通过基胺酸对安托素在酸性至基本性水溶液中的可逆和不可逆性过程中的化作用的影响
Peiqing Yang1,2, Nuno Basílio2, Xiaojun Liao1
1National Engineering Research Center for Fruit & Vegetable Processing, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory for Food Non-Thermal Processing, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Journal of agricultural and food chemistry
|November 6, 2024
概括
乙化对诸如氨二甲化物之类的氨酸具有影响其稳定性和颜色的作用. 它改变了pH平衡,减缓了降解,并通过π-堆叠相互作用防止不良反应来增强颜色.
科学领域:
- 安托西亚尼的化学成分
- 自然产品的降解,自然产品的退化.
- 谱光测量和运动学
背景情况:
- 氨酸是天然的颜料,在植物中负责红色,紫色和蓝色.
- 它们的稳定性和颜色高度依赖于pH值和分子结构.
- 乙化是一种修饰,可以改变安托素的特性.
研究的目的:
- 调查整个pH范围内的乙化和非乙化安氨酸的热力学和动力学过程.
- 阐明乙化在安东稳定性和降解途径中的作用.
- 通过安东基亚尼丁-酸 π 堆叠来了解分子内共颜色的机制.
主要方法:
- 频谱光度分析涵盖了整个pH频谱.
- 动力学研究使用停止流技术来监测快速反应.
- 对可逆和不可逆降解过程的热力学分析.
主要成果:
- 乙化将平衡转移到有色的基,并扩大了酸的pH域.
- 乙基化适度降低了分体化和异体化速率.
- 基本介质的降解涉及不同的阶段,包括基和氧化添加物的形成,其次是可逆的形形成和不可逆的降解,而乙化防止了初始的短暂状态.
结论:
- 乙化通过调节pH依赖平衡和反应动力学,显著提高了酸的稳定性.
- 通过安托西亚尼丁-酸 π-堆积相互作用的内分子共颜色是提高稳定性的关键机制.
- 了解这些过程对于涉及氨酸作为天然色素的应用至关重要.
相关概念视频
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