Increased antioxidant and antimicrobial activities of lemongrass and cinnamon essential oils with tea polyphenols and its application in the preservation of marine fish

Plant essential oils have great potential to become a new generation of marine fish preservatives, and the key to the application of essential oil in fresh-keeping is to improve its cost performance. In this study, the combined effect of 0.008 g/mL lemongrass essential oils and 0.01 g/mL cinnamon essential oils with different concentration (0, 0.005, 0.01, 0.03, 0.05 g/mL) of tea polyphenols on the antioxidant activity and antimicrobial activity in vitro, and application in marine fish preservation was studied. The in vitro tests showed that the combination of essential oils with tea polyphenols increased the antioxidant and antimicrobial activities compared with the essential oils or tea polyphenols alone. During the preservation of the marine fish Dusky Spinefoot, the combination of essential oils with tea polyphenols slightly inhibited microbial growth, but greatly reduced the visible decay on the surface of fish flavour deterioration and biogenic amine production. Antimicrobial activities were also observed in films prepared combining essential oil and tea polyphenols. These combined effects are meaningful and provide prospects for expanding the application of essential oil and developing a new hurdle technology for marine fish storage.