The Australian Wine Research Institute, Waite Precinct, Hartley Grove cnr Paratoo Road, Urrbrae (Adelaide) SA 5064, PO Box 197, Glen Osmond, SA 5064, Australia.
The Australian Wine Research Institute, Waite Precinct, Hartley Grove cnr Paratoo Road, Urrbrae (Adelaide) SA 5064, PO Box 197, Glen Osmond, SA 5064, Australia; Wine Australia, P.O. Box 660, Kent Town, SA 5071, Australia.
Food Chem. 2021 Aug 1;352:129343. doi: 10.1016/j.foodchem.2021.129343. Epub 2021 Feb 20.
In this work, the interaction of wine macromolecules with a bovine serum albumin (BSA) was investigated using fluorescence correlation spectroscopy (FCS). FCS offers the opportunity to study molecular and macromolecular aggregation without disturbing the wine by introducing only very small amounts of fluorescently labelled molecules to the system. It was observed that the diffusion coefficient of fluorescently labelled BSA varies with the addition of wine macromolecules, indicating changes in the protein conformation and the formation of complexes and aggregates. The addition of a wine polysaccharide rhamnogalacturonan II-enriched fraction led to aggregation, while addition of a mannoprotein-enriched fraction exhibited a protective effect on protein aggregation. Proteins strongly interacted with tannins, leading to the precipitation of protein-tannin complexes, while the presence of polysaccharides prevented this precipitation. Finally, the application of FCS was demonstrated in real wines, to investigate the problem of protein haze formation through live monitoring of heat-induced aggregation in wine.
在这项工作中，使用荧光相关光谱（FCS）研究了葡萄酒大分子与牛血清白蛋白（BSA）的相互作用。FCS 通过向体系中仅引入少量荧光标记分子，为研究分子和大分子聚集提供了机会，而不会干扰葡萄酒。结果表明，荧光标记 BSA 的扩散系数随葡萄酒大分子的添加而变化，表明蛋白质构象发生变化，并形成复合物和聚集体。添加富含鼠李半乳糖醛酸聚糖 II 的葡萄酒多糖会导致聚集，而添加富含甘露糖蛋白的部分则对蛋白质聚集表现出保护作用。蛋白质与单宁强烈相互作用，导致蛋白质-单宁复合物沉淀，而多糖的存在则阻止了这种沉淀。最后，该方法在实际葡萄酒中得到了应用，通过实时监测葡萄酒中热诱导聚集，研究了蛋白质浑浊形成的问题。
