Rapid characterization and classification of edible oils with ambient ionization mass spectrometry combined with principal component analysis

Food safety is a critical global issue, with food oil fraud being a particularly common occurrence over the past decade. Although gas chromatography/mass spectrometry (GC/MS) is commonly used to determine chemical components in edible oils, sample preparation is often labor-intensive and time-consuming, highlighting the need for an efficient platform to distinguish oil types for food safety. In this study, thermal desorption-electrospray ionization/mass spectrometry (TD-ESI/MS), an ambient ionization mass spectrometry (AIMS), has been employed in the analysis of various chemical compounds with minimal sample preparation. TD-ESI/MS coupled with probe sampling and principal component analysis (PCA) were used to rapidly analyze oil components and classify different oils in the triglyceride mass range (m/z > 800). Eighty-four oil samples were grouped into categories including edible/non-edible, saturated/unsaturated/highly unsaturated, and edible/gutter oil, demonstrating the potential of this analytical platform for food safety applications.