Honey is one of the foods susceptible to extension and adulteration with exogenous sugars. Whereas there is a well established test for C4 sugar (cane or corn based sysrups) adulteration using EA-IRMS (elemental analyser -isotope ratio mass spectrometry), detection of C3 sugar syrups (rice and beet sugar) is more difficult. In this study, an approach combining Fourier-transform infrared spectroscopy (FTIR) and chemometrics was developed for a rapid screening tool to detect potential adulteration of honey with either rice or corn syrup. A set of 46 authentic and 39 commercial honey samples were collected and adulterated samples of between 1-16% with rice syrup and 3-15% corn syrup were prepared, and their FTIR spectra determined. A single class soft independent modeling of class analogy (SIMCA) model was developed on the spectra of the set of commercial and authentic honey samples. The SIMCA model was externally validated with a set of calibration-independent authentic and commercial honey control samples, and those spiked with rice and corn syrups in the 1-16% concentration range. The authentic and commercial honey test samples were correctly predicted with a 88.3% classification rate. High accuracy was also found in predicting the rice and corn syrup spiked samples above 7% concentration range, yielding 97.6% and 94.8% correct classification rates, respectively.
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