Antioxidant Properties of a Dihydromyricetin-Rich Extract from Vine Tea (Ampelopsis grossedentata) in Menhaden Oil

Preventing oxidative deterioration of fish oil is a significant challenge for the food industry. Natural antioxidants are widely incorporated into foods to prevent oxidation and extend shelf life. Vine tea (Ampelopsis grossedentata) extract has been shown to have antioxidant activity in vegetable oils, but the efficacy in fish oil is unknown. The goal of our study was to test the antioxidant activity of vine tea extract (VTE) and compare it with other natural antioxidants (rosemary extract - RME, green tea extract - GTE, grape seed extract - GSE, ascorbyl palmitate - AP, and citric acid - CA) in tocopherol stabilized menhaden oil. Baseline levels of alpha, gamma, and delta tocopherols were 0.18mg/g, 0.37mg/g, and 0.14mg/g, respectively. VTE delayed menhaden oil oxidation when stored at 40°C for eight days as determined by primary and secondary oxidation products. Mixtures of VTE and RME and their combinations with AP and CA more effectively improved stability of menhaden oil containing tocopherols than VTE alone. Our results show that VTE is an effective natural antioxidant in menhaden oil, especially in combination with RME.