Dynamic changes in flavor profiles of superfine broccoli powder during dry and wet processing: Insights from E-tongue, E-nose, GC-IMS, GC-MS, and molecular docking.

Processing methods significantly influence the flavor of broccoli powder, with off-flavor development often compromising its sensory quality and consumer acceptance. This study investigated the dynamic changes in flavor characteristics of superfine broccoli powder during dry (hot-air drying followed by dry superfine grinding) and wet processing (wet superfine grinding followed by spray drying). A total of 61 volatile compounds were identified by gas chromatography-ion mobility spectrometry (GC-IMS) and 84 by gas chromatography-mass spectrometry (GC-MS). Meanwhile, 19 and 24 differential volatiles were identified from GC-IMS and GC-MS datasets, respectively. Volatiles in fresh broccoli were predominantly aldehydes, ketones, and alcohols. Dry processing decreased green aldehydic notes and promoted the formation of sulfides and nitriles, resulting in sulfurous and cabbage-like off-flavors. In contrast, wet superfine grinding increased isothiocyanates (ITCs), alcohols, and aldehydes, while spray drying might encapsulate the pungent odor of ITCs within the matrix and enhance green, cucumber-like, and sweet aroma attributes in the final powder. However, the higher ITC content may also contribute to increased bitterness in wet-processed samples. Molecular docking revealed that key aldehydes and ITCs might bind to olfactory receptors via hydrogen bonding and hydrophobic interactions, whereas dimethyl trisulfide might interact mainly through hydrophobic interactions and pi‑sulfur contacts. These findings provide insight into the evolution of volatile compounds during superfine broccoli powder processing, offering a theoretical foundation for flavor optimization in broccoli-based products.