Chiral volatile compounds for the determination of honey authenticity.

The research project aimed to develop a method for the definition of the floral origin of honeys. A large number of unifloral Sicilian honeys were considered and the attention was focused on the volatile chiral terpenes that originate from the plant nectar visited by the bees. For the extraction of volatile constituents SPME extraction technique was chosen: it is the more reliable procedure for stereochemical studies since it reduce the risk of possible racemization for the compounds of interest. The qualitative and quantitative determination of the volatile fraction of honeys are reported and the main terpenes indicated. The enantiomeric ratios of linalool and its derivatives were determined and resulted characteristics for each unifloral honey and not influenced by conditioning, period of storage, etc. On the contrary the amount of the same terpenes was very different within the honeys of the same floral origin. The data, here reported, highlight the possibility to define the authenticity of unifloral honeys through a rapid and reliable method.