The Use of Right Angle Fluorescence Spectroscopy to Distinguish the Botanical Origin of Greek Common Honey Varieties

Marinos Xagoraris,Panagiota-Kyriaki Revelou,Petros A. Tarantilis,Eleftherios Alissandrakis,Christos S. Pappas

doi:10.3390/app11094047

Abstract

The standardization of the botanical origin of honey reflects the commercial value and quality of honey. Nowadays, most consumers are looking for a unifloral honey. The aim of the present study was to develop a novel method for honey classification using chemometric models based on phenolic compounds analyzed with right angle fluorescence spectroscopy, coupled with stepwise linear discriminant analysis (LDA). The deconstructed spectrum from three-dimensional-emission excitation matrix (3D-EEM) spectra provided a correct classification score of 94.9% calibration and cross-validation at an excitation wavelength (λex) of 330 nm. Subsequently, a score of 81.4% and 79.7%, respectively, at an excitation wavelength (λex) of 360 nm was achieved. Each chemometric model confirmed its power through the external validation with a score of 82.1% for both. Differentiation could be correlated with hydroxycinnamic and hydroxybenzoic acids, which absorb in this region of the spectrum. Fluorescence spectroscopy constitutes a rapid and sensitive technique, which, when combined with the stepwise algorithm and LDA method, can be used as a reliable and predictive authentication tool for honey. This study indicates that the developed methodology is a promising technique for determination of the botanical origin of common Greek honey varieties. Our long-term ambition is to support producers and suppliers to remain in a competitive national and international market.

Highlights

Introduction published maps and institutional affilIn the European Union (EU), beekeeping remains an ever-expanding sector, with the EU establishing itself as the second largest global producer of honey after China, producing280,000 tons every year [1].Based on their botanical origins, each variant of unifloral honey commands a premium price due to its organoleptic properties; related to the interest of consumers regarding correctly labeling a honey’s origin
The EU safeguards authenticity by enforcing strict legislation establishing physicochemical characteristics [2], which Greece reinforces by enacting stricter physicochemical characteristics and melissopalynological analyses [3]
The resulting chemometric models, using linear discriminant analysis (LDA), which are based on physicochemical parameters, are unreliable [4]

Summary

Introduction

280,000 tons every year [1]. Based on their botanical origins, each variant of unifloral honey commands a premium price due to its organoleptic properties; related to the interest of consumers regarding correctly labeling a honey’s origin. The EU safeguards authenticity by enforcing strict legislation establishing physicochemical characteristics [2], which Greece reinforces by enacting stricter physicochemical characteristics and melissopalynological analyses [3]. Irrespective of these enforced regulations to ascertain the exact origin via scientific means, a number of these parameters are somewhat correlated with large-scale dispersion. It should be considered that these types of analyses iations

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Conclusion