The pasture system improves natural antioxidants and functional lipids while reducing lipid peroxidation in Ctenopharyngodon idella (grass carp) burgers during storage.

C. idella burgers made from a pasture-based system provide a natural method for producing high-quality fish products, resulting in meat enriched with polyunsaturated fatty acids, particularly EPA and DHA, as well as fat-soluble vitamins and antioxidants. In this study, C. idella meat burgers were made from two types of diets: pasture-based (PS) and grain-based (GS). A total of 36 burgers were stored in plastic trays (three burgers per tray; 12 trays per group), in a refrigeration chamber at 4 °C ± 0.1 °C for 120 h to conduct a shelf-life experiment comparing the meats. Initial fatty acid profile and nutritional composition were determined at 0 h. Additionally, fat-soluble vitamins, antioxidants, TBA, and FRAP were measured at 0, 24, 48, 72, 96, and 120 h. PS burgers exhibited higher concentrations of n-3 LC-PUFAs, vitamins, antioxidants, except for gamma-tocopherol, and FRAP than GS burgers (P < 0.05), while GS burgers had higher TBA and γ-tocopherol (P < 0.05). Both burgers experienced vitamin reduction during storage, with PS burgers maintaining higher concentrations. Vitamin decline correlated with increased oxidation (TBA) in both burger types. These results suggest that pasture-fed burgers have longer shelf life than GS burgers due to reduced oxidation and enhanced stability of bioactive compounds.