Evaluation of wood starch content on bench grafting success rate in grapevine

Evidence for a specific effect of soil mineral composition on wine character is largely anecdotal. However, soil potassium supply to the vine must be properly balanced between deficiency and excess for good fruit quality.

Aim‐ Rootstocks provide protection against soil borne pests and are a powerful tool to manipulate growth, fruit composition and wine quality attributes

Several classes of flavonoids, such as anthocyanins, flavonols, flavanols and flavones, undergo a slow H/D exchange on aromatic ring A, leading to full deuteration at positions C(6) and C(8). Within the flavanol class, H-C(6) and H-C(8) of catechin and epicatechin are slowly exchanged in D2O to the corresponding deuterated analogues; even quercetin, a relevant flavonol representative, shows the same behaviour in a D2O/DMSOd6 1:1 solution. Detailed kinetic measurements of these H/D scrambling processes are here reported by exploiting the time-dependent changes of their peak areas in the 1H-NMR spectra taken at different temperatures. A unifying reaction mechanism is also proposed based on our detailed kinetic observations, even taking into account pH and solvent effects. Molecular modelling and QM calculations were also carried out to shed more light on several molecular details of the proposed mechanism.

AIM: Vine diseases are still responsible for economic losses. Previous study in our laboratory, have shown effects of oenological tannins against Botrytis cinerea1,2. According to this, the aim was to evaluate the wine protection by oenological tannins against an another disease, the downy mildew. METHODS: During the 2020 vintage, infected grapes by downy mildew (Vitis vinifera cv. Merlot) were collected from the dispositive ResIntBio. The 100 kg were crushed, destemmed and dispatch into 10 aluminium tanks. SO2 was added at 3 g/hL. Oenological tannins (grape, quebracho, ellagitannin or gallotannin) were added at 100 g/hL into eight different tanks (4×2 tanks). The two last tanks were considered as control without addition of oenological tannins. Alcoholic fermentation was achieved with Actiflore 33® at 20 g/hL. Malolactic fermentation was achieved with Lactoenos B7at 1 g/hL. Finished wines were sulfited to obtain 45 mg/L of total SO2.

AIM Verdicchio and Lugana are two Italian white wines produced in the Marche and Garda lake regions respectively. They are however obtained using grape varieties sharing the same genetic background, locally known as Verdicchio in Marche and Trebbiano di Soave in Garda. Anecdotal evidence suggests that these two wine types exhibit distinctive aroma features. The aim of this work was to explore the existence of a recognizable odour profile for Lugana and Verdicchio, and whether specific aroma chemical markers could be identified. METHODS 13 commercial wines, 6 Lugana and 7 Verdicchio were used. Sensory analysis was done using sorting task methodology, assessing only odor similarities. A total of 53 volatile compounds were identified and quantified GC-MS analysis. Aging behaviors were also evaluated after an accelerated aging at 40 ° C for 3 months. RESULTS HCA analysis of sorting task data identified indeed two groups: one characterized by floral and minty notes and mostly associated with Lugana wines, the other characterized by spicy and toasted aromas and mostly associated with Verdicchio. From a chemical point of view, major differences between the two wines types were observed for cis-3-hexenol, methionol, phenylethyl alcohol, and geraniol.