Impact of Maturity on Volatile Flavor Compounds and Sensory Quality of Distilled Spirit from Hetianhong Table Grapes

This study examined the effect of grape ripening on the distillate quality of Hetianhong table grapes across three stages of maturity (17, 20, and 24 °Brix). Through the application of HS-SPME-GC-MS, a total of 72 volatile aroma compounds were identified. As the grapes matured from 17 to 24 °Brix, there was an 8.48-fold increase in volatile fatty acids, accompanied by a rise in ester concentrations, while significant reductions were observed in naphthalene derivatives, aldehydes/ketones, and terpenols. Notably, the distillate at 20 °Brix demonstrated the highest concentration of higher alcohols, the richest aroma and superior sensory attributes. The 2-methyl-1-propanol concentration was 15.70 times greater at 20 °Brix than at 24 °Brix, while octanoic acid concentration was 97.93 times higher at 20 °Brix compared to 17 °Brix. Overall, Hetianhong table grapes are ideal for distilled spirits, with optimal maturity modulating the final flavor profile. This research supports value-added processing of these grapes.