Comparison between the volatile chemical profile of two different blends for PDO “Valpolicella Superiore”

Hydroxytyrosol (HT) is a bioactive phenolic compound with antioxidant activity. Yeast synthetise tyrosol from tyrosine by the Ehrlich pathway which is subsequently hydroxylated to HT. The aim of the present work is to develop and validate an UHPLC–HRMS method to assess the metabolites involved in this pathway as well as to screen Spanish commercial wines for HT bioactive compound.

Consumer preference favors flint-glass wine bottles over the traditional dark-colored, but it is documented that light exposure can cause white wines to produce off-aromas and change in color, and consequently da[1]mage their quality. Aim of the study was to study the white wine shelf life under the typical supermarket conditions, by recording the light and temperature exposure, the colorimetric changes, and the light-strike fault. METHODS: One pilot experiment based on two white wines and eight-time points and one kinetic experiment based on four white wines and seven-time points were designed and realized using a typical supermarket shelf for 32 and 50 days, correspondently. By installing prototype sensors at 32 points of the shelf, the temperature, UV, IR, and Visible light exposure were registered every 10 min. Approximately 600 commercial wines, bottled in flint and colored glass, were used. The colorimetric changes of the wines were registered and the light-strike fault was evaluated.

Developments in high-throughput sequencing (HTS) technologies allow us to obtain large amounts of microbial information from wine and must samples. Thus approaches, that are aimed at characterising the microbial diversity during fermentation, can be enhanced, or possibly even replaced, with HTS-based metabarcoding. To reduce experimental biases and increase data reproducibility, we compared 3 DNA extraction methods by evaluating differences in the fungal diversity with Riesling alcoholic fermentation samples at four different vineyards. The fungal diversity profiling was done using the genetic markers ITS2 and D2 using metabarcoding. The extraction methods compared consisted of a commercial kit, a recently published protocol that includes a DNA enhancer, and a protocol based on a buffer containing common inhibitor removal reagents. All methods were able to distinguish vineyard effects on the fungal diversity, but the results differed quantitatively.

Le lien fonctionnel entre typicité et terroir a été étudié en prenant en compte deux dimensions importantes : le type de sol et la date de vendanges. Ces deux facteurs sont, à des degrés divers

The Champagne vine-growing region has played a pioneering role in the delimitation of appellations of origin (AOC). The implementation of the Act of July, 22nd 1927 has led to drawing up lists of vine plots based on the criterion of vine cultivation antecedence.