Effects of tocopherol nanoemulsion addition on fish sausage properties and fatty acid oxidation

Quality of fish sausages can be compromised due to fatty acid oxidation. The effects of tocopherol nanoemulsions (NEs) and coarse emulsions (CEs) on the physicochemical properties and lipid oxidation of fish sausages were assessed during 16-day storage at 4 °C. The addition of 250 and 500 mg/kg tocopherol NEs not only improved fish sausages' quality during cold storage but also effectively retarded lipid oxidation, as evidenced by the significantly lower peroxide value and higher polyunsaturated fatty acid content. Omega-6 fatty acids of tocopherol NEs added sausages were maintained at 31.01% for NE250 and 29.59% for NE500 on day 16. However, CEs did not exert significant antioxidant activity. The particle size of the tocopherol NEs remained below 500 nm when stored at 4 °C for 16 days while the particle size of tocopherol CEs increased from 4 to 6 μm. The smaller particle size, even distribution, and stability of tocopherol NEs might explain the better antioxidant activity of them in fish sausages. Interestingly, NEs encapsulated with 250 mg/kg tocopherol are effective to delay the lipid oxidation and improve the fish sausages quality without altering their texture properties during cold storage.