• Coating could reduce the accumulation of aldehydes and the accumulation of alcohols during fish storage process. • Coating could slow down the accumulation of off-taste FFAs during fish storage process. • GEO-gelatin coating (GGC) worked better than gelatin coating (GC) in maintaining fish flavor. • Metabolic mechanisms of fish flavor at different storage temperatures were different.

Peptide Phe-Thr-Gly-Met-Leu (FTGML) is a bioactive oligopeptide with tyrosinase inhibitory activity derived from gelatin hydrolysate of grass carp scales. Previous studies have shown that FTGML addition can effectively inhibit mushroom tyrosinase activity in vitro, and also has some effect on the inhibition of melanogenesis in zebrafish in vivo, but the underlying mechanism is not fully understood. In this study, we used FTGML to treat B16F10 melanoma cells, and found a significant inhibition of tyrosinase activity and melanin synthesis. Interestingly, the treatment showed a strong correlation between antioxidant activity and anti-melanin, which was associated with FTGML reducing the involvement of reactive oxygen species in melanin synthesis. Furthermore, FTGML reduced melanogenesis in B16F10 cells by downregulating the cAMP-PI3K/Akt and MAPK pathways (p38 and JNK). These results suggested that FTGML can reduce melanin production in mouse B16F10 melanoma cells through multiple pathways.

Different surfactants (lecithin, Tween‐20, and Tween‐80) were added in composite film during the preparation. Flavor, antimicrobial activity, and physical properties of ginger essential oil ‐gelatin film were investigated, in order to study the effect of surfactants on the properties of film. The flavor of GEO was not detected in the film prepared with Tween‐20 and film prepared with Tween‐80, and these two films exhibited stronger antimicrobial activity; film prepared with lecithin possessed higher value in thickness, elongation at break, water solubility, ΔE and opacity, lower value in water vapor property, and tensile strength; attenuated total reflectance‐Fourier transform infrared spectrum results suggested, Tween‐20 and Tween‐80 enhanced the strength of covalent bond, and lecithin weakened the strength of hydrogen bond; and the result of scanning electron microscope showed that Tween‐20 and Tween‐80 improved the dispersion of oil droplets in film. Therefore, this study suggested that surfactants had an influence on the physical properties and molecular structure of a resulting film; in addition, Tween‐20 and Tween‐80 could reduce the flavor of GEO in film, improving the antimicrobial activity of film.