Prakash Shipra, Iturmendi Nerea, Grelard Axelle, Moine Virginie, Dufourc Erick
Institute of Chemistry & Biology of Membranes & Nano-objects, CBMN UMR 5248, CNRS University of Bordeaux, Bordeaux National Institute of Technology, Allée Geoffroy St Hilaire, 33600 Pessac, France.
BioLaffort, 126 Quai De La Souys, 33100 Bordeaux, France.
Food Chem. 2016 May 15;199:229-37. doi: 10.1016/j.foodchem.2015.12.013. Epub 2015 Dec 7.
Stability of wines is of great importance in oenology matters. Quantitative estimation of dark red precipitates formed in Merlot and Cabernet Sauvignon wine from Bordeaux region for vintages 2012 and 2013 was performed during the oak barrel ageing process. Precipitates were obtained by placing wine at -4°C or 4°C for 2-6 days and monitored by periodic sampling during a one-year period. Spectroscopic identification of the main families of components present in the precipitate powder was performed with (13)C solid-state CPMAS NMR and 1D and 2D solution NMR of partially water re-solubilized precipitates. The study revealed that the amount of precipitate obtained is dependent on vintage, temperature and grape variety. Major components identified include potassium bitartrate, polyphenols, polysaccharides, organic acids and free amino acids. No evidence was found for the presence of proteins. The influence of main compounds found in the precipitates is discussed in relation to wine stability.
葡萄酒的稳定性在酿酒学中至关重要。对2012年和2013年份波尔多地区的梅洛和赤霞珠葡萄酒在橡木桶陈酿过程中形成的深红色沉淀物进行了定量评估。通过将葡萄酒置于-4°C或4°C下2至6天来获得沉淀物，并在一年期间通过定期取样进行监测。使用（13）C固态CPMAS NMR以及部分重新溶解于水的沉淀物的一维和二维溶液NMR对沉淀物粉末中存在的主要成分家族进行光谱鉴定。研究表明，获得的沉淀物量取决于年份、温度和葡萄品种。鉴定出的主要成分包括酒石酸氢钾、多酚、多糖、有机酸和游离氨基酸。未发现存在蛋白质的证据。讨论了沉淀物中发现的主要化合物对葡萄酒稳定性的影响。
