold-pressed oils of Satsuma mandarin were found to contain about 75% enantiomeric excess of (3R)-(-)-linalool instead of (3S)-(+)-linalool excess, as was found in the oils of other mandarin cultivars and hybrids.