Application of FTIR-HATR spectroscopy and multivariate analysis to the quantification of adulterants in Mexican honeys

Fourier transform infrared (FTIR) spectroscopy with attenuated total reflectance (ATR) accessory was used to quantify three different adulterants (corn syrup, high fructose corn syrup and inverted sugar) in honeys of four different locations of México (Chiapas, Oaxaca, Estado de México and Morelos). The optimal calibrations for the three adulterants were developed with partial least squares (PLS). The developed models were validated with different independent data sets being the standard error of prediction (SEP) between 1.5 and 2.1 for corn syrup, 2.1-3.0 for high fructose corn syrup and 1.4-2.5 for inverted sugar, showing the applicability of these models to the detection and quantification of adulterants in honey bee. Classification of the Mexican honeys from the four different states was carried out with soft independent modeling class analogy giving 100% correct classification rate and no false positive results were obtained.