电子偏磁共振 (EPR) 旋转陷应用于查多内葡萄酒:醇含量和乙醇的影响
Pei Han1,2, Alexandre Pons1,2,3
1Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, Villenave d'Ornon, F-33140, France.
Current research in food science
|January 14, 2026
概括
化学氧化会通过激进反应在老化过程中损害白葡萄酒. 电子偏磁共振 (EPR) 可以监测1-基乙基 (1-HER) 的形成,有助于评估葡萄酒的老化潜力.
科学领域:
- 食品化学 食品化学
- 葡萄酒化学 葡萄酒化学
- 氧化化学 有氧化化学
背景情况:
- 由芬顿类反应驱动的化学氧化,在白酒瓶老化过程中会造成重大损害.
- 这一过程从乙醇中产生1-基乙基 (1-HER),影响葡萄酒的质量.
研究的目的:
- 优化和验证使用电子偏磁共振 (EPR) 研究1-HER形成动力学的方法.
- 调查影响1-HER动态的因素及其与葡萄酒老化潜力的关系.
主要方法:
- 采用了优化的EPR方法,采用芬顿反应和特定的旋转陷 (N-tert-Butyl-α-(4-pyridyl-1-oxide) )
- 关键反应参数 (温度,溶解氧,自由双硫酸盐) 被优化,并评估了乙甲的作用.
- 一个日志正常模型被验证来描述1-HER形成/降解动力学.
主要成果:
- 优化的EPR协议,考虑到乙甲对二硫酸盐的影响,适合常规分析.
- 这项研究成功地根据1-HER形成动力学对69种查多内葡萄酒进行了排名.
- 低酸含量,特别是酸,与缓慢,高的1-HER生产相关.
- 乙醇度显著影响了1-HER的动力学,但不是在典型的白葡萄酒范围内 (12-15%体积). ) 的情况.
结论:
- 基于EPR的激素氧化反应监测为评估白葡萄酒老化潜力提供了一个有前途的方法.
- 葡萄酒的成熟度和酸概况可能会调节1-HER形成动力学,从而影响沙多内葡萄酒的老化特征.
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