###### Abstract  
The standardization of the botanical origin of honey reflects the commercial value and quality of honey. Nowadays, most consumers are looking for a uniforal 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 (lex) of 330 nm. Subsequently, a score of 81.4% and 79.7%, respectively, at an excitation wavelength (\(\lambda\)ex) 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 hydroxycinamic 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.  
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are both expensive and time-consuming, and, in the case of melissopalynological analyses, require specialized staff. Honey from pine, fir, thyme, and citrus are commercially available in Greece and their demand from consumers worldwide is constantly increasing. They represent about 60-65%, 15%, 10%, and 5% of the country's total annual honey production, respectively. In recent years, numerous spectroscopic methods have been proposed to determine honey types of different botanical origins. The most frequently cited spectroscopic techniques include Fourier-transform infrared spectroscopy (FTIR) [5; 6], near-infrared (NIR) [7], Raman spectroscopy [6; 8], and nuclear magnetic resonance (NMR) [9].  
Fluorescence spectroscopy is simple and 100 to 1000 times more sensitive than other spectroscopical techniques [10]. It has been utilized for the determination of honey adulteration [11; 12; 13], botanical discrimination [14; 15; 16; 17], geographical differentiation [18], and fluorescence marker detection [19; 20]. Various statistical methods have been used in factorial discriminant analysis [15], principal component analysis (PCA) [13; 16; 17; 18], partial least squares (PLS) [21], partial least squares discriminant analysis (PLS-DA) [22; 23], soft independent modeling of class analogy (SIMCA) [16], and hierarchical cluster analysis (HCA) [17] based on fluorescence spectra data.  
Fluorescence excitation-emission matrix (EEM) spectra contain information about a variety of intrinsic fluorochrome compounds, including aromatic amino acids, phenolics, flavins, and Maillard reaction products [13; 14; 24]. EEM includes spectra regions often complicated due to both Raman and Rayleigh scattering. Nevertheless, honey contains phenolic compounds (phenyl carboxylic acids) that do not coincide with scattering, and their concentrations vary depending on their botanical origins [25; 26; 27; 28]. The abovementioned dispersion can be overcome by subtracting a blank EEM or by using the interpolation method [29]. Thus, the right-angle fluorescence spectroscopic technique can be used.  
The aim of this study was the development of an alternative novel method to distinguish honey, based on fluorophore compounds, mainly hydroxycinnamic and other phenyl carboxylic acids. For this purpose, four confirmed unifloral Greek honey varieties were selected.