Abstract：
In order to investigate the effects of multi-frequency ultrasound-assisted immersion freezing (MUIF) on the meat quality of Macrobrachium rosenbergii, tail meat was subjected to different MUIF treatments respectively, namely 20 + 40 kHz (MUIF-20 + 40), 20 + 60 kHz (MUIF-20 + 60), 40 + 60 kHz (MUIF-40 + 60) and 20 + 40 + 60 kHz (MUIF-20 + 40 + 60), and the immersion freezing (IF) as control. Results showed that average diameter of ice crystals was 28 μm in IF, and that was only 8 μm in MUIF-20 + 40 + 60. When compared to IF, MUIF alleviated oxidative deterioration of lipids and proteins, but only at higher ultrasound frequency (MUIF-40 + 60; MUIF-20 + 40 + 60). Carbonyl content of MUIF-20 + 40 + 60 was only 40% of that in IF. Similarly, protein denaturation was inhibited in MUIF (except for MUIF-20 + 40). Transmission electron microscopy showed greater distortion of the ultrastructural components in IF, MUIF-40 + 60, and MUIF-20 + 40 + 60, suggested by bended Z-line. In conclusion, MUIF can be an effective strategy to mitigate mechanical damage and protein deterioration in the meat of Macrobrachium rosenbergii.
摘要：
为了研究多频超声辅助浸泡冷冻(MUIF)对罗氏沼虾肉品质的影响,尾肉分别进行不同的MUIF处理，即20+40kHz(MUIF-20+40)，20+60kHz(MUIF-20+60),40+60kHz(MUIF-40+60)和20+40+60kHz(MUIF-20+40+60)，和浸泡冷冻（IF）作为对照。结果表明，IF中冰晶的平均直径为28μm，在MUIF-20+40+60中只有8μm。与IF相比，MUIF减轻脂质和蛋白质的氧化降解，但仅在较高的超声频率（MUIF-40+60;MUIF-20+40+60）。MUIF-20+40+60的羰基含量仅为IF的40%。同样，MUIF蛋白变性受到抑制(MUIF-20+40除外)。透射电子显微镜显示IF中超微结构成分的更大变形，MUIF-40+60和MUIF-20+40+60，由弯曲的Z线提示。总之,MUIF可以作为减轻罗氏沼虾肉的机械损伤和蛋白质降解的有效策略。
