Centro Tecnológico de la Vid y el Vino, Facultad de Ciencias Agrarias, Universidad de Talca, Av. Lircay S/N, Talca, Chile; Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja-CSIC-Universidad de La Rioja), Carretera de Burgos Km. 6, Finca La Grajera, 26007 Logroño, Spain.
Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja-CSIC-Universidad de La Rioja), Carretera de Burgos Km. 6, Finca La Grajera, 26007 Logroño, Spain.
Food Res Int. 2017 Jun;96:46-53. doi: 10.1016/j.foodres.2017.03.025. Epub 2017 Mar 12.
Wine quality greatly depends on its chemical composition. Among the most important wine chemical compounds, flavonoids are the major contributors to wine organoleptic properties while amino acids have a huge impact on fermentation development and wine volatile profile. Likewise, nitrogen applications are known to have an impact on wine composition. Therefore, the aim of this work was to study the effects of foliar nitrogen applications on wine flavonoid and amino acid composition. The experiment involved five foliar nitrogen applications at veraison time: urea (Ur), urea plus sulphur (Ur+S), arginine (Arg), and two commercial fertilizers Nutrimyr Thiols (NT) and Basfoliar Algae (BA). The results showed that nitrogen foliar treatments decreased wine flavonoid content although the effect varied according to each treatment. This could be related to a low vine nitrogen requirement, since must yeast assimilable nitrogen (YAN) was above acceptable threshold values for all samples. With regard to wine amino acid content, all treatments except for Ur increased its values after the applications. Finally, foliar nitrogen treatments greatly influenced wine composition. Among them, urea seemed to exert the most negative effect on both phenolics and amino acids. In addition, an inverse relationship between wine amino acid content and flavonol concentration was exhibited.
葡萄酒的质量在很大程度上取决于其化学成分。在最重要的葡萄酒化学化合物中，类黄酮是影响葡萄酒感官特性的主要因素，而氨基酸对发酵发展和葡萄酒挥发性成分有巨大影响。同样，氮的应用也被认为会影响葡萄酒的成分。因此，本研究的目的是研究叶面施氮对葡萄酒类黄酮和氨基酸组成的影响。该实验在葡萄转色期进行了五次叶面氮处理：尿素（Ur）、尿素加硫（Ur+S）、精氨酸（Arg），以及两种商业肥料 Nutrimyr 硫醇（NT）和 Basfoliar 藻类（BA）。结果表明，氮叶面处理降低了葡萄酒类黄酮的含量，尽管每种处理的效果不同。这可能与葡萄对氮的需求较低有关，因为所有样品的酵母可同化氮（YAN）都高于可接受的阈值。关于葡萄酒氨基酸含量，除了 Ur 之外，所有处理在应用后都增加了其含量。最后，叶面氮处理对葡萄酒的组成有很大的影响。其中，尿素似乎对酚类物质和氨基酸都有最负面的影响。此外，还表现出葡萄酒氨基酸含量与黄酮醇浓度之间的反比关系。
