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Updated: Jun 27, 2025

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14C-同位素用于量化香料化合物和β-乳球蛋白之间的共价反应

Igor Shepelev¹, Gary A Reineccius¹

¹Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Avenue, St. Paul, Minnesota 55108, United States.

Journal of agricultural and food chemistry

|April 29, 2024

概括

这项研究研究了beta-lactoglobulin和风味化合物之间的共价键. 2-乙异硫酸显示出最高的反应性,表明显著的蛋白质-风味相互作用.

科学领域:

食品化学食品化学
蛋白质化学蛋白质化学
化学动力学化学动力学

背景情况:

了解风味蛋白相互作用对于食品产品开发至关重要.
共价键的形成可以改变风味感知和蛋白质的功能.
β-乳糖球蛋白是一种常见的食物蛋白质,易受化学修饰.

研究的目的:

量化β-乳糖球蛋白与模型风味化合物之间的共价反应的速率和程度.
为了比较不同功能组 (,,异酸盐) 与蛋白质的活性.
评估温度对这些反应动力学的影响.

主要方法:

使用14C标记方法来追踪味道化合物的纳入β-乳糖球蛋白.
在25°C,45°C和65°C下为期28天,用标记的风味化合物 (UDO,DAL,PEITC) 化蛋白质溶液.
在多个时间点 (1,3,7,14,21,28天) 监测反应进展.

主要成果:

2-phenylethyl isothiocyanate (PEITC) 的反应性最高 (反应率高达71.8%),其次是decanal (DAL,高达16.4%) 和2-undecanone (UDO,高达0.9%).
所有化合物的反应率最初都很快,大约在7天后显著放缓.
高温,特别是65°C,加速了PEITC的反应速度和结合程度.

结论:

香味化合物与β-乳糖球蛋白的反应性因其化学结构而异.
异基亚酸盐对β-乳糖球蛋白具有高度反应性,这表明在食品系统中可能存在显著的共价变异.
温度在风味蛋白共价相互作用的动力学和程度上起着至关重要的作用,PEITC在高温下可能会和反应部位.

关键词:

2 - 乙烯基异硫酸酸.这是一种2-undecanone.同价键是一种共价键.十道式的十道式的豆蛋白分离物豆蛋白分离物

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