Bordeaux (AFP)

They have come back from afar after a trip in the extreme conditions of space: in Bordeaux, bottles of Petrus and vine shoots are analyzed by researchers who are developing an experiment on micro-gravity, the accelerating potential of more agriculture. "resilient" on earth.

Good news: even after 14 months in space, this 21-year-old grand cru - around 5,000 euros - has remained "a very great wine", according to preliminary findings from the Institute of Vine and Wine Sciences (ISVV) of the University of Bordeaux unveiled Wednesday.

Since February, the ISVV, in Villenave-d'Ornon (Gironde), has been responsible for analyzing the 12 bottles of this "legendary" wine and half of the 320 Merlot and Cabernet Sauvignon vine shoots sent for 14 and 10 respectively. months on the International Space Station (ISS), at the initiative of the European start-up Space Cargo Unlimited (SCU).

This launch was part of its WISE mission, which aims to "find solutions for the agriculture of tomorrow" by betting on the influence of microgravity on living things.

"Our approach is to think that plants which have been able to resist the absence of gravity will be more resilient, more able to react to stresses (...) such as climate change", explains the Girondin Nicolas Gaume, president and co-founder with Emmanuel Etcheparre of SCU.

About fifteen researchers are involved in this private applied research program in partnership with the University of Erlangen (Germany), the National Center for Space Studies (Cnes) and the European Space Agency (ESA).

Having returned to land in mid January, half of the vine shoots were replanted in the greenhouses of the world leader in vineyard nurseries, the Mercier Group, for future outlets.

The other half, at the ISVV, is now compared and analyzed with identical batches that have remained on earth.

In parallel, a test carried out on March 1 made it possible to obtain "a first photograph" of the space odyssey of wine.

On that day, two "anonymized" bottles of Petrus were blinded to a panel of 12 people - amateurs and experts.

"Unanimous" verdict: "the + space wine + has been very well evaluated sensorially", summarizes Philippe Darriet, director of the oenology research unit at ISVV.

In 11 out of 12 cases, "differences" were noted, particularly in color, and sometimes in nuances of smell and taste.

- "Stress prodigious" -

For oenologist Jane Anson, "the big difference" between the two wines was above all "visual".

"Both are really magnificent", she assured AFP at the beginning of March while judging the terrestrial wine "a little more tannic, younger" compared to the "celestial" wine whose "more floral aromatic" stood out "more".

The winemaker Franck Dubourdieu did not perceive any "significant" difference and hails a "success": "the wine of space has not deteriorated".

These first impressions must still be confirmed by physicochemical analyzes at the ISVV while at the same time, scientists are monitoring the evolution of the vine shoots which have vegetated for 10 months in weightlessness, in lightless cells with controlled humidity.

"Gravity is a central parameter of life, the only one that has never evolved on Earth, unlike temperature or humidity. When we expose plants to this absence of gravity, we subject them to tremendous stress, which could accelerate certain natural evolutions ", advance Nicolas Gaume.

If it is too early to draw conclusions, the researchers have already noted that "the" space "vine plants grew faster than their twins remained on earth", rejoices Nicolas Gaume.

But it will be necessary to wait 3 years to know if certain plants have undergone epigenetic modifications (in the expression of genes).

"The final expectation is to challenge the plants and see if they have acquired better tolerance to pathogens such as mildew", and to "a context of climate change", adds the scientist, Stéphanie Cluzet, research director and professor at ISVV.

Next step for the WISE mission?

test a fermentation in zero gravity.

© 2021 AFP