海参低温嫩化过程中体壁胶原组织的微观结构变化及机理

加热熟化是即食海参加工的关键步骤。申请人所在课题组建立了低温嫩化技术，采用此技术处理的海参熟化后体壁嫩度好于直接熟化的海参。嫩化技术是肉制品加工的常用技术，其机理是内源蛋白酶对肌肉组织的有限降解。与肉制品不同，海参体壁主要由易变胶原组织（mutable connective tissue, MCT）构成。课题组前期研究表明，海参体壁组织蛋白酶L在低温嫩化过程中活性增强，同时海参胶原原纤维周期性横纹结构消失。据此课题组推测，海参体壁低温嫩化的实质是内源酶系对MCT的有限降解。本项目拟通过研究海参体壁MCT微观结构在低温嫩化过程中的变化及各内源酶系在MCT微观结构变化中发挥的作用，揭示低温嫩化机理。为了实现预期目标，课题组将研究海参经低温嫩化处理后体壁MCT微观结构变化及溶出成分变化；研究内源酶被抑制的海参经低温嫩化处理后体壁的嫩化效果。通过本研究，也可为其他海洋动物的低温嫩化技术提供依据。

Thermal ripening is key processing step in production of ready-to-eat sea cucumber. Our research team has developed a low-temperature tenderization technology. After the tenderization processing, sea cucumber was rapidly processed by a high-temperature ripening step, and its tenderness was better than the one without low-temperature tenderization processing. Tenderization is a common technology in meat processing. It was reported that the nature for tenderization of meat is a limited hydrolysis of muscle tissue by endogenous proteases. In contrast with meat, sea cucumber body wall is mainly mutable connective tissue (MCT). Our previous studies indicated that the activity of cathepsin L in sea cucumber body wall was activated during low-temperature tenderization processing. Meanwhile, the periodic cross striation of fibril disappeared. In such cases, our research team speculated that the nature of low-temperature tenderization of sea cucumber body wall is limited degradation of MCT caused by endogenous proteases. The main purpose of this project is to reveal the mechanism of low-temperature tenderization of sea cucumber body wall though investigation of microstructural changes of MCT and the roles of endogenous proteases in the changes. To achieve the goal, our team intend to study the microstructural changes of MCT of sea cucumber body wall during low-temperature tenderization; our team intend to study the soluble components of MCT of sea cucumber body wall during low-temperature tenderization; our team intend to study the effects of inhibition of endogenous proteases on low-temperature tenderization of sea cucumber body wall by in situ perfusion technology. The present study also can provide evidence for low-temperature tenderization of other sea animals.