Ethanol-Assisted Spice Extraction as an Industrial Flavoring Strategy for Chinese Braised Soup: Insights Into...

Spices are essential contributors to the aroma of Chinese braised foods, but traditional industrial application methods, such as adding loose spices or using spice bags, face critical limitations. These include inefficient release of hydrophobic aroma compounds, poor flavor consistency across batches, and lack of precise control, ultimately compromising product quality and reproducibility. In this study, we developed a spice flavor extraction strategy, and the produced spice extract solution facilitates standardized and precisely dosed application, as well as quality control of related products in industrial applications. HS-GC-MS identified 46-67 volatile compounds per spice extract. Phenylpropanoids, monoterpenes, and sesquiterpenes were identified as the molecules most strongly correlated with solvent polarity. An 80% (v/v) ethanol solution was identified as the optimal extraction solvent, balancing flavor recovery and cost efficiency. After cooking as a Chinese braised soup, the spice extract concentrate exhibited significantly higher volatile abundance than traditional loose-spice and spice-bag methods, with a total volatile content 7.25-fold higher than that of the spice-bag sample. GC-MS, GC-IMS, and odor activity value combined analysis confirmed anethole, terpinen-4-ol, γ-terpinene, linalool, and D-limonene as key aroma-active compounds in the braised soup. Lastly, the braised soup was prepared by industrial braising with duck wings; the spices extraction group retained markedly higher total volatiles and showed lower flavor loss (36.2%) compared to loose-spice processing (91.2%). Electronic tongue analysis further demonstrated that the extraction method reduced astringency and after-astringency compared to traditional methods without increasing bitterness. These findings demonstrate that ethanol-assisted spice extraction could improve spice utilization and support standardized flavor regulation in braised food processing.