Supplemental Table 1. Experimental conditions for Gas Chromatography-Ion Mobility Spectrometry (GC-IMS) analysis

The instrument automatically detected the peak time and intensity of the reactant ion peak to ensure consistency with the standard state. Each spectrum report was an average of 12 scans. The retention index of each compound was calculated using n-ketone C4-C9 as external reference standards. The mixed ketone standard solution was also used to monitor the stability of the peak time and intensity for each compound. Volatile compound identification was based on comparisons with the retention index and drift time in the GC-IMS library. Detailed instrument parameters are provided in Supplemental Table 1.