Escuela Universitaria de Ingeniería Técnica Agrícola, Universidad de Castilla-La Mancha, Ronda de Calatrava 7, 13071 Ciudad Real, Spain.
J Agric Food Chem. 2011 Sep 14;59(17):9523-31. doi: 10.1021/jf201546j. Epub 2011 Aug 17.
Formation of wine pyranoanthocyanins in model wine was monitored by HPLC-DAD-ESI-MS/MS, using red grape skin extracts and wine fermentation metabolites (acetaldehyde, pyruvic and acetoacetic acids, and diacetyl) and also hydroxycinnamic acids (p-coumaric, caffeic, ferulic, and sinapic acids). Pyruvic acid and acetaldehyde reacted fast, the first reaching high product yield and the second inducing mainly pigment polymerization. In contrast, acetoacetic acid and diacetyl reacted slowly with poor product yields. Hydroxycinnamic acids progressively reacted without apparent formation of polymeric pigments, the reaction rate and yield increasing as the number of hydroxy/methoxy groups did. Substituent at C-10 strongly affected the visible maximum absorbance wavelength, whereas B-ring substitution pattern or sugar acylation exerted little effect. The 10-methylpyranoanthocyanins formed from acetoacetic acid were also found as side products in the formation of 10-carboxypyranoanthocyanins. Finally, we report for the first time on UV-vis and MS spectral data of 10-acetylpyranoanthocyanins formed from diacetyl, and their occurrence in commercial red wines is suggested.
采用高效液相色谱-二极管阵列检测-电喷雾串联质谱（HPLC-DAD-ESI-MS/MS）监测模型酒中葡萄酒吡喃并花青素的形成，使用红葡萄皮提取物和葡萄酒发酵代谢产物（乙醛、丙酮酸和乙酰乙酸以及双乙酰）以及羟基肉桂酸（对香豆酸、咖啡酸、阿魏酸和芥子酸）。丙酮酸和乙醛反应迅速，前者达到高产物产率，后者主要诱导色素聚合。相比之下，乙酰乙酸和双乙酰反应缓慢，产物产率低。羟基肉桂酸逐渐反应，没有明显形成聚合色素，反应速率和产率随羟基/甲氧基数量的增加而增加。C-10 上取代基强烈影响可见最大吸收波长，而 B 环取代模式或糖酰化作用影响很小。还发现从乙酰乙酸形成的 10-甲基吡喃并花青素也是 10-羧基吡喃并花青素形成的副产物。最后，我们首次报道了双乙酰形成的 10-乙酰基吡喃并花青素的紫外可见和质谱光谱数据，并提出了它们在商业红葡萄酒中的存在。
