Controlled formation of emulsion gels stabilized by salted myofibrillar protein under malondialdehyde (MDA)-induced oxidative stress.
Controlled formation of emulsion gels stabilized by salted myofibrillar protein under malondialdehyde (MDA)-induced oxidative stress.
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DOI：
10.1021/jf505916f
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发表时间：
2015-04
影响因子：
6.1
通讯作者：
Feibai Zhou;Weizheng Sun;Mouming Zhao
中科院分区：
文献类型：
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作者：
Feibai Zhou;Weizheng Sun;Mouming Zhao
本研究提出了在丙二醛 (MDA) 产生的氧化应激下，盐化肌原纤维蛋白 (MP) 稳定乳液的冷凝固凝胶化。比较了一系列 MDA/NaCl 浓度下的凝胶特性，包括凝胶粘弹性、强度、保水能力 (WHC)、截留的蛋白质量和微观结构。进一步测定和比较了由脂质氢过氧化物指示的乳液凝胶的氧化稳定性。结果表明，一定离子强度（0.2-0.6 M）下MP稳定溶胀状态的乳液是MDA下形成凝胶的前提。在中间 MDA 浓度 (2.5-10 mM) 存在下，乳液凝胶显示出改善的弹性、强度、WHC 和氧化稳定性。这种改进主要归因于通过 MDA 增强的蛋白质-蛋白质交联，这些交联在吸收和/或未吸收的蛋白质之间均匀形成，从而在网络内捕获更多数量和部分的蛋白质。因此，油滴更好地粘附在凝胶基质上。然而，添加高浓度 MDA (25-50 mM) 会导致形成过多的共价键，这可能会破坏蛋白质-蛋白质键并引发蛋白质从界面解吸。这最终导致“漏油”现象以及凝胶结构的崩溃，从而总体上降低了凝胶性能和氧化稳定性。
This study presented the cold-set gelation of emulsions stabilized by salted myofibrillar protein (MP) under oxidative stress originated from malondialdehyde (MDA). Gel properties were compared over a range of MDA/NaCl concentrations including gel viscoelastic properties, strength, water-holding capacity (WHC), amount of protein entrapped, and microstructure. The oxidative stability of emulsion gels as indicated by lipid hydroperoxide was further determined and compared. Results indicated that emulsion stabilized by MP at swollen state under certain ionic strengths (0.2-0.6 M) was the premise of gel formation under MDA. In the presence of intermediate MDA concentrations (2.5-10 mM), the emulsion gels showed an improved elasticity, strength, WHC, and oxidative stability. This improvement should be mainly attributed to the enhanced protein-protein cross-linkings via MDA, which were homogeneously formed among absorbed and/or unabsorbed proteins, entrapping a greater amount and fractions of protein within network. Therefore, the oil droplets were better adherent to the gel matrix. Nevertheless, addition of high MDA concentrations (25-50 mM) led to the formation of excessive covalent bonds, which might break protein-protein bonds and trigger the desorption of protein from the interface. This ultimately caused "oil leak" phenomena as well as the collapse of gel structure and, thus, overall decreased gel properties and oxidative stability.