A new chemiluminescence method related to molecules derived from Botrytis cinerea for characterization of Aszu wines from Tokaj, from Hungary

Port wine value is related to its molecular profile resulting from the changes occurring during the ageing period. It is of empirical knowledge that the style is greatly affected by the oxidation regimens, i.e. bottle versus barrel storage

Bois noir is the most widespread phytoplasma grapevine disease in Europe. It is associated with ‘Candidatus Phytoplasma solani’. In symptomatic grapevines cv. ‘Zweigelt’ infected with ‘Ca. P. solani’ compared with uninfected grapevines, metabolic pathways associated with phosphorylated sugar production were induced both at the transcriptional level and at the level of activity of the corresponding enzymes (Dermastia et al., 2021, Int. J. Mol. Sci. 22: 3531). In particular, the expression of gene coding for phosphoglucoisomerase was upregulated, resulting in increased phosphoglucoisomerase enzyme activity.

Over the last years, due to climate change, several red wines, such as the Sangiovese wines, have been often subjected to loss of clarity due to the formation of deposits of fine needle-shaped crystals. This phenomenon turned out to be due to an excess of quercetin (Q) and its glycosides (Q-Gs) in wines. These compounds are synthesized to a large extent when grapes are excessively exposed to UVB radiations in vineyards[1]. Unfortunately, it is not easy to predict the degree of Q precipitation because its solubility strongly depends on the wine and matrix composition[2].

Many factors influence aging of bottled wine, oxygen transfer through the closure is included. The maximum uptake of wine before oxidation begins varies from 60 mg.L-¹ to 180 mg.L-1 for white and red wines respectively [1].
The process of bottling may lead to considerable amounts of oxygen. The actual contribution of the transfer through the closure system becomes relevant at the bottle storage, but the amounts are small compared to prepacking operations [2] and to the total oxygen attained during filling.

Faced with the likely withdrawal of commercial specialities from use in the short to medium term, France has decided to implement an ambitious action plan to anticipate and avoid withdrawal without alternative solutions. The French wine industry (cniv and ifv) has been heavily involved in this action to define priorities. faced with the risk of the withdrawal of multi-site fungicides (folpel, dithianon, copper) coupled with the probable reduction in single-site fungicide solutions, mildew and black rot have been identified as the priority uses.