Enhancing frozen fish quality: strategically applied ultrasound frequencies on preservation outcomes of large yellow croaker (Larimichthys crocea)

Ultrasound-assisted freezing (UAF) has proven effective in enhancing the quality of frozen fish, with acoustic frequency playing a crucial role in ultrasonic cavitation. Dual-frequency has a stronger cavitation effect than single-frequency. Our research compared the effects of different ultrasonic application modes during freezing on the quality of large yellow croaker ( Larimichthys crocea ) and myofibrillar protein (MP) structure. We found that dual-frequency simultaneous UAF not only improved freezing efficiency but also resulted in superior water-holding capacity (WHC), texture, and lower levels of total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARS) compared to single-frequency and dual-frequency sequential UAF. Dual-frequency simultaneous UAF also preserved higher Ca 2+ -ATPase activity, sulfhydryl content, and more stable MP secondary structures while reducing carbonyl content. Collectively, dual-frequency simultaneous UAF accelerates the freezing process, enhances fish quality, and maintains the integrity of the MP structure.