2 thiobarbituric acid

Duck oil was offered by Lichen Oil Co., Ltd. (Weifang, China). Novozym 435 lipase (10,000 U/g) was provided by Novozymes Biotechnology Co., Ltd. (Tianjin, China). 2-thiobarbituric acid (≥98.5%) was obtained by Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). All other chemical reagents were of analytical or guaranteed purity.

The same batch of frozen oysters from South China Sea, with good commodity quality were obtained from Raoping Yujie Food Industry Co., Ltd. (Guanngdong, China), transported to the laboratory through a cold chain, stored at −20 °C, then transferred to 4 °C the night before the experiment for defrosting. RO (the content of carnosic acid was 15.36%, w/w) was obtained from Kalsec Co, Ltd. (Shanghai, China). Fish 4-HNE ELISA Kit was obtained from Beijing Kangpu Tongchuang Co, Ltd. (Beijing, China). 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) were obtained from Macklin Regent Co, Ltd. (China). Trichloroacetic acid (TCA) was from Shanghai Aladdin Reagent Inc. (Shanghai, China). Sodium dihydrogen phosphate dihydrate, 2-thiobarbituric acid (TBA), absolute ethanol (analytical reagent), Tween-80, and sodium dihydrogen phosphate dodecahydrate (Sinopharm Chemical Regent Co, Ltd., Beijing, China) were used.

The EWP powder used in this study was provided by Jiangsu Kangde Egg Industry Co., Ltd. (Nantong, China). Sunflower oil was purchased from a local supermarket in Wuxi, China. 1,1,3,3-Tetraethoxypropane was purchased from Shanghai Macleans Biochemical Technology Co., Ltd. (Shanghai, China). XG was purchased from Sigma-Aldrich, Co., Ltd. (St. Louis, MO, USA). Nile red, Rhodamine B, barium chloride, ammonium thiocyanate, isopropylbenzene hydrogen peroxide, ferrous sulfate, trichloroacetic acid, 2-thiobarbituric acid and other chemical reagents were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). All chemical reagents were of analytical grade.