During wine ageing, tannins could react with sulfur dioxide to form sulfonated flavanols which are anticipated to alter tannin binding to proteins contributing to the reduction of astringency during ageing. Previous studies have identified or quantified monomeric and dimeric sulfonated flavanols in aged wines, but the evolution of sulfonated tannins has been lacking. Here, we quantified sulfonated tannins in three Washington state vineyards over a 20-year period, employing targeted LC-QToF analysis. Analysis of 24 wines revealed a systematic trajectory of sulfonated tannins over 20 years. Sulfonated monomers rose consistently with wine age, becoming the dominant form of sulfonated products in all samples at the 20-year mark. Concurrently, there was a decline in native tannins and sulfonated oligomers, suggesting a process of acid-catalyzed depolymerization of native tannins followed by sulfonation via reaction with sulfur dioxide. Future work is needed to understand the stability of sulfonated tannins and their impact on wine astringency.

中文翻译：

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红葡萄酒中磺化单宁随陈酿的演变：一种靶向代谢组学方法


在葡萄酒陈酿过程中，单宁可以与二氧化硫反应形成磺化黄烷醇，预计这些黄烷醇会改变单宁与蛋白质的结合，从而有助于减少陈酿过程中的涩味。以前的研究已经鉴定或量化了陈年葡萄酒中的单体和二聚体磺化黄烷醇，但一直缺乏磺化单宁的进化。在这里，我们采用靶向 LC-QToF 分析，对华盛顿州三个葡萄园在 20 年期间的磺化单宁进行了定量分析。对 24 款葡萄酒的分析揭示了 20 年来磺化单宁的系统轨迹。磺化单体随着葡萄酒的陈酿而持续上升，在 20 年大关成为所有样品中磺化产品的主要形式。同时，天然单宁和磺化低聚物下降，表明天然单宁在酸催化下解聚，然后通过与二氧化硫反应进行磺化反应。需要未来的工作来了解磺化单宁的稳定性及其对葡萄酒涩味的影响。