Application of ultrasound treatment for improving the physicochemical, functional and rheological properties of myofibrillar proteins

The aim of this study was to evaluate the impact of duration (10, 20 and 30 min) and power (100 and 300 W) of high-intensity ultrasound (20 kHz) on physicochemical properties of beef myofibrillar proteins in order to investigate novel process for modification of its functional characteristics. Results showed that augmentation of duration and power of ultrasound led to enhance pH. Also, the water holding capacity and gel strength were improved by increasing pH. The highest value in pH, reactive sulfhydryl content, water holding capacity and gel strength was obtained in sample subjected to 30 min of ultrasound at 300 W. The particle size distribution of the proteins was decreased after ultrasound treatment because of the cavitation force of ultrasound waves. In this circumstance, an improvement of emulsifying properties can be obtained. Ultrasonic waves had significant effects on the rheological properties of myofibrillar proteins. Treated samples were more elastic and stiffer than control, although the inverse trend was observed after 30 min treatment at each power. Finally, a reducing trend in viscosity was observed by increasing time and power of sonication. Ultrasonic treatment could successfully improve functional properties with effect on physicochemical properties of myofibrillar proteins.