Quality and origin characterisation of Portuguese, Greek, Oceanian, and Asian honey, based on poly-parametric analysis hand in hand with dimension reduction and classification techniques

Chestnut, heather, honeydew, multifloral, orange blossom and thyme honey samples obtained either from beekeepers or supermarkets from Portugal, Greece, Oceania and Asia, were characterised by means of poly-parametric analysis: palynological, degrees Brix, moisture, pH, electrical conductivity, free acidity, total dissolved solids, salinity, vitamin C, specific weight, CIELAB colour parameters, Pfund and colour intensity determinations, along with bio-activity and volatile compounds analyses were carried out. Results showed that the botanical and geographical origin of honey samples had a similar impact on the determined parameters, using dimension reduction and classification techniques. Among them, moisture, degrees Brix, electrical conductivity, salinity, pH, colour parameters L* and b*, colour intensity, 1-hydroxy-2-propanone, benzaldehyde, 2-ethyl-1-hexanol, HMF and benzeneacetaldehyde were the potential markers related to the geographical and botanical origin of six honey varieties from different countries. Finally, the identification of methylglyoxal in Portuguese honeydew honey creates the basis for new research on the isolation and identification of this compound in European honey.