Have the best Bordeaux wines been drunk already? A reflection on the transient nature of terroir, using case study Australia

This presentation aims to demonstrate that the value attributed to wine as we today know it is based on three factors: 1) sensory balance, 2) personality, and 3) bioactivity.

Since 2012, EU Commission approved compulsory labeling of wines treated with allergenic additives or processing aids “if their presence can be detected in the final product” (EU Commission Implementing Regulation No. 579/2012 of 29 June 2012). The list of potential allergens to be indicated on wine labels comprises sulphur dioxide and milk- and egg- derived fining agents, including hen egg lysozyme, which is usually added in wines as preservative. In some non-EU countries, the list includes gluten, tree nuts and fish gelatins. With the exception of lysozyme, all these fining proteins were long thought to be totally removed by subsequent winemaking processings (e.g. bentonite addition).

The maintenance and valorization of genetic diversity is an undoubtable resource for the viticulture of the future, since the climate crisis is forcing us to think of new, more resilient varieties. For this reason, the grapevine germplasm of the Fondazione Edmund Mach has been continuously expanded in the last decade to a total of 3,120 accessions, whose trueness-to-type has been verified by means of the universal set of nine microsatellites. About two thirds are V. vinifera subsp. vinifera accessions, while the rest consists of naturalized and selected hybrids, V. vinifera subsp. sylvestris, and pure species. The genetic material has also been characterized over three consecutive years for ampelographic, vine development, and biotic stress response traits to be exploited for experimental purposes.

The online monitoring of fermentative aromas provides a better understanding of the effect of temperature on the synthesis and the loss of these molecules. During fermentation, gas and liquid phase concentrations as well as losses and total productions of volatile compounds can be followed with an unprecedented acquisition frequency of about one measurement per hour. Access to instantaneous production rates and total production balances for the various volatile compounds makes it possible to distinguish the impact of temperature on yeast production (biological effect) from the loss of aromatic molecules due to a physical effect³.

Given the impact of climate change on viticulture in the Region of Murcia, this paper attempts to expose the possibility of using genetic improvement as a dilemma that allows access to new descendant varieties of the autochthonous variety Monastrell crossed with varieties such as Syrah and Cabernet. Sauvignon, thus obtaining hybrids (Gebas and Myrtia). In it, the chromatic parameters and the phenolic profile of the new varieties will be compared with those obtained by the Monastrell variety at two moments during maturation (12 and 14 º Baumé), to check if the results would allow earlier harvests in these new varieties thus avoiding the decoupling between phenolic and technological maturity, while improving the quality of grapes and wines.