Selected Volatile Markers of Czech Rape and Lime Honeys

The aim of our study was to distinguish between unifloral Czech honeys using target analysis of selected volatile substances. Firstly, 36 honey samples were divided on the basis of relative percentage representation of pollen grains in the particular botanical species into 3 groups: lime (minimum 6%), rape (minimum 70%) and multifloral honeys. Subsequently, nine key volatile substances typical of common plant species in the Czech Republic were selected as markers of botanical origin and evaluated by means of target analysis. It was found out that the lime honeys differed from the rape honeys mainly by a larger representation of p-cymenene and carvacrol and by a smaller representation of 2-phenylethanol; the multifloral honeys were, as expected, very variable in terms of the content of the volatile substances. Linear discriminant analysis indicated 81% accuracy in the classification of honeys according to their botanical origin. Of the 9 studied substances, 2-phenylethanol and carvacrol made a major contribution to sample discrimination.