Soil and nutritional survey of Greek vineyards from the prefecture of Macedonia, Northern Greece, and from the island of Santorini

Aim: This work studies how successive O2 saturations affects the color and hydroxycinnamic
acids concentration in the absence and presence of laccase from B. cinerea with the aim of better understanding the browning processes.

Materials and methods: Grapes of Muscat of Alexandria were harvested and pressed with a vertical press to extract 60% of their juice. Aliquots of 30 mL of this must were placed in 60 mL flasks equipped with a pill (PreSens Precision Sensing GmbH) for measuring oxygen by luminescence (Nomasense TM O2 Trace Oxygen Analyzer).

Viticulture is facing many challenges due to climate change effects with increasingly attention to save resources, such as water, considering that drought events have been predicted to dramatically increase over the next future. Thanks to the -omics techniques, research pushed forward knowledge to deepen facets of drought response in diverse grapevine-rootstock combinations. However, the regulatory mechanisms orchestrating adaptation strategies during drought and recovery in grafted grapevines need further exploration. Herein, we combined ecophysiological, biochemical and molecular approaches to unravel drought and recovery-induced changes in potted Nebbiolo (NE) plants grafted onto three different rootstocks (3309, Kober5BB, Gravesac), by analysing root and leaf tissues.

In order to study the impact of climate change on Bordeaux grape varieties and to assess the adaptation capacities of candidates to the grape varieties of this wine region to the new climatic conditions, an experimental block design composed of 52 grape varieties was set up in 2009 at the INRAE Bordeaux Aquitaine center. Among the many parameters studied, the three main phenological stages of the vine (budburst, flowering and veraison) have been closely monitored since 2012. Observations for each year, stage and variety were carried out on four independent replicates. Precocity indices have been calculated from the data obtained over the 2012-2021 period (Barbeau et al. 1998). This work allowed to group the phenological behaviour of the grapevine varieties, not only based on the timing of the subsequent developmental stages, but also on the overall precocity of the cycle and the total length of the cycle between budburst and veraison. Results regarding the variability observed among the different grape varieties for these phenological stages are presented as heat maps.

Untargeted metabolomics has proven to be an effective method to study the impact of the terroir on metabolic profile of wines. In this context, the aim of this study was to evaluate the effects of different soil types on the chemical composition of Mediterranean red wines, through 1H-NMR metabolomics combined with chemometrics.Grapes from Nero d’Avola L. red cultivar cultivated on four different soil types were separately vinified to obtain four different red wines.One milliliter of raw wine was analyzed by means of a Bruker Avance II 400 spectrometer operating at 400.15 MHz

1,1,6-Trimethyl-1,2-dihydronaphthalene (TDN) is a controversial aroma component found in Riesling wines. It belongs to the family of C13-norisoprenoids and is mainly associated with kerosene/petrol notes. TDN can add complexity to the wine aroma at medium – low concentrations and deteriorate the wine bouquet when its content is high. No TDN aromas are usually perceived in young Riesling wines, but they can appear after several years of aging due to the gradual formation of TDN. Management of TDN in Riesling wines is an actual task, since global warming can promote formation of this compound and compromise the aromatic composition of wine. Therefore, the aim of the current work was, firstly, to study the sensory particularities of TDN in Riesling wine at various concentrations. Secondly, to investigate the ability of bottle closures to absorb (scalp) TDN from Riesling wine under various storage conditions. These studies also include the comparative assessment of our findings with previously published data. METHODS: sensory analysis, GC-MS (SBSE), HPLC,1H-NMR and other methods related to the synthesis and determination of TDN. RESULTS: First of all, the method of the synthesis of highly purified TDN (95% and 99.5%) was optimized [1].