Comparative study on the improvement of off-flavors in Baijiu by different activated carbon for alcoholic beverages

To explore the effectiveness of activated carbon on the quality of Baijiu with off-flavors, 11 types of activated carbon (#1~#11) for alcoholic beverages were selected to treat off-flavors Baijiu. The physicochemical indicators, flavor components, and sensory scores of the Baijiu before and after treatment were compared. A quality evaluation model for aroma was constructed using principal component analysis, and the effect of different activated carbons on the aroma quality of Baijiu was analyzed. The structure and properties of the optimal activated carbon were characterized using low-temperature nitrogen adsorption, scanning electron microscopy, infrared spectroscopy, and other methods. The results showed that different activated carbons had different degrees of adsorption on the foreign flavor components in Baijiu. The total ester retention rate of #1 activated carbon was 93.9%, and the total acid retention rate was 99.2%, which had better retention effect of flavor substances, and had the optimal effect on improving cellar flavor, removing bitterness, spiciness and odor of Baijiu. #1 activated carbon had the highest score for its principal components. The results showed that the average internal pore size of #1 activated carbon was 2.692 nm, the total pore volume was 0.933 cm³/g, and the specific surface area was 1350.825 m²/g, which showed that it had large specific surface area, good pore size distribution, which was the excellent adsorption medium for the treatment of Baijiu with off-flavors.