The reactivity of malvidin-3-O-glucoside with acetaldehyde, pyruvic and p-coumaric acids, was separately studied in wine model solution in the presence and absence of catechin, by UV–Visible spectrophotometry, NMR and Mass spectrometry. These naturally occurring metabolites were selected on account of their role in determining the red wine color. The scientific bases underlying the wine color are far from being fully clarified. Nonetheless, understanding the factors that govern the wine color is a crucial prerequisite for winemakers to implement appropriate technological practices to produce naturally stable high-quality wines. Among the investigated wine metabolites, acetaldehyde turned out to be the most reactive towards malvidin-3-O-glucoside by forming, as major products, ethylene-linked polymeric pigments that affected chromatic properties of the wine-like model solutions. Pyruvic acid and p-coumaric acid did not react with malvidin-3-O-glucoside, but in combination with catechin, they both determined a significant hypsochromic effect. Unexpectedly, in our model solutions, the formation of pyranoanthocyanins was not observed.

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对葡萄酒颜色演变和稳定性的化学基础的新见解：乙醛的关键作用

在有和没有儿茶素存在的情况下，通过紫外可见分光光度法，NMR和质谱，分别在酒模型溶液中研究了malvidin-3- O-葡萄糖苷与乙醛，丙酮酸和对香豆酸的反应性。选择这些天然存在的代谢物是因为它们在确定红酒颜色中的作用。葡萄酒颜色的科学依据远未得到充分阐明。但是，了解决定葡萄酒颜色的因素对于酿酒师实施适当的技术实践以生产出自然稳定的高品质葡萄酒至关重要。在所研究的葡萄酒代谢产物中，乙醛对malvidin-3- O的反应活性最高。-葡糖苷，通过形成影响酒样模型溶液色度特性的乙烯连接聚合物颜料作为主要产品。丙酮酸和对香豆酸不与malvidin-3- O-葡萄糖苷反应，但与儿茶素联合使用时，它们均确定了显着的七色变色作用。出乎意料的是，在我们的模型溶液中，未观察到吡喃花色素的形成。