Gansu Key Laboratory of Viticulture and Enology, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China.
College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
Food Chem. 2020 May 30;313:126163. doi: 10.1016/j.foodchem.2020.126163. Epub 2020 Jan 7.
The copigmentation effects of polyphenol with different structures vary greatly. Therefore, the aim of this study is to investigate possible interactions in red wine model solutions between oenin and three phenolic compounds: danshensu, caffeic acid and rosmarinic acid. Our results show that the copigmentation of rosmarinic acid is the strongest among the compounds tested. The colourimetric parameters indicate that colour intensity becomes enhanced with increasing concentration of these copigments, leading to darker and more vivid bluish colours. Thermodynamic and quantum chemical investigations are performed to interpret the absorption properties in the visible range. Fluorescence spectroscopy confirms the interaction between caffeic acid and oenin, while FTIR spectroscopic results further suggest a role for hydrogen bonds in the overall process. To our knowledge, this is the first experimentally corroborated direct evidence of hydrogen bonds in copigmentation.
多酚的共沉淀效应因结构的不同而有很大差异。因此，本研究的目的是研究丹酚酸、咖啡酸和迷迭香酸这三种酚类化合物与 oenin 在红葡萄酒模型溶液中可能存在的相互作用。结果表明，在所测试的化合物中，迷迭香酸的共沉淀效应最强。色度参数表明，随着这些共沉淀剂浓度的增加，颜色强度增强，导致颜色更深、更生动的蓝色。热力学和量子化学研究用于解释可见光范围内的吸收特性。荧光光谱证实了咖啡酸与 oenin 之间的相互作用，而傅里叶变换红外光谱（FTIR）的结果进一步表明氢键在整个过程中起作用。据我们所知，这是首次通过实验证实氢键在共沉淀中的直接证据。
