Authentication of phacelia honeys (Phacelia tanacetifolia) based on a combination of HPLC and HPTLC analyses as well as spectrophotometric measurements

The growing interest in the quality of honey affects customer preferences and consumption trends. Generally, monofloral honeys are more expensive than multifloral honeys, and the price strictly depends on its botanical origin. The increasing popularity of a variety of monofloral brands has led to the increasing number of adulterations and therefore for the need to develop new analytical methods for assessing honey authenticity. The purpose of the present study was to develop a method for the authentication of phacelia honeys on the basis of HPLC and HPTLC analyses and spectrophotometry. The results obtained by spectrophotometric analysis indicated significant differences only between one sample and remaining ones of phacelia honeys. The application of HPLC and HPTLC methods allowed the complete differentiation of Phacelia tanacetifolia honey samples in context of content of other plants pollen. Thus, honeys containing more than 45% pollen from Phacelia tanacetifolia appear to exert more similarities in their respective chromatograms, while the chromatograms of two samples (Ph1 and Ph9), which derived from honey containing majority of pollen from other plants, differed significantly. Therefore, the combination of HPLC and HPTLC fingerprints supported by spectrophotometric measurements seems to be a suitable method for the classification of honey samples.