Soil quality in Beaujolais vineyard. Importance of pedology and cultural practices

Phenolic compounds play a central role in sensory characteristics of wine, such as colour, mouthfeel, flavour and determine its shelf life. Furthermore, the major non-enzymatic wine oxidation process is due to the catalytic oxidation of phenols in quinones. Due their importance, during the years have been developed different analytical methods to monitor the concentration of phenols in wine, such as Folin-Ciocalteu method, spectrophotometric techniques and HPLC. These methods can also be used to follow some oxidation-related chemical transformations.

Ultra High-Pressure Homogenization (UHPH) is a high-pressure pumping at 300 MPa (>200 MPa) with a subsequent depressurization against a highly resistant valve made of tungsten carbide covered by ceramic materials or carbon nanoparticles. The intense impact and shear efforts produce the nano-fragmentation of colloidal biopolymers including the elimination of microorganism (pasteurization or sterilization depending on in-valve temperature) and the inactivation of enzymes.

Foliar application of urea may be an efficient way to alter grape and wine composition without increasing vine vigor. However, we know little about the impact of this practice on phenolic compounds and yeast assimilable nitrogen (YAN). Adequate YAN is required for an efficient and complete fermentation, while phenolics are particularly important for the sensory profile of red wines. The goal of this study is to test the impact of foliar urea application at veraison, compared to the traditional soil-applied nitrogen fertilization early in the season, on Syrah berry and wine composition in field conditions.

As greenhouse gas emissions continue to rise, climate projections indicate an increased likelihood of heat waves and drier conditions in canada. these changes pose significant challenges to grapevine cultivation, particularly during critical growth stages such as new plantings. interspecific hybrid grape varieties, developed through different breeding programs that combine vitis vinifera with more robust species like v. riparia and v. labrusca varieties, are often touted for their potential resilience to environmental stress.

In this video recording of the IVES science meeting 2021, Johanna Döring (Hochschule Geisenheim University Department of General and Organic Viticulture, Geisenheim, Germany) speaks about the comparison of integrated, organic and biodynamic viticultural practices. This presentation is based on an original article accessible for free on OENO One.