Analysis of sulfides in garlic of different origins based on UPLC-QTOF-MS and HPLC combined with chemometrics

Sulfide constitutes a primary active component of garlic, significantly affecting its flavor and overall quality. This research employed ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) for the qualitative analysis of sulfides in garlic. Subsequently, high-performance liquid chromatography equipped with a diode array detector (HPLC-DAD) was utilized to establish a characteristic sulfide fingerprint, which was subsequently integrated with chemometric analysis to identify the key sulfides in garlic. Quantitative analysis of multiple components using a single marker (QAMS) was initially developed based on the established fingerprint profiles to detect the sulfide content. This method addressed the challenge of limited reference materials and demonstrated that the relative correction factors for methiin, isoalliin, and gamma-glutamyl-S-allyl-L-cysteine were 2.109, 1.469, and 1.237, respectively, with alliin serving as the internal reference. In conclusion, this method facilitates the simultaneous analysis of multiple characteristic sulfur components in garlic, thereby providing a substantial theoretical foundation for the quality research of garlic.