Effects of foliar application of methyl jasmonate and/or urea, conventional or via nanoparticles, on grape volatile composition.

Background: Viticulture has adapted foliar applications of biostimulants as a tool to improve crop quality. Recently, nanotechnology has been incorporated as a strategy to reduce the loss of biostimulants and treat nutrient deficiencies. Therefore, the present study aimed to investigate the effect of foliar applications of amorphous calcium phosphate nanoparticles (ACP) doped with methyl jasmonate (ACP-MeJA) and urea (ACP-Ur), individually or together (ACP-MeJA+Ur), on the content of volatile compounds in 'Tempranillo' grapes, compared to the conventional application of MeJA and Ur, individually or in combination (MeJA+Ur).

Vine Foliar Treatments at Veraison and Post-Veraison with Methyl Jasmonate Enhanced Aromatic, Phenolic and Nitrogen Composition of Tempranillo Blanco Grapes.

Methyl jasmonate (MeJ) is an elicitor that, when applied in the vineyard, can improve grape quality. There are several studies about the MeJ influence on red grape varieties; however, to our knowledge, there is little information about white grape varieties, specifically Tempranillo Blanco. Therefore, the aim of this work is to evaluate the effect of MeJ foliar treatments, carried out at veraison and post-veraison, on the aromatic, phenolic and nitrogen composition of Tempranillo Blanco grapes.

Could foliar applications of methyl jasmonate and methyl jasmonate + urea improve must grape aroma composition?

Background: Grape aromas are formed by a great number of volatile compounds. Methyl jasmonate (MeJ) and urea (Ur) foliar applications have been studied to improve grape quality, but their combined application has never been studied.

Results: In both seasons, MeJ application enhanced terpenoids and C6 compounds synthesis, though decreased alcohols content.

Optimization of thin film-microextraction (TF-SPME) method in order to determine musts volatile compounds.

It is well known that grape aromatic composition is directly correlated to the final wine quality. To determine this composition, a previous stage of selective extraction is necessary, since the aromatic compounds are found in very low concentrations in the grapes. Therefore, in this work, the thin film microextraction technique (TF-SPME) was optimized, for first time, with the aim to analyze the volatile composition of the grape musts.

Pre-fermentative maceration with SO enhanced the must aromatic composition.

SO is the additive most used in winemaking, due to its antioxidant and antiseptic activities. There have been several studies focused on these activities; however, there are hardly any studies that address its role as extractant. Therefore, the objective of this work was to study the effect of SO on the must volatile composition after a pre-fermentation maceration.