Abstract:

The physico-chemical properties of myofibrillar protein solution treated by ultrasonic were evaluated by particle
diameter, surface hydrophobicity, sulfhydryl content and SDS-PAGE profile. After ultrasonic treatment, the particles of
samples were distributed more uniformly. The mean particle diameter, thermal aggregation, fluorescence intensity and
sulfhydryl content of myofibrillar protein decreased with increasing ultrasonic treatment time. The minimum particle
diameter of myofibrillar protein was 270.3 nm. The surface hydrophobicity of the protein increased, but the molecular
weight showed no significant change. Therefore, myofibrillar protein could be unfolded and the hydrophobic groups were
exposed by ultrasonic treatment; finally the high-order structure was destroyed and the aggregation was promoted although
the primary structure was not changed.

Key words: ultrasonic treatment, myofibrillar protein, particle diameter, thermal aggregation, sulfhydryl groups, molecular weight