High-Throughput Monitoring of Multiclass Syrup Adulterants in Honey Based on the Oligosaccharide and Polysaccharide Profiles by MALDI Mass Spectrometry.

Abstract

Honey is a natural product that could be easily adulterated with various cheaper sweeteners. In the present study, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was applied for the detection of honey adulteration based on oligosaccharide and polysaccharide profiles. MS-based strategy could reveal the presence of polysaccharides with higher degree of polymerization (DP ≥ 13) and abnormal trends of saccharides in adulterated honey samples, which could be used as indicators for the identification of honey adulteration with high-fructose corn syrup and corn syrup. MS/MS-based strategy was proposed to characterize the difference in the composition of oligosaccharide isomers between honey samples and adulterated ones with corn syrup or invert syrup, in which the [M+Cl]- of disaccharides, trisaccharides, and tetrasaccharides were fragmented to give diagnostic product ion pairs. The method is effective and robust for the high-throughput monitoring of honey adulteration, and provides a new perspective for the identification of other high-carbohydrate foods.