Polysaccharides as a marker for detection of corn sugar syrup addition in honey

Honey is a natural product of high quality. However, because of its limited production and of its relatively high price, some beekeepers or unscrupulous traders do not hesitate to modify and falsify this natural product in order to try to increase its market value. Then, these involved falsification practices, for example intentional addition of cheap sugar syrup to honeys, are sometimes difficult to detect. An effective and simple analytical method is proposed in order to detect adulteration in honey by analysis of polysaccharide profiles. Samples were previously treated with reversed-phase solid phase extraction first to remove monosaccharides and small oligosaccharides and second to concentrate simultaneously traces of polysaccharides. A chromatographic separation using anion exchange stationary phase and pulse amperometric detection was further performed. Polysaccharide fingerprints (degree of polymerization from 11 to 17) were shown to be present in laboratory doped samples, and not detectable or present at very low concentrations in the authentic honey samples. Application to acacia, mountain polyfloral and polyfloral honeys enabled readily the detection of fraud resulting from deliberate addition of 1% of corn syrup.