Volatile profile in the accurate labelling of monofloral honey. The case of lavender and thyme honey

- Volatile analyses complement the pollinic technique if pollen is under-represented.
- Honeys labelled as lavender or thyme are not different in physicochemical factors.
- Volatile compound profile is useful for the classification of lavender honey.
- Volatile compound profile agrees well with the organoleptic analysis.

The proliferation of hybrid plant varieties without pollen, such as lavender, has complicated the classification of specific types of honey. This study evaluated the correlation between the proclaimed type of monofloral honey (lavender or thyme) as appears on the label with the actual percentage of pollen. In addition, physicochemical parameters, colour, olfacto-gustatory profile, and volatile compounds were tested. All of the samples labelled as lavender were wrongly classified according to the usual commercial criteria (minimum 10% of pollen Lavandula spp.). In the case of lavender honey, there was significant agreement between commercial labelling and classification through organoleptic perception (81.8%), and above all between the commercial labelling and the volatile compounds (90.9%). For thyme honey, agreement for both parameters was 90.0%. These results offer compelling evidence that the volatile compounds are useful for the classification of lavender honey with low levels of pollen since this technique agrees well with the organoleptic analysis.