Application of nitrogen forms such as nitrate, urea, and amino acids effects on leaf and berry physiology and wine quality

The Txakoli, a white wine produced in the Basque Country (North of Spain), has recently gained popularity due to wine quality improvement and increase in both acreages of production and wine consumption. The aim of this study was to characterize the chemical and microbiological differences between Txakoli wines made with grapes from different sites.

The quality of wines has often been associated with their geographical area of production. The aim of this work was to characterize Protected Designation of Origin (PDO) Xinomavro red wines from different geographical areas of Amyndeon and Naoussa in Northern Greece, elaborated with variables that contribute to their differentiation, such as soil characteristics, altitude, monthly average temperature and rainfall.
Xinomavro fruit parcels from different vineyards within the two PDO zones (5 PDO Naoussa and 6 PDO Amyndeon) were vinified following a standard winemaking process. A total of 25 aroma compounds were quantified using gas chromatography-mass spectrometry (GC-MS) with simultaneous full scan and selected ion monitoring for data recording, and odor activity values (OAVs) were determined.

Enological tannins are a diversified group of winemaking products that vary in several aspects such as chemical composition, botanical origin, and production method. In consideration of their richness in phenolic compounds, one of their main application in vinification is related to their antioxidant capacity, in particular their ability to consume oxygen during red wine maturation.

Having the possibility to use a wide spectrum of elecromagnetic waves, dielectric spectroscopy is a technique commonly used for electrical characterization of dielectrics or that of materials with high energy storage capacity, just to name a few. Based on the electrical excitation of dipoles (polymer chains or molecules) or ions in relation to the characteristics of a weak external electric field, this method allows the measurement of the complex permittivity or impedance of polarizable materials, each component having a characteristic dipole moment.In recent years, the food industry has also benefited from the potential offered by this technique, whether for the evaluation of fruit quality or during the pasteurization of apple juice [1-3]. As the tests are fast and do not destroy the products, dielectric spectroscopy proved to be an experimental tool suitable for online measurements as well as long-term monitoring.

The analysis of polyfunctional thiols in wine is challenging due to their low abundance and instability within a complex matrix. However, volatile thiols are highly aroma-active, making their accurate quantification in wine at low concentrations crucial [1].