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The winery’s 2009 Cabernet Sauvignon was
aged for two years under water, California winemaker Gustavo Gonzalez, of Napa
Valley winery Mira, is overseeing the project in which barrel-fermented
Cabernet Sauvignon was bottled and then dropped in secure crates into the
Atlantic Ocean, off the coast of South Carolina, US.
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“The first wine we brought up was analysed against the same vintage aged
on land,” he told The Miami Herald. “Chemically they were identical but
there was a distinct difference in the wines’ taste and aroma. The submerged
wine had aged nicely with well structured tannins.”
You can read more at http://www.thedrinksbusiness.com/2014/11/underwater-wine-ageing-deemed-a-success/
The real difference is that the wine was put into the bottle after barrel aging on the land then submerged. Walker Romantica put the barrel into a protective package and then submerged it. The true aging and the reactions of the alcohol and the barrel are what is truly happening with the "Seven Fathom" process. I think that the wine makes would find better results if the barrel itself is submerged instead of bottled wines. ;o)