An optimized green preparation method for the successful application of Raman spectroscopy in honey studies

Raman spectroscopy represents an emerging technique for food authentication being a fast, reliable analytical method, requiring a minimum sample preparation step. Anyway, as in the case of any analytical techniques, there are some limitations which need to be properly assessed before applying this method in honey authentication. In this regard, the aim of this study consisted in the development of a simple working protocol, for honey sample preparation, which can simultaneously overcome the main limitations of Raman spectroscopy in honey studies, such as crystallization and fluorescence. Thus, in this work, a new green sample preparation method is proposed, discussed and its robustness is tested. It has been demonstrated that through honey dilution, in distilled water, reliable and reproductible spectra could be obtained, allowing the investigation of different types of honey. The main advantage of the method consists in the simultaneously overcoming of the most significant limitations of Raman spectroscopy employment in honey studies, such as crystallization and fluorescence, by a simple 1:1 w/v dilution of honey in distilled water.