Volatile compound changes in dried ginger during sand stir-frying revealed by complementary headspace-based...

This study investigated the processing-dependent changes in volatile compounds of Dried Ginger, Lightly Processed Ginger, Moderately Processed Ginger, and Heavily Processed Ginger using gas chromatography-ion mobility spectrometry (GC-IMS) and headspace gas chromatography-mass spectrometry (HS-GC-MS), combined with multivariate statistical analysis. Moisture content decreased progressively with increasing stir-frying intensity, and volatile contents were expressed on a dry-weight basis. GC-IMS identified 85 volatile compounds, mainly including aldehydes, ketones, alcohols, esters, terpenoids, pyrazines and nitrogen-containing compounds, sulfur-containing compounds, and aromatic compounds. HS-GC-MS detected 101 volatile compounds, among which 33 terpenoid-related compounds represented the largest class in terms of compound number. Stir-frying reshaped the volatile profile of ginger in a class- and compound-specific manner rather than causing a simple linear increase or decrease. GC-IMS results showed that Moderately Processed Ginger had the highest total content of identified volatiles and was enriched in selected aldehydes and terpenoid-related compounds, whereas Heavily Processed Ginger was more closely associated with acetic acid, sulfur-containing compounds, pyrazines, and other thermal-reaction-related volatiles. HS-GC-MS further showed that 55, 63, 71, and 65 volatile compounds were detected in Dried Ginger, Lightly Processed Ginger, Moderately Processed Ginger, and Heavily Processed Ginger, respectively, with the highest number observed in Moderately Processed Ginger. PCA and OPLS-DA distinguished the four processing degrees, and VIP analysis identified 30 GC-IMS markers and 18 HS-GC-MS markers. Fifteen volatile compounds were commonly detected by both platforms, confirming their complementary coverage. These findings provide a scientific basis for volatile marker discovery, quality evaluation, and standardized processing of ginger products.