Abstract:

A method for simultaneous screening and determination of steviol glycosides in Chinese liquor and beverages by hydrophilic interaction ultra-high performance liquid chromatography-quadrupole/Orbitrap high resolution mass spectrometry (HILIC-UHPLC-Q/Orbitrap HRMS) was developed. In addition, the MS fragment path ways of steviol glycosides were characterized. The sample was diluted and filtrated before analysis, separated by a Waters Xbridge Amide column (150 mm×4.6 mm, 3.5 μm), and determined via UHPLC-Q/Orbitrap HRMS. The analytes were electronic using electro spray ion source in the negative mode, and the data were collected using full mass scan and data-dependent MS² scan. Good linear relationships (10-1000 μg/L) were obtained. The limits of detection ranged from 0.3 to 20 μg/L. The mean recoveries varied from 81.9% to 106% at the spiked levels of 10-100 μg/kg, and the relative standard deviations ranged from 0.1% to 9.3% (n=3). Two characteristic fragment ions of steviol glycosides were identified by the analysis of fragment ion spectra of eight types of steviol glycosides standards. Non-targeted screening of unknown steviol glycosides in samples was carried out on the basis of the identified characteristic fragment ions. The proposed method is comprehensive, accurate, and sensitive for rapid screening and determination of sweeteners in food samples.

Key words: high resolution mass spectrometry (HRMS), non-targeted screening, steviol glycosides, ultra high performance liquid chromatography (UHPLC)