Infrared spectroscopy in routine quality analysis of honey

Fourier-transform infrared spectroscopy (FT-IR) was used as a rapid, simple and reliable method for quality analysis of honey. More than 1600 samples of honey were analysed using FT-IR and reference methods to develop a partial least-square regression based calibration model for the major components of honey (sugars, proline, free acids, invertase, moisture, hydroxymethylfurfural, pH and electrical conductivity). The coefficient of determination R-2 ranging from 0.84-0.98 indicates an acceptable calibration for most of the parameters. Statistical verification of the spectral analysis in routine analysis showed a high correlation (0.81-0.99), good repeatability (0.84-0.99), no environmental influences (P > 0.05) and no significant statistical differences to the reference methods. This study shows that not only chemical composition but also the physical properties can be determined by FT-IR. The calibrations can be adapted to different analytical standards and honey sources.