From north to south, Portugal’s geography and identity are shaped by the presence of the sea. This centuries-old relationship, which has inspired voyages, trade, and culture, is now opening the door to a new wine experience — not in traditional cellars, but in the quiet depths where bottles rest beneath the water. The phenomenon of aquatic or submerged wines promises to shake up oenology and open new horizons for wine tourism.
What are submerged wines?
These are wines that, instead of ageing in cellars, spend months or even years underwater — in the sea, rivers, reservoirs, or flooded mines. Down there, they are exposed to a unique maturation environment: high pressure, total darkness, stable temperatures, and, in the ocean, the constant movement of currents.
Although this technique has gained popularity in recent years, fascination with underwater ageing rose to prominence after a remarkable discovery. In 2010, divers found the wreck of a ship in the Baltic Sea containing 168 bottles of champagne, perfectly preserved after more than a century. Dominique Demarville, oenologist for the Veuve Clicquot house, tasted and studied their contents, noting that the sparkling wine was in excellent condition and displayed unique sensory characteristics shaped by the extreme conditions of the seabed.
The scientific perspective
At the scientific conference “Submerged Secrets: The Enigma of Underwater Wines”, held in Sines during Portugal’s first national event on the subject — the Subaquatic Wine Tourism Experience — two specialists from the University of Évora shared valuable insights.
Cristina Barrocas Dias, PhD, from the Department of Chemistry, explained that wine is “a living being, constantly evolving.”
She added: “The temperature, light, and depth at which wine is submerged cause natural changes — in colour, astringency, and ageing itself.”
Maria João Cabrita, PhD in Agricultural Sciences, proposed a new concept: “If on land we talk about terroir, at sea we can speak of ‘marroir’.”
She extended the idea to underwater environments in general, noting that variations in pressure, absence of light, temperature, cork type, and water movement mean there is still no single explanation — each site and depth produces distinct results.
What did the tastings reveal?
During the event, Portugal’s first comparative Land vs. Sea tasting featured white, rosé, and red wines — as well as ginja and rum — aged underwater for between 12 and 15 months.
Main conclusions:
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White wines showed the most pronounced aromatic and flavour changes.
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Complex reds also displayed notable differences.
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Structured, higher-quality wines tend to evolve better.
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Some became rounder and smoother; others remained almost unchanged.
According to sommelier Rodolfo Tristão: “Submerged wines don’t always become smoother. Some actually develop higher acidity.”
He adds, with a touch of humour: “Wines are like people: sometimes, they just need a little more patience.”
Trend or lasting movement?
If “marroir” becomes part of wine lovers’ vocabulary, Portugal — with its long coastline and centuries-old wine tradition — could well lead this new wave. Until then, one thing is clear: wine, like the sea, still holds many secrets in its depths.
Want to know more?
Dive into Vinha.co.uk to explore the red wine Conde d’Ervideira Vinha da Água and see how it’s made.
