Sciences pour l'Œnologie (SPO), Institut National de Recherche en Agriculture, Alimentation et Environnement (INRAE), Université de Montpellier, Montpellier SupAgro, 34060 Montpellier, France.
Institut Français de la Vigne et du Vin, 30240 Le Grau-du-Roi, France.
J Agric Food Chem. 2020 Nov 25;68(47):13450-13458. doi: 10.1021/acs.jafc.0c00094. Epub 2020 Mar 17.
Bentonite fining is the most popular treatment used to remove proteins in white and rosé wines. The usual heat test used to adjust the bentonite dose consists of heating the wine during 30 min at 80 °C. At this temperature, all of the proteins are unfolded, and this can lead to an overestimation of the dose. We have shown that proteins adsorb on bentonite in a specific order and, more importantly, that the proteins responsible for haze formation adsorb first. Fluorescence spectroscopy showed that this is due to the structural properties of proteins, which can be classified as hard and soft proteins. Alternative heat tests were performed at a lower temperature (40 °C) and showed a better correlation with accelerated aging. These tests were also less dependent upon the wine pH.
膨润土澄清是最常用的处理方法，用于去除白葡萄酒和桃红葡萄酒中的蛋白质。通常用于调整膨润土剂量的热试验包括在 80°C 下加热葡萄酒 30 分钟。在这个温度下，所有的蛋白质都展开了，这可能会导致剂量的高估。我们已经表明，蛋白质在膨润土上以特定的顺序吸附，更重要的是，导致浑浊形成的蛋白质首先吸附。荧光光谱表明，这是由于蛋白质的结构特性，可以将其分类为硬蛋白和软蛋白。在较低温度（40°C）下进行了替代热试验，与加速老化的相关性更好。这些测试也较少依赖于葡萄酒的 pH 值。
