Novel identification strategy for ground coffee adulteration based on UPLC–HRMS oligosaccharide profiling

•Detection of 111 oligosaccharides was accomplished with UPLC–HRMS.•17 oligosaccharides markers were found to distinguish coffee from mixes.•Optimized sensitivity, authority and reliability of identification were obtained.•Estimation of mixes origins and level were achieved.•Commercial ground coffee were identified by this strategy successfully. Coffee is one of the most common and most valuable beverages. According to International Coffee Organization (ICO) reports, the adulteration of coffee for financial reasons is regarded as the most serious threat to the sustainable development of the coffee market. In this work, a novel strategy for adulteration identification in ground coffee was developed based on UPLC–HRMS oligosaccharide profiling. Along with integrated statistical analysis, 17 oligosaccharide composition were identified as markers for the identification of soybeans and rice in ground coffee. This strategy, validated by manual mixtures, optimized both the reliability and authority of adulteration identification. Rice and soybean adulterants present in ground coffee in amounts as low as 5% were identified and evaluated. Some commercial ground coffees were also successfully tested using this strategy.