Applications of E-nose, GC-MS, and GC-IMS in tea volatile components analysis

This study reviews applications of Electronic Nose (E-nose), Chromatography-Mass Spectrometry (GC-MS), and Gas Chromatography-Ion Mobility Spectrometry (GC-IMS) in tea industry research. The E-nose offers rapid, non-destructive analysis for real-time quality assessment through odor fingerprint pattern recognition, yet cannot identify or quantify individual compounds. Gas GC-MS, established as the industry gold standard, enables precise qualitative/quantitative analysis of complex volatiles with enhanced efficacy for higher molecular weight compounds. GC-IMS emerges as a user-friendly tool for highly sensitive detection of low molecular weight volatile compounds and rapid two-dimensional gas separation, effectively compensating for GC-MS limitations in trace-level small molecule analysis; however, its compound identification accuracy remains inferior to GC-MS due to incomplete spectral libraries. Collectively, these technologies enable comprehensive tea quality evaluation by characterizing aroma profiles across varieties, authenticating geographical origins, and tracking volatile changes during processing and storage. Their complementary strengths in speed (E-nose), specificity for macromolecules (GC-MS), and sensitivity to small molecules (GC-IMS) establish a multidimensional framework for tea research. This integration provides robust solutions for classification, process optimization, and shelf-life studies, offering theoretical and practical insights to advance quality control, product development, and origin traceability in tea production chains. • First review of three techniques for tea VOC profiling, revealing complementary roles. • Novel GC-IMS mechanisms: ionization, drift dynamics, reduced mobility elucidated. • Provides method-selection guidance for tea VOC analysis practitioners. • Six tea-type processing steps decoded: each stage orchestrates key aroma-forming reactions. • Multi-tech synergy: E-nose screening, GC-MS quantification, GC-IMS real-time trace analysis.