Zhu Xueshen, Ma Zhenghao, Zhang Xinyu, Huang Xuefang, Liu Junya, Zhuang Xinbo
Key Lab of Biological Functional Molecules of Jiangsu Province, College of Life Science and Chemistry, Jiangsu Second Normal University, Nanjing 211200, China.
College of Food Science and Engineering, Nanjing University of Finance & Economics, Nanjing 211171, China.
Gels. 2022 Oct 6;8(10):633. doi: 10.3390/gels8100633.
This paper focuses on the effect of malondialdehyde-induced oxidative modification (MiOM) on the gel properties of duck myofibrillar proteins (DMPs). DMPs were first prepared and treated with oxidative modification at different concentrations of malondialdehyde (0, 0.5, 2.5, 5.0, and 10.0 mmol/L). The physicochemical changes (carbonyl content and free thiol content) and gel properties (gel whiteness, gel strength, water holding capacity, rheological properties, and microstructural properties) were then investigated. The results showed that the content of protein carbonyl content increased with increasing MDA oxidation (p < 0.05), while the free thiol content decreased significantly (p < 0.05). Meanwhile, there was a significant decrease in gel whiteness; the gel strength and water-holding capacity of protein gels increased significantly under a low oxidation concentration of MDA (0−5 mmol/L); however, the gel strength decreased under a high oxidation concentration (10 mmol/L) compared with other groups (0.5−5 mmol/L). The storage modulus and loss modulus of oxidized DMPs also increased with increasing concentrations at a low concentration of MDA (0−5 mmol/L); moreover, microstructural analysis confirmed that the gels oxidized at low concentrations (0.5−5 mmol/L) were more compact and homogeneous in terms of pore size compared to the high concentration or blank group. In conclusion, moderate oxidation of malondialdehyde was beneficial to improve the gel properties of duck; however, excessive oxidation was detrimental to the formation of dense structured gels.
本文聚焦于丙二醛诱导的氧化修饰（MiOM）对鸭肌原纤维蛋白（DMPs）凝胶特性的影响。首先制备DMPs，并在不同浓度的丙二醛（0、0.5、2.5、5.0和10.0 mmol/L）下进行氧化修饰处理。随后研究其理化变化（羰基含量和游离巯基含量）及凝胶特性（凝胶白度、凝胶强度、持水能力、流变学特性和微观结构特性）。结果表明，蛋白质羰基含量随丙二醛氧化程度的增加而升高（p < 0.05），而游离巯基含量显著降低（p < 0.05）。同时，凝胶白度显著降低；在低氧化浓度的丙二醛（0−5 mmol/L）下，蛋白质凝胶的凝胶强度和持水能力显著增加；然而，与其他组（0.5−5 mmol/L）相比，在高氧化浓度（10 mmol/L）下凝胶强度降低。在低浓度的丙二醛（0−5 mmol/L）下，氧化DMPs的储能模量和损耗模量也随浓度增加而升高；此外，微观结构分析证实，与高浓度组或空白组相比，低浓度（0.5−5 mmol/L）氧化的凝胶在孔径方面更致密且均匀。总之，丙二醛的适度氧化有利于改善鸭肉的凝胶特性；然而，过度氧化不利于形成致密结构的凝胶。
