Environmental Parameter Drivers of Odor-Active Compound Fingerprinting and Sensory Profile in Waterborne-Coated Manchurian Ash (Fraxinus mandshurica Rupr.)

Wood products made from Manchurian ash are widely used as furniture and decorations, particularly waterborne-coated Manchurian ash (Fraxinus mandshurica Rupr.). However, while waterborne coatings offer less air pollution, their odor emission dynamics under different environmental conditions remain poorly understood. To address these gaps, this study systematically analyzed 28-day volatile organic compounds (VOCs) and very volatile organic compounds (VVOCs) release profiles under controlled temperature, relative humidity, and air exchange rate-to-loading factor ratios (AER/Ls), using thermal desorption–gas chromatography–mass spectrometry/olfactometry (TD-GC-MS/O). Eighteen key odor-active compounds (OACs) were identified, comprising 11 wood-derived and seven coating components, exhibiting eight odor attributes: disinfectant-like, aromatic, tobacco-like, unpleasant, vinegar-like, flowery, sweety, and alcohol-like. The dominant attributes were disinfectant-like and aromatic. The results showed that temperature accelerated release rates and shortened equilibrium time, while increasing concentrations and odor intensity. Relative humidity prolonged equilibrium, with stage-dependent concentration effects, yet consistent odor intensity rise. Higher AER/L reduced equilibrium time and concentrations through dilution-dominated dynamics despite accelerated release rates from increased pressure differentials. These findings indicated that synergistic high-temperature (40 °C)/high-humidity (60% RH) conditions accelerate odorant emission, while optimized ventilation (AER/L 0.5 m3·m−2·h−1) ensures effective mitigation. The findings will inform strategies to reduce odor impact and advance eco-efficient finishing technologies for wood products.