Abstract:
The copigmentation effect between malvidin-3-O-glucoside and caffeic acid was comprehensive inquiry on the model wine solution, theoretical simulation and real wine. Thermodynamic parameters were determined by UV/Visible spectroscopy and Isothermal titration calorimetry (ITC). Theoretical data were obtained employing a dispersion-corrected density functional approach. The effects in real wines were investigated by adding the caffeic acid during different fermentation periods. Results shown that the copigmentation reaction between caffeic acid and malvidin-3-O-glucoside is a spontaneous exothermic reaction driven by hydrogen bonding and dispersions forces. Computations show that the polyhydroxyl sugar moiety and phenolic hydroxyl groups are the key active sites. The addition of caffeic acid in post-alcohol fermentation samples evidences an improving color characteristics in the wine.
摘要:
综合考察了模型酒溶液中malvidin-3-O-葡萄糖苷与咖啡酸的共色素作用,理论模拟和真实葡萄酒。通过UV/可见光光谱法和等温滴定量热法(ITC)测定热力学参数。使用色散校正的密度泛函方法获得理论数据。通过在不同的发酵时期添加咖啡酸,研究了在实际葡萄酒中的效果。结果表明,咖啡酸和malvidin-3-O-葡萄糖苷之间的共色素反应是由氢键和分散力驱动的自发放热反应。计算显示多羟基糖部分和酚羟基是关键活性位点。在后酒精发酵样品中添加咖啡酸证明了葡萄酒的颜色特性的改善。