Production, characterization and antioxidant analysis on the Undaria-based alcoholic beverages using response surface method and HS-SPME-GC × GC-TOF-MS

<i>Undaria pinnatifida</i>, a nutrient-rich seaweed, holds potential for the alcoholic beverage industry. This study optimized the ultrasonic processing of <i>Undaria</i> blend liquor (UBL) and the fermentation of <i>Undaria</i> fermented wine (UFW) while identifying volatile components and assessing antioxidant properties. After optimization, UBL had a polysaccharide content (PC) of 0.66 g/L and an alcohol content (AC) of 39.2 % vol, while UFW showed a PC of 9.81 g/L and an AC of 8.3 % vol. HS-SPME-GC × GC-TOF-MS analysis identified 34 characteristic volatile compounds, with esters as the predominant class. UBL was featured by notably high levels of ester compounds, while UFW contained fatty acids leading to distinct flavor profiles. Antioxidant assays revealed that both beverages demonstrated free radical scavenging activity in a dose-dependent manner. These findings highlight the potential of <i>Undaria</i> as a novel resource for developing functional and flavorful alcoholic beverages, contributing to innovation in the food and liquor industries.