Ageing wine beneath the sea: science and benefits

Underwater wine ageing is an innovative trend. It was initiated in 2007 by Bodega Crusoe Treasure. This process has captured the attention of winemakers, sommeliers and wine lovers around the world. Unlike traditional cellar ageing, this method harnesses the unique conditions of the marine environment to transform the wine’s evolution. But is it truly beneficial? What are the differences compared with ageing on land? Discover it by tasting our wines!

What is underwater wine ageing?

Underwater ageing, or underwater treasure ageing (a term we coined at Crusoe Treasure to define our process), consists of submerging bottles or wine barrels on the seabed for a set period of time. This process allows the wine to evolve under natural conditions that differ from those of a conventional cellar.

This concept is not new: bottles of wine have been found perfectly preserved for decades in shipwrecks, sparking interest in exploring this method. However, carrying it out on an artificial reef that helps the sea has been the innovation of Bodega Crusoe Treasure, the world’s first artificial reef winery.

Key factors of the marine environment in wine ageing

Underwater treasure ageing affects the wine Crusoe Treasure through a combination of environmental factors not found in a traditional cellar:

1. Low temperature with constant changes 
   • The Cantábrico Sea—and specifically our location—maintains more stable temperatures than a winery on land, avoiding abrupt thermal fluctuations that can affect the wine’s evolution. Constant but very slight thermal changes occur, with the annual temperature ranging from 12 ºC to 18ºC.
2. Total darkness
   • Unlike wineries, where there is a certain level of ambient light, on the seabed of the Cantábrico Sea, inside our artificial reef winery, there is complete darkness, protecting the wine from premature oxidation caused by light.
3. Marine and underwater pressure
   • Because of the depth, our wines are subject to a constant pressure of 3 atmospheres, which varies under the influence of waves, currents and tides (the latter produce changes of up to 0.5 atm every 6 hours). The pressure on the bottles is constantly changing. As depth increases, the pressure on the bottle’s cork becomes greater. The cork acts as a membrane—and that is where the magic begins.
4. Micro-oxygenation of the wine through the sealing wax and cork
   • In bottles with the microporous natural seals we designed, gas exchange is lower than on land, but constant, encouraging controlled micro-oxygenation without the risk of excessive oxidation.
5. Movement and marine currents
   • We have discovered that slight vibrations and marine currents influence the molecular structure of the wine, helping its components integrate more homogeneously.
6. Humidity/water
   • Under the sea, humidity is 100%, affecting the cork and surrounding the bottle.
   • It has been scientifically demonstrated that liquids (a bottle surrounded by seawater) respond to sound, vibrations and light very differently from air (a bottle on land).

Differences compared with cellar ageing

Factor	Ageing on Land	Ageing Under the Sea
Temperature	Regulated.	Continuous thermal changes, potentially numbering in the hundreds per hour due to currents and storms.
Gravity	The wine is subject to terrestrial gravity.	Lower gravity under the sea.
Pressure	Constant atmospheric pressure.	Constantly changing due to tides and waves.
Oxygenation	Controlled according to the type of cork and storage conditions.	Natural micro-oxygenation according to the sealing wax and cork, exposed to continuously changing pressure.
Movement	Static on shelves and/or in barrels.	Constant movement and continuous vibrations.

What benefits does underwater ageing bring to wine?

The wines Crusoe Treasure begin with exceptional quality on land, crafted by our master winemaker Antonio Palacios. After ageing in barrels, they are bottled and submerged in our artificial reef winery, giving them special, distinctive and more highly valued characteristics:

- Greater softness and balance – The tannins integrate more harmoniously, reducing their astringency.

- More intense aromas – More complex and developed notes can be perceived.

- Greater freshness and balanced acidity – Thanks to the sea’s stable temperature.

- Silkier texture – A change in the wine’s perception on the palate can be observed.

- Evolution once uncorked - Remarkable evolution in the glass from 15 minutes to three days. When our wines are kept open in a cool place away from excessive light, they continue to evolve positively for up to three days.

- Exclusivity – These are distinctive wines, with limited editions and unique designs.

- Evolution once on land - Once recovered from the sea, the wine continues to evolve positively in the cellar, following the path of evolution already begun. We have demonstrated that, after 10 years from extraction from the sea, our wines are exceptional when opened, and their colour shows that they still have a long life ahead in bottle.

The scientific validation of the underwater ageing of Crusoe Treasure

Antonio T. Palacios, a Doctor of Enology and owner of Excell Ibérica, a leading analytical microbiology laboratory in Spain (Logroño) and France (Bordeaux), has conducted thousands of analyses and tastings for both the LSEB project (Plentzia Underwater Beverage Ageing Laboratory) and Bodega Crusoe Treasure. His studies confirm that wine evolves differently beneath the sea, under a universe of conditions entirely distinct from those found in a land-based cellar. These investigations have demonstrated that marine factors generate a singular transformation in the wine’s structure and aromatic profile, opening up new perspectives in modern enology.

Thanks to the combination of stable temperature, darkness, pressure and natural micro-oxygenation, our wines develop unique aromatic and flavour profiles.

If you are looking for a distinctive and exclusive wine experience, taste and gift an exceptional wine that completes its ageing process beneath the Cantábrico Sea.