Classification of commercial bitter orange essential oils (Citrus aurantium L.), based on a combination of chemical and sensory analyses of specific odor markers

Abstract

Ten commercial cold-pressed Citrus aurantium L. essential oils (EOs) were previously classified according to their content in twenty-seven key odorants as measured by gas chromatography–mass spectrometry (GC–MS). Principal component analysis and hierarchical cluster analysis performed on odor markers and composition data made it possible to distinguish five EO groups. In addition to chemical measurements, thirty-one subjects participated in a sensory analysis of the sample odors and classified the ten EO samples by means of a free-sorting task. The very good correlation found between chemical and sensory measurements made it possible to confirm that the odor markers previously identified using GC–olfactometry were effective indicators of the EO overall odor. This method combining instrumental and sensory analyses thus appears promising for discriminating and classifying EOs from a given botanical species.

Keywords:

• bitter orange essential oil
• odor volatile compounds
• principal component analysis (PCA)
• hierarchical cluster analysis (HCA)

Acknowledgement

We would like to thank Donald White, native English translator from the A.B.I.E.S. doctoral school, for his kind help in the writing of this article.