Abstract: The effects of adding different levels (0.01%, 0.05% and 0.10%) of banana flower extract (BFE) versus dibutylated hydroxy toluene (BHT) on protein oxidation in naturally fermented yak meat sausages were investigated. lys The carbonyl content, Schiff base content, total sulfhydryl content, active sulfhydryl content, surface hydrophobicity, dimeric tyrosine content, endogenous fluorescence intensity and solubility of myofibrillar proteins (MPs) from fermented yak meat sausage were measured at different fermentation times, and the secondary structure and composition of MPs were characterized by Fourier transform infrared (FTIR) spectroscopy, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that compared with the blank control, the addition of BFE decreased the carbonyl group content, Schiff base content, surface hydrophobicity, dimeric tyrosine content and endogenous tryptophan fluorescence intensity of MPs, and increased the total sulfhydryl group content, active sulfhydryl group content and solubility. FTIR spectroscopy showed that the addition of BFE improved the reveal the more stability of the secondary structure of MPs. SDS-PAGE showed that BFE reduced the diffusion of myosin heavy chain and had a protective effect on myosin. This study showed that BFE inhibited protein oxidation in naturally fermented yak sausage, and this effect was positively correlated with BFE concentration, being most pronounced at 0.10% BFE concentration.

Key words: yak meat; banana flower extract; fermented sausage; protein oxidation