Impact of organic acids on aroma release in light-flavor Baijiu: A focus on key aroma-active compounds

Organic acids are critical flavor contributors in light-flavor Baijiu (LFB). The binding of organic acids and volatile compounds may affect the release of flavor in Baijiu. In this study, the effects of different concentrations of lactic acid, hexanoic acid, butyric acid, and acetic acid on the release of key aroma-active compounds in LFB were investigated. Twenty volatile compounds were identified as key aroma-active compounds in four LFB samples using odor activity values combined with aroma recombination, and omission experiment methods. Furthermore, as the concentrations of organic acids were increased in the simulated LFB solution, significant changes in the release of key aroma-active compounds occurred. The addition of lactic acid from 0.5-fold to 5-fold resulted in all key aroma-active compounds exhibiting stronger releases, especially the addition of a 3-fold concentration of lactic increased the release of key esters to about twice. In contrast, the effect of hexanoic acid, butyric acid, and acetic acid on the release of key aroma-active compounds showed a concentration-dependent trend. This suggests that the specific structures of volatiles and organic acids alter the intermolecular interactions between them, thereby altering the aroma release. The results reveal that different organic acids alter the overall aroma profile by affecting the release of volatile compounds in the LFB matrix.