| Abstract
| - The potential of front-face fluorescence spectroscopy for the authentication of unifloral and polyfloralhoney types (n = 57 samples) previously classified using traditional methods such as chemical, pollen,and sensory analysis was evaluated. Emission spectra were recorded between 280 and 480 nm(excit: 250 nm), 305 and 500 nm (excit: 290 nm), and 380 and 600 nm (excit: 373 nm) directly onhoney samples. In addition, excitation spectra (290−440 nm) were recorded with the emissionmeasured at 450 nm. A total of four different spectral data sets were considered for data analysis.After normalization of the spectra, chemometric evaluation of the spectral data was carried out usingprincipal component analysis (PCA) and linear discriminant analysis (LDA). The rate of correctclassification ranged from 36% to 100% by using single spectral data sets (250, 290, 373, 450 nm)and from 73% to 100% by combining these four data sets. For alpine polyfloral honey and the unifloralvarieties investigated (acacia, alpine rose, honeydew, chestnut, and rape), correct classification rangedfrom 96% to 100%. This preliminary study indicates that front-face fluorescence spectroscopy is apromising technique for the authentication of the botanical origin of honey. It is nondestructive, rapid,easy to use, and inexpensive. The use of additional excitation wavelengths between 320 and 440nm could increase the correct classification of the less characteristic fluorescent varieties. Keywords: Honey; unifloral; botanical origin; authentication; front-face fluorescence spectroscopy;Robinia pseudoacacia; Rhododendron ferrugineum; Castanea sativa; Brassica napus var. oleifera
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