Laboratory of Enology and Alcoholic Drinks (LEAD), Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece.
Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece.
J Agric Food Chem. 2023 Feb 15;71(6):2952-2963. doi: 10.1021/acs.jafc.2c07325. Epub 2023 Jan 31.
The concentration of nitrogen in must is critical to yeast fermentation efficiency and wine aroma profile. The present work determined the effect of the amount of yeast assimilable nitrogen (YAN) on fermentation kinetics, aroma production, and gene expression patterns of the wine yeast . Fermentations were performed under two different YAN concentrations of must. Acetate esters, linalool, and nerol appeared to be clearly affected by the different YAN levels. Real-time-PCR results revealed that the genes involved in ethyl and acetate esters production recorded, in general, higher transcript levels under high nitrogen supplementation. In addition, an up-regulation of the and genes, which are related to terpenes production, was observed in the case of high nitrogen content and it is well corresponded to the terpenol concentration found. Our study revealed the impact of nitrogen supplementation on yeast metabolism and its importance to adjust wine's aromatic composition and sensory profile.
葡萄汁中的氮浓度对酵母发酵效率和葡萄酒香气特征有重要影响。本研究旨在确定酵母可同化氮（YAN）的量对葡萄酒酵母发酵动力学、香气产生和基因表达模式的影响。在两种不同的 YAN 浓度下进行发酵。乙酸酯、芳樟醇和橙花醇的产生似乎明显受到不同 YAN 水平的影响。实时 PCR 结果表明，参与乙基和乙酸酯产生的基因在高氮补充下通常具有更高的转录水平。此外，在高氮含量的情况下，观察到与萜烯产生相关的 和 基因的上调，这与萜烯醇浓度的发现很好地对应。本研究揭示了氮补充对酵母代谢的影响及其对调整葡萄酒香气组成和感官特征的重要性。
