Grupo de Investigación en Polifenoles (GIP), Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain.
Anal Chim Acta. 2010 Feb 15;660(1-2):171-6. doi: 10.1016/j.aca.2009.10.020. Epub 2009 Oct 17.
During maturation and ageing in oak barrels wines improve their organoleptic properties. Ellagitannins can be released from wood to the wine and be involved in oxidation reactions and seem to influence the astringency and colour properties of the wine. Nevertheless, the ellagitannins levels are lower than those of other wine constituents and, consequently, they are not easily detected. This study has developed a two-step fractionation method consisting of a solid phase extraction in C-18 Sep-Pak cartridges followed by size exclusion chromatography in hand-packed Sephadex LH-20 minicolumn for the detection of oak ellagitannins in different types of wines. An HPLC method has also been developed which allows the separation of compounds with the same m/z ratios, facilitating the ellagitannin identification by means of the mass spectrometric analyses. The main oak ellagitannins (grandinin, vescalagin, roburin E and castalagin) were isolated, detected separately and identified in a spiked wine and in three real ones, proving the usefulness of the fractionation method.
在橡木桶中成熟和陈酿过程中，葡萄酒的感官特性得到改善。鞣花单宁可以从木材中释放到葡萄酒中，并参与氧化反应，似乎影响葡萄酒的涩味和颜色特性。然而，鞣花单宁的水平低于其他葡萄酒成分，因此不容易检测到。本研究开发了一种两步分级方法，包括 C-18 Sep-Pak 小柱上的固相萃取，然后在手填 Sephadex LH-20 微柱上进行尺寸排阻色谱，用于检测不同类型葡萄酒中的橡木鞣花单宁。还开发了一种 HPLC 方法，该方法允许分离具有相同 m/z 比值的化合物，通过质谱分析有助于鞣花单宁的鉴定。在添加了鞣花单宁的葡萄酒和三种实际葡萄酒中，分别分离、检测并鉴定了主要的橡木鞣花单宁（鞣花丹宁、栗木鞣花丹宁、罗布鞣花丹宁 E 和诃子鞣花丹宁），证明了分级方法的有用性。
