Characterization of the volatile and sensory profile of instant Pu-erh tea using GC × GC-TOFMS and descriptive sensory analysis

Volatile compounds and sensory characteristics of instant Pu-erh teas (IPET) produced through the spray-drying process were evaluated by using headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS) and descriptive sensory analysis (DSA), and compared with Pu-erh tea (PET). A total of 208 and 204 volatiles were identified in IPET and PET, respectively. Through independent samples t -test, 98 and 55 compounds showed highly significant differences ( P  ≤ 0.01) and significant differences (0.01 <  P  ≤ 0.05) between IPET and PET, respectively. Meanwhile, 158 compounds were defined to interpret the differences between IPET and PET using variable importance in the projection (VIP) value. Moreover，seven aroma attributes were identified through DSA. The results showed that IPET had the higher intensity of floral, fruity, sweet, and caramel-like descriptor, while PET demonstrated higher intensity of stale/musty and woody attributes.