Abstract: In this paper, the effect of flavonoids from gordon euryale seeds on the structure of heat-treated myofibrillar proteins extracted from duck thigh meat was investigated by molecular fluorescence spectroscopy, near-infrared spectroscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and changes in the sensory quality of marinated duck thighs with different mass ratios of flavonoids to myofibrillar proteins were explored. It was shown that when the mass ratio of myofibrillar proteins and flavonoids was 1 : 9, and the heat treatment time was 30 min, the highest sensory score (85 out of 100 points) was obtained, together with the lowest β-turn proportion (12.24%); the proportion of random coil structure was 9.02%, lower than that in the control group (11.56%). Moreover, the protein components were not significantly degraded. To sum up, adding appropriate amounts of flavonoids from gordon euryale seeds effectively prevented the secondary structures of myofibrillar proteins from being damaged by heat treatment and maintained the structural integrity thereby improving the sensory quality of marinated duck thighs.

Key words: flavonoids from gordon euryale seeds; myofibrillar protein; heat treatment; protein structure