Options to replace or reduce the sulphite content in Tannat red wines produced with minimal intervention

Ultra-High Pressure Homogenization (UHPH) is an innovative, efficient and non-thermal technology that can be applied at different stages in winemaking in order to reduce or avoid the use of sulphites. During 2022 vintage, a batch of Xarel·lo must was processed by UHPH at 300 MPa with an inlet temperature (Ti) of 4 ºC. In order to verify the influence of the UHPH treatment in wine characteristics, alcoholic fermentations with this must (UHPH) were carried out and compared with a control batch (without SO2 addition (C)) and a sulphited batch, in which 60 mg/L of total SO2 (SO2) were added.

In winemaking grapes, it is known that most aroma compounds are present as non-volatile precursors, such as glycosidic precursors. In fact, there is strong evidence supporting the connection between the content of aroma precursors and the aromatic quality of wine [1]. Acid hydrolysis is preferred to reveal the aroma potential of winemaking grapes, as it predicts more accurately the chemical rearrangements occurring during fermentation in acidic environments [2]. In this study, a method involving a fast fermentation followed by acid hydrolysis at 75ºC was used to evaluate the accumulation of aroma compounds over time in fractions obtained from six different varieties of winemaking grapes.

The definition of soil health is complex due to the lack of agreement on adequate indicators and to the high variability of global soils. Nevertheless, it has been widely used as synonymous of soil quality for more than one decade, and there is a consensus warning of scientists that soil quality and biodiversity loss are occurring due to the traditional intensive agricultural practices.
In this work we monitored a set of soil parameters, both physicochemical and microbiological, in an experimental vineyard under three different management and land use systems: a) addition of external organic matter (EOM) to tilled soil; b) no tillage and plant cover between grapevine rows, and c) grapevines planted in rows running down the slope and tilled soil.

Given that climate change is a continuous process, it is necessary to constantly search for new strategies that help the viticulturist sector to mitigate its consequences. All adaptation strategies will have a greater or lesser effect that in turn will be marked by the times of action. As a long-term action, a genetic breeding program to obtain new varieties descendant from Monastrell has been developed in the Region of Murcia (more specifically, in the IMIDA Research Center) since 1997. In this program, new red varieties have been developed through directed crosses of the Monastrell variety with other varieties such as Cabernet Sauvignon, Tempranillo and Syrah.

The root and shoot abscisic acid (ABA) accumulation in response to water deficit and its relation with stomatal conductance is longtime known in grapevine. ABA-dependent and ABA-independent signalling response to osmotic stress coexist in sessile plants. In grapevine, the signaling role of ABA in response to water stress conditions and its influence on berry quality is critical to manage grapevine acclimation to climate change.