LEAF-Linking Landscape, Environment, Agriculture and Food Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal.
CENSE-Center for Environmental and Sustainability Research, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal.
Molecules. 2021 Oct 14;26(20):6188. doi: 10.3390/molecules26206188.
Protein haze in white wine is one of the most common non-microbial defects of commercial wines, with bentonite being the main solution utilized by the winemaking industry to tackle this problem. Bentonite presents some serious disadvantages, and several alternatives have been proposed. Here, an alternative based on a new cellulose derivative (dicarboxymethyl cellulose, DCMC) is proposed. To determine the efficiency of DCMC as a bentonite alternative, three monovarietal wines were characterized, and their protein instability and content determined by a heat stability test (HST) and the Bradford method, respectively. The wines were treated with DCMC to achieve stable wines, as shown by the HST, and the efficacy of the treatments was assessed by determining, before and after treatment, the wine content in protein, phenolic compounds, sodium, calcium, and volatile organic compounds (VOCs) as well as the wine pH. DCMC applied at dosages such as those commonly employed for bentonite was able to reduce the protein content in all tested wines and to stabilize all but the Moscatel de Setúbal varietal wine. In general, DCMC was shown to induce lower changes in the wine pH and phenolic content than bentonite, reducing the wine calcium content. Regarding which VOCs are concerned, DCMC produced a general impact similar to that of bentonite, with differences depending on wine variety. The results obtained suggest that DCMC can be a sustainable alternative to bentonite in protein white wine stabilization.
白葡萄酒中的蛋白浑浊是商业葡萄酒中最常见的非微生物缺陷之一，膨润土是酿酒行业解决这个问题的主要方法。膨润土存在一些严重的缺点，因此已经提出了几种替代方法。在这里，提出了一种基于新型纤维素衍生物（二羧甲基纤维素，DCMC）的替代方法。为了确定 DCMC 作为膨润土替代物的效率，对三种单品种葡萄酒进行了表征，并分别通过热稳定性测试（HST）和 Bradford 法测定其蛋白质不稳定性和含量。用 DCMC 处理葡萄酒以实现 HST 稳定的葡萄酒，并通过测定处理前后葡萄酒中的蛋白质、酚类化合物、钠、钙和挥发性有机化合物（VOCs）以及葡萄酒 pH 值来评估处理的效果。DCMC 的用量与膨润土常用的用量相当，能够降低所有测试葡萄酒中的蛋白质含量，并稳定除 Moscatel de Setúbal 品种葡萄酒以外的所有葡萄酒。总的来说，DCMC 对葡萄酒 pH 值和酚类含量的影响低于膨润土，降低了葡萄酒中的钙含量。就 VOCs 而言，DCMC 产生的影响与膨润土相似，只是因葡萄酒品种而异。研究结果表明，DCMC 可以作为稳定蛋白白葡萄酒的膨润土的可持续替代品。
