Complementary Use of Multi-dimensional Gas Chromatography and Proton Transfer Reaction Mass Spectrometry for Identification of Rapeseed Oil Quality Indicators

Abstract

The change of concentration of various volatiles generated during frying may be an indicator of oil quality. Chemical compounds such as aldehydes, ketones, alcohols and carboxyl acids are the products of oxidation during thermal degradation of edible oils. Shown in this work is a complementary use of GC×GC-TOFMS and PTR-MS for the detection and determination of quality indicators of rapeseed oil. The former technique was used for the identification of potential markers and the latter for their quantitative determination. As a result of the GC×GC analysis, it was determined that 2-pentanone, heptane, octane, 1-heptanol and nonanal can be considered indicators of thermal degradation of rapeseed oil. Using PTR-MS, it was possible to monitor the concentration of these volatile indicators in real time. Based on the results of the analysis and of the reference method, it was concluded that 1-heptanol is best suited for the role of a quality indicator of thermal degradation of rapeseed oil.