在加热的蛋黄中探索非平衡过程和时空缩放规律,使用连贯的X射线
Nimmi Das Anthuparambil1,2, Anita Girelli3, Sonja Timmermann4
1Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany. nimmi.das.anthuparambil@desy.de.
Nature communications
|September 11, 2023
概括
蛋黄通过蛋白质凝和低密度脂蛋白 (LDL) 聚合产生柔软,颗粒状的质地. 温度会影响这些过程,75°C左右的值会影响凝的动态.
科学领域:
- 食品科学和生物物理
- 研究食品微观结构的物理化学.
背景情况:
- 蛋黄的独特质地源于加热过程中的复杂的蛋白质-脂质相互作用.
- 了解蛋黄成分在微观结构发展中的特定作用对于食品加工至关重要.
研究的目的:
- 阐明蛋白质,低密度脂蛋白 (LDL) 和蛋黄颗粒对煮熟蛋黄的粒状凝微结构和微观动态的功能性贡献.
- 确定温度如何影响这些成分的贡献.
主要方法:
- 利用X射线光子相关谱学 (XPCS) 来探测微观动力学.
- 分析了蛋白质凝和LDL聚合在微观结构形成中的作用.
- 研究了蛋白质和LDL聚合动力学的时间-温度叠加 (TTS) 原理.
主要成果:
- 蛋黄的粘度主要由蛋白质凝决定.
- 粒状凝微结构是由LDL聚合的程度控制的.
- 蛋白质变性-聚合-凝和LDL聚合都遵循阿雷尼乌斯类型的TTS,表明共享的温度依赖机制.
- 在75°C以上,TTS分解,揭示了温度独立的凝动态.
结论:
- 蛋白质凝决定了粘度,而LDL聚合则决定了煮熟的蛋黄的粒状质地.
- 过程涉及蛋白质和LDL的非平衡动态,临界温度值影响反应速率.
- 这项研究提供了关于通过精确的温度和时间管理在食品加工中控制蛋黄微观结构的见解.
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