Effect of ultrasonic thawing on gel properties of tuna myofibrillar proteins

The effects of ultrasonication time (0, 6, 12, 18, and 24 min) at 280 W and ultrasonic power (0, 160, 280, and 400 W) for 12 min on properties of tuna myofibrillar protein (MP) gels were investigated. Gel qualities including gel strength, texture, water holding capability, and moisture migration were studied. The structure of MP gels was observed by sulfhydryl groups, surface hydrophobicity, ultraviolet absorption spectrum, particle size, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that the protein structure maintains stabilization at 280 W for 12 min, and the quality of MP gels was improved after ultrasonic treatments. The r-value of the second-derivative UV spectra indicated that the microenvironment of the tyrosine was changed. In addition, the particle size decreased, and SDS-PAGE showed that myosin heavy chain and actin bands were degraded after ultrasonic treatments. These results indicated the potential for the further application of ultrasonic treatments in MP gels. Practical applications It is important to choose a suitable thawing method for frozen aquatic products. In order to reduce the quality fission of frozen products during the thawing, different ultrasonic powers and times were adopted in this work. The objectives of this study to evaluate the gel properties and structure of tuna myofibrillar proteins. The work showed that ultrasonic thawing is a feasible and effective method for frozen aquatic food.