Abstract
This study investigated the role of lipid oxidation in off-flavor development during pea protein (PP) extraction via alkaline solubilization and isoelectric precipitation and its mitigation through antioxidant treatment. Four antioxidants (coffee extract, caffeic acid, catechins, and Duralox®) were screened by tracking oxidation markers: malondialdehyde (MDA), hydroxyoctadecadienoic acids (HODE), and volatile compounds. Catechins and Duralox® effectively reduced the formation of HODE and beany volatiles in PP. Further optimization explored the dosage effect of catechins (250-2000 ppm), Duralox® (0.25-2.0%), and their combinations (25:75, 50:50, 75:25). Higher catechins concentrations nearly eliminated hexanal formation by suppressing lipoxygenase activity and free radicals generation, indicating dual enzymatic and non-enzymatic inhibition. Duralox® limited primary oxidation but increased radicals and volatiles at higher doses. Sensory analysis confirmed that catechins reduced beany off-flavors in PP but introduced bitterness and astringency. Overall, these findings highlight the potential of targeted antioxidant treatments to mitigate lipid oxidation-driven off-flavor formation during PP extraction.