Until about a month ago, whenever I was asked how long an opened bottle of wine would last and which method for keeping it fresh was best, my response was discouraging. Wine, I believed, deteriorated quickly when exposed to oxygen; even after 24 hours, most wines would have lost a lot of their character and charm. As to which preservation system worked best, I was unsure. So I decided to experiment with several methods to find out. And frankly, I was shocked. The outcome was nothing short of startling.
The experiment took 54 bottles of wine. I tested three easy-to-use, widely available systems: Private Preserve (about $10), a canister of harmless inert gases, which you spray into the bottle, supposedly displacing the oxygen; VacuVin Wine Saver (about $10), a small hand-pump and rubber seal ― you restop the bottle, then pump out the oxygen, theoretically creating a vacuum; and, finally, simply pouring the remaining wine into a smaller bottle, filling it to the top so there's no air inside, then capping it tightly. I also compared these methods to using no preservation system at all ― that is, just restopping the wine bottle with its original cork.
For each preservation system, I removed the same amount of wine from the original bottle ― 175 milliliters, or about one quarter of the bottle (one generous glass) ― before resealing it. When it came to just recorking the bottle, I experimented with two variations. In one case, I removed one quarter of the wine, in the other case, half the wine.
To make the experiment more meaningful, I included time as a factor. Was it true that the longer a bottle had been open, the worse the wine tasted? To find out, I tested each preservation method on three different bottles ― keeping one resealed for one day, one for two days, and one for four days. And so the results would not apply to just one wine or grape variety, I performed the entire experiment on three different wines: Clos du Bois Chardonnay, Geyser Peak Cabernet Sauvignon, and Saintsbury Pinot Noir.
Finally, since I didn't want the experiment to reflect my judgment alone, I asked a winery owner and a wine enthusiast to join me in the tastings, which we did completely blind ― none of us knew which wine had been preserved with which system. Nor did we know which was the control wine (from a freshly opened bottle). We ranked the wines in taste from best to worst. My husband (a Stanford Business School graduate) tabulated the results.
• No taster consistently rated one preservation system best.
• No preservation system was rated better overall than any other.
• More surprising yet, no preservation system worked better than just recorking the bottle, no matter which variety or whether the wine had been opened for one, two, or four days.
• Wines that had been opened for four days didn't necessarily taste worse than wines that had been opened for only one day.
• And the most stunning revelation of all: In several cases, tasters preferred an opened wine to the control wine! After being opened for a day or more, the Chardonnay sometimes tasted softer and less oaky, the Cabernet rounder and less tannic. Even the Pinot Noir sometimes seemed more mellow, which some tasters liked.
As every scientist knows, conclusive experiments are difficult to design. And so a few caveats are in order. First, the wines were all kept at cool room temperature; at warmer temperatures, the results might be different. Second, after removing some of the wine, I recorked the bottles right away; wine left open during a two-hour dinner and then recorked might not keep as well. And finally, three wines ― however interesting the test results ― aren't a big sample. But I'll tell you one thing: This is the last time I'll pour a half-empty bottle of wine down the drain without giving it a second chance.
SUNSET'S STEAL OF THE MONTH: Bonny Doon Ca' del Solo Big House Red 1998 (California), $10. A terrific, juicy, berried wine with an appealing rustic edge. Made from Carignane, Sangiovese, Zinfandel, and other red varieties.
THE TEST WINES
The subjects for this experiment were all delicious ― and very good examples of their respective varieties.
Clos du Bois Chardonnay 1998 (Sonoma County), $14. A nice, all-around Chardonnay, with creamy apple flavors laced with touches of vanilla and oak.
Geyser Peak Cabernet Sauvignon 1997 (Sonoma County), $17. Beautiful aromas and flavors of cassis, mint, and black raspberry wrapped in a plush texture.
Saintsbury Pinot Noir 1998 (Carneros, CA), $22. Supple and juicy, with aromas and flavors reminiscent of strawberry jam, mocha, and earth.