National Wine and Grape Industry Centre, Mambarra Drive, Wagga Wagga, NSW 2678, Australia; School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
Australian Wine Research Institute, Glen Osmond, SA 5064, Australia.
Food Res Int. 2017 Aug;98:95-102. doi: 10.1016/j.foodres.2016.11.017. Epub 2016 Nov 19.
A variety of techniques have been developed with the ability to measure different forms of metals in wine with the ultimate aim of providing a more accurate indicator of metal induced spoilage of wine. This study was conducted in order to identify which wine components influence the measurement of Cu and Fe in their fractionated and/or electrochemically active forms. The measurement techniques involved detection of labile Cu by stripping potentiometry and fractionation of Cu and Fe by sequential solid phase extraction, with detection by inductively coupled plasma-optical emission spectroscopy. The wine components assessed included those extracted from wine (red wine tannin, white wine protein, white wine polysaccharide, red wine polyphenol, white wine polyphenol), and commercially available monomeric compounds, including phenolic compounds and sulfur-containing compounds. For Cu, only hydrogen sulfide, which is known to induce the formation of Cu(I) sulfide, showed any appreciable influence on the fractionation and electrochemical detection of Cu. This form of Cu was also identified as the major component of red and white wines. For Fe, the fractionation was different for red versus white wine, and influenced significantly by extracted red wine polyphenol, (-)-epicatechin, gallic acid and tartaric acid. The wine components showed more influence on Fe at pH4.00 compared to pH3.25. These results enable a targeted use of these techniques in the assessment of metal-induced spoilage of wine.
已经开发出了多种技术，能够测量葡萄酒中不同形式的金属，最终目的是提供更准确的金属诱导葡萄酒变质的指标。本研究旨在确定哪些葡萄酒成分影响 Cu 和 Fe 的分馏和/或电化学活性形式的测量。所涉及的测量技术包括通过剥离电位法检测不稳定的 Cu，以及通过顺序固相萃取对 Cu 和 Fe 进行分馏，并用电感耦合等离子体 - 光学发射光谱法进行检测。评估的葡萄酒成分包括从葡萄酒中提取的成分（红葡萄酒单宁、白葡萄酒蛋白质、白葡萄酒多糖、红葡萄酒多酚、白葡萄酒多酚）和市售的单体化合物，包括酚类化合物和含硫化合物。对于 Cu，只有已知会诱导 Cu(I)硫化物形成的硫化氢对 Cu 的分馏和电化学检测表现出任何明显的影响。这种形式的 Cu 也被确定为红葡萄酒和白葡萄酒的主要成分。对于 Fe，红葡萄酒与白葡萄酒的分馏方式不同，并且受提取的红葡萄酒多酚、(-)-表儿茶素、没食子酸和酒石酸的显著影响。与 pH3.25 相比，葡萄酒成分在 pH4.00 时对 Fe 的影响更大。这些结果使这些技术能够在评估金属诱导葡萄酒变质方面得到有针对性的应用。
