On the genuineness of citrus essential oils. Part X. Research on the composition of essential oils produced from Sicilian lemons using "Pelatrice" and "Sfumatrice" extractors during the entire 1983/84 production season.

The authors report the results of a study made on 488 samples of genuine lemon oil obtained by industrial processing during the 1983/84 season. The lemons, which came from Sicilian lemon-growing areas, were processed using ‘pelatrice’ or ‘sfumatrice’ extractors. Gas chromatography of all samples was effected using capillary columns. The ‘citral’ content and ‘CD’-values were also determined. From the gas chromatography of the oils and the fractions obtained by separation on neutral alumina columns, it has been possible to identify 34 components, which correspond to about 99.3% of the volatile fraction of the essential oil, and to establish the class to which numerous other components belong. The quantitative data obtained by gas chromatography are expressed separately, as the average of the values for each month, for the ‘pelatrice’ and ‘sfumatrice’ extracted oils. The quantitative variations found in the various classes of substances and in the principal components present in the lemon essential oils during the whole season of production are commented upon and the fundamental quantitative differences between ‘pelatrice’ and ‘sfumatrice’ extracted oils are illustrated. The results obtained are compared to those which resulted from an analogous study effected during the 1982/83 citrus production season, and confirm that the composition of lemon essential oil undergoes cyclic variations lasting one year.