College of Food Science and Engineering, Dalian Ocean University, Dalian, China.
Department of Food Production and Environmental Management, Faculty of Agriculture, Iwate University, Morioka, Iwate, Japan.
J Food Sci. 2022 Jan;87(1):206-215. doi: 10.1111/1750-3841.16007. Epub 2021 Dec 29.
The purpose of this study was to reveal the role of mitochondria in indicating a change in the freshness of the adductor muscle of Mizuhopecten yessoensis during cold storage and hardening. The adductor muscle hardens after 96 h of cold storage and reaches the maximum degree of hardening in 6 h. In this study, after hardening (102 h), the muscle fiber structure obviously broke and curled, and the sarcomere structure disappeared at 150 h. After hardening (102 h), the morphology of the mitochondria changed, including swelling, cristea breaking and membrane structure disappearance. The arginine phosphate content decreased gradually from the initial 4.618 to 1.306 µmol/g at 48 h, and there was no further obvious change. The ATP content decreased from 6.02 to 1.07 µmol/g in 120 h. The mitochondrial membrane potential (Δφ) was measured by a fluorescence method (JC-1). The changes in freshness could be divided into three classes according to the Δφ difference between the mitochondria in the adductor muscle after adding ADP and CCCP. Mitochondrial function was complete from 0 to 6 h; mitochondrial function began to decline at 6 to 48 h; and mitochondrial function completely disappeared after 48 h. The results showed that the mitochondrial membrane potential compared with other indicators could more sensitively reflect the changes in freshness during the cold storage hardening process of the adductor muscle. PRACTICAL APPLICATION: It is very important to interprete the post-mortem energy metabolism for controlling the muscle quality of Yesso scallop. The K value which was developed based on ATP-related compounds is widely used in evaluating the freshness of seafood. Mitochondria is the main sites of cellular energy metabolism and the changes of its structure and activity can sensitively reflect the quality changes in muscle cell. It is expected to develop a more sensitive freshness evaluation index.
本研究旨在揭示线粒体在指示冷储和硬化过程中太平洋牡蛎闭壳肌新鲜度变化中的作用。闭壳肌在冷储 96 小时后变硬，并在 6 小时内达到最大硬化程度。在本研究中，在硬化（102 小时）后，肌纤维结构明显断裂和卷曲，在 150 小时时肌节结构消失。在硬化（102 小时）后，线粒体形态发生变化，包括肿胀、嵴断裂和膜结构消失。精氨酸磷酸盐含量从最初的 4.618 逐渐下降到 48 小时时的 1.306µmol/g，此后没有进一步明显变化。ATP 含量在 120 小时内从 6.02 下降到 1.07µmol/g。通过荧光法（JC-1）测量线粒体膜电位（Δφ）。根据添加 ADP 和 CCCP 后闭壳肌中线粒体的 Δφ 差异，将新鲜度变化分为三类。从 0 到 6 小时，线粒体功能完整；从 6 到 48 小时，线粒体功能开始下降；48 小时后，线粒体功能完全消失。结果表明，与其他指标相比，线粒体膜电位更能敏感地反映闭壳肌冷储硬化过程中新鲜度的变化。实际应用：解释死后能量代谢对于控制太平洋牡蛎肌肉质量非常重要。基于 ATP 相关化合物开发的 K 值广泛用于评估海鲜的新鲜度。线粒体是细胞能量代谢的主要场所，其结构和活性的变化可以敏感地反映肌肉细胞的质量变化。预计将开发出更敏感的新鲜度评估指标。
