Reduction and coordination properties of l-Lysine/l-arginine/l-cysteine for the improvement of the color of cured sausage

Abstract This study investigated how l -lysine/ l -arginine/ l -cysteine improved cured sausage color. Visible detection showed that Mb(Fe2+)NO did not form when MetMb(Fe3+) was treated with a combination of l -lysine and NaNO2, l -arginine and NaNO2, or l -cysteine and NaNO2. Visible spectra and electron paramagnetic resonance (EPR) detection together indicated formation of Mb(Fe2+)O2 when MetMb(Fe3+) was treated with l -lysine, l -arginine, or l -cysteine; Mb(Fe2+)NO was formed when MetMb(Fe3+) was treated with a combination of l -lysine and NO, l -arginine and NO, or l -cysteine and NO. Visible, EPR, and fourier transform infrared results suggested formation of a complex of Mb(Fe2+) and l -cysteine by the coordination of sulfydryl and ferrous porphyrin. Therefore, l -lysine, l -arginine, or l -cysteine can promote the formation of Mb(Fe2+)NO by reducing MetMb(Fe3+) to Mb(Fe2+)O2, and l -cysteine promotes formation of a complex of Mb(Fe2+) and l -cysteine via coordination of sulfydryl and ferrous porphyrin, which may improve cured sausage color.