The effects of multi-frequency ultrasound on surface decontamination and structural characteristics of large yellow croaker (Pseudosciaena crocea) during refrigerated storage were evaluated. The results of total viable counts (TVCs) and psychrophilic bacteria counts (PBCs) demonstrated that multi-frequency ultrasound retarded the growth of microorganisms. The bacteriostatic effect was positively correlated with the increase of ultrasound frequencies. However, compared with triple-frequency ultrasound (TUS, 20/28/40 kHz) treatment, dual-frequency ultrasound (DUS, 20/28 kHz) treatment had higher water-holding capacity (WHC) and immobilized water content, better texture characteristics, lower pH and total volatile basic nitrogen (TVB-N). Through the results of myofibrillar fragmentation index (MFI), intrinsic fluorescence intensity (IFI) and atomic force microscope (AFM), multi-frequency ultrasound could effectively stabilize the myofibrillar protein structure of refrigerated large yellow croaker, which could maintain better texture characteristics. The effects of DUS were the most significant. Therefore, multi-frequency ultrasound treatment could inhibit the growth of microorganisms and improve the structural characteristics of large yellow croaker during refrigerated storage.

评价多频超声波对大黄鱼冷藏过程中表面去污及结构特征的影响。总活菌计数（TVC）和嗜冷菌计数（PBC）的结果表明，多频超声可抑制微生物的生长。抑菌效果与超声频率的增加呈正相关。然而，与三频超声（TUS，20/28/40 kHz）处理相比，双频超声（DUS，20/28 kHz）处理具有更高的持水能力（WHC）和固定水含量，更好的质地特性，降低 pH 值和总挥发性碱性氮 (TVB-N)。通过肌原纤维断裂指数（MFI）、内源荧光强度（IFI）和原子力显微镜（AFM）的结果表明，多频超声可以有效稳定冷藏大黄鱼的肌原纤维蛋白结构，从而保持更好的质地特性。DUS 的影响最为显着。因此，多频超声波处理可以抑制微生物的生长，改善大黄鱼冷藏过程中的结构特性。