Off‐Odor Profiles of Fresh Gastrodia elata Tubers From Five Varieties: Identification of Key Odor–Active Compounds and Their Modulation Through Traditional Processing

Fresh tubers of Gastrodia elata (GE), valued for both their food and medicine properties, have limited applications due to unpleasant off-odor. In this study, five representative fresh GE varieties were analyzed for the first time using quantitative descriptive analysis (QDA). Seven off-odor attributes were identified, with horse urine-like odor being the most intense, followed by acidic and starchy notes. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) detected 67 volatile organic compounds, 17 of which were present in all varieties. Nine shared odor-active compounds were identified by GC-O-MS. Odor activity value (OAV) analysis revealed four key contributors: (E,E)-2,4-decadienal, (E)-2-octenal, 2-phenylacetaldehyde, and p-cresol. Sensory interaction analysis using Feller's additive model demonstrated both binary synergistic and additive effects among these compounds. Traditional processing methods reduced off-odor intensity, with ethanol treatment being the most effective (reducing horse urine-like odor by more than 50%). After processing, the three aldehydes became undetectable, whereas p-cresol levels were substantially decreased, though they still contributed to a residual off-odor. Unlike previous studies that mainly focused on dried GE products, this research characterizes the off-odor profile of fresh GE tubers. It provides a theoretical foundation for regulating off-odor-related gene expression, developing effective deodorization strategies, and facilitating the development of novel GE-based functional foods.