Jaeckels Nadine, Meier Miriam, Dietrich Helmut, Will Frank, Decker Heinz, Fronk Petra
Institute for Molecular Biophysics, Johannes Gutenberg-University Mainz, Jakob Welder Weg 26, 55128 Mainz, Germany.
Institute of Wine Analysis and Beverage Research, Geisenheim University, Von-Lade-Str. 1, 65366 Geisenheim, Germany.
Food Chem. 2016 Jun 1;200:38-45. doi: 10.1016/j.foodchem.2015.12.088. Epub 2015 Dec 24.
Polysaccharides are the major high-molecular weight components of wines. In contrast, proteins occur only in small amounts in wine, but contribute to haze formation. The detailed mechanism of aggregation of these proteins, especially in combination with other wine components, remains unclear. This study demonstrates the different aggregation behavior between a buffer and a model wine system by dynamic light scattering. Arabinogalactan-protein, for example, shows an increased aggregation in the model wine system, while in the buffer system a reducing effect is observed. Thus, we could show the importance to examine the behavior of wine additives under conditions close to reality, instead of simpler buffer systems. Additional experiments on melting points of wine proteins reveal that only some isoforms of thaumatin-like proteins and chitinases are involved in haze formation. We can confirm interactions between polysaccharides and proteins, but none of these polysaccharides is able to prevent haze in wine.
多糖是葡萄酒中的主要高分子量成分。相比之下，蛋白质在葡萄酒中的含量很少，但会导致酒体浑浊。这些蛋白质聚集的详细机制，尤其是与葡萄酒其他成分结合时的机制，仍不清楚。本研究通过动态光散射证明了缓冲液和模拟葡萄酒体系之间不同的聚集行为。例如，阿拉伯半乳聚糖蛋白在模拟葡萄酒体系中聚集增加，而在缓冲液体系中则观察到减少作用。因此，我们可以看出在接近实际的条件下而非更简单的缓冲液体系中研究葡萄酒添加剂行为的重要性。关于葡萄酒蛋白质熔点的额外实验表明，只有某些类甜蛋白和几丁质酶同工型参与了酒体浑浊的形成。我们可以证实多糖和蛋白质之间存在相互作用，但这些多糖均无法防止葡萄酒出现浑浊。
