On the genuineness of citrus essential oils. Part XXXIV. Detection of added reconstituted bergamot oil in genuine bergamot essential oil by high resolution gas chromatography with chiral capillary columns

MS fragment isotope ratio analysis for evaluation of citrus essential oils by HRGC-MS

To evaluate the origin of citrus essential oils, the isotope ratio of fragment peaks on HRGC-MS of the volatile compounds from various citrus oils was measured. The MS fragment ratio was found by the ratio of fragment peak intensity, m+1/m (m/z). This ratio reflects the isotope effect of volatile compounds, that is, it provides information about locality, quality, and species for essential oils. Multivariate analysis based on the MS fragment ratio of monoterpene hydrocarbons clearly distinguished three citrus species, yuzu, lemon, and lime. The carbonyl fractions were also extracted from citrus essential oils by the sodium hydrogensulfite method. The isotope ratio of MS fragments of octanal, nonanal, and decanal was also examined. The results suggest that there was no significant difference in the individual fragment isotope ratios of the three aldehydes.

Multidimensional Capillary GC-GC for the Analysis of Real Complex Samples. 3. Enantiomeric Distribution of Monoterpene Hydrocarbons and Monoterpene Alcohols of Mandarin Oils

The enantiomeric distribution of beta-pinene, sabinene, limonene, linalool, terpinen-4-ol, and alpha-terpineol in mandarin oils has been determined using a fully-automated, multidimensional, double-oven GC-GC system. This system allows fractions to be multitransferred during the same GC analysis and the use of the two GCs independently when the multitransfer option is not used. The results obtained allowed the characterization of mandarin essential oil and the determination of extraneous oils added to or contaminating the oil.