Differentiation of Greek Thyme Honeys According to Geographical Origin Based on the Combination of Phenolic Compounds and Conventional Quality Parameters Using Chemometrics

The aim of the present study was to differentiate Greek thyme honeys according to geographical origin, based on phenolic compound content and conventional physicochemical parameters using MANOVA and Linear Discriminant Analysis. Thirty-five thyme honey samples were collected during the harvesting period 2011 from four different regions in Greece (Irakleio, Hania, Kefalonia and Lakonia) known to produce thyme honey of good quality. The analysis of phenolic compounds (quercetin, myricetin, kaempferol, chrysin, and syringic acid) was performed by high pressure liquid chromatography. Conventional quality parameter analysis included the determination of the following: pH, free, lactonic and total acidity, electrical conductivity, moisture, ash, as well as lactonic/free acidity ratio and colour parameters L*, a*, b*. Using five phenolic compounds and 11 conventional quality parameters, thyme honey samples were satisfactorily classified (91.2 % correct prediction) according to geographical origin.