The best way to preserve half-drunk bottles of wine

(WALL STREET JOURNAL) I rarely savemy unfinished bottles of wine. Few wines are as good, let alone better, on the second or third day as they are on the first. I’m more likely to give away half-finished bottles to my friends and neighbors than I am to squirrel them away for another day—although, to be honest, there’s never a lot of unfinished wine in our house.

I realize that I’m very much in the minority. Almost everyone I know seems to have several half-drunk bottles stored on their kitchen counters or inside their refrigerator doors. I don’t know if that means they’re drinking much more than I am, or much less, but it may help account for the growing market for wine-preservation tools. Marshall Tilden III, director of sales at Wine Enthusiast, a leading retail and wholesale purveyor of wine accessories based in Mount Kisco, N.Y., said sales of preservation devices are up 15% last year over 2010 figures. Sales of expensive systems such as Coravin (from $299) and EuroCave Wine Art (from $399) are particularly strong, he added.

There are two basic ways to keep an open bottle of wine fresh and protect it against oxidation (air is the enemy of wine, after all): Either the air in the bottle is pumped out or the remaining wine is covered with a protective blanket of gas. The simplest air-pump system is a small plastic device that allows wine drinkers to remove air from the bottle by hand. Vacu Vin’s Wine Saver, which debuted 30 years ago, is probably the best known. The simplest—and cheapest—form of protective gas comes in a can and is sprayed directly into the bottle.

The Coravin Wine System has taken wine-preservation to the next level by letting oenophiles serve wine without ever actually uncorking the bottle. The device, which looks like a child’s microscope, plunges a thin, medical-grade needle into the bottle through an intact cork to remove small amounts of wine at a time. It then fills the empty space with argon gas. The needle is so slender that when it’s removed the cork closes back onto itself, theoretically keeping the wine in the same state as an unopened bottle.

Using gas in the preservation process can sometimes be problematic; the Coravin was recalled in 2014 when 13 bottles broke after being injected with gas. A friend of mine was badly injured when his bottle burst. Founder Greg Lambrecht told me that bottles with pre-existing flaws were at fault. My friend, however, said his bottle wasn’t flawed. The devices weren’t removed from the market; instead the company notified clients to not use the Coravin until they received repair kits that included neoprene sleeves to cover bottles and contain any breakage. Sleeves are now included with each new system.

My friend hasn’t touched his device again, but the Coravin has become popular with wine professionals, especially sommeliers. They say it allows them to sample expensive bottles over a period of weeks and even months. Many restaurants in New York and other cities now have special sections on their wine lists that feature “Coravin wines,” usually pricey, rare bottles that wouldn’t otherwise be financially feasible to sell by the glass. I’ve sampled a few of these wines and found that even though they were a couple of weeks old, they were remarkably fresh.

I’ve never used any wine-preservation devices, but I have wondered from time to time how well they work. I decided to try a few of the more basic tools and conduct my own highly unscientific test.

I bought a Vacu Vin Wine Saver ($10); a bottle of Private Preserve spray ($15), a blend of nitrogen, argon and carbon dioxide that’s said to keep wine fresh “days, weeks, months and years”; and Metrokane’s Rabbit Electric Wine Preserver ($40), a battery-powered flashlight-size device with a light that illuminates when the air is removed from the bottle. I added a bag of glass marbles to my stash after reading an English wine collector named Ian advocate using them to fill half-full bottles in the Wine Berserkers online forum. (The marbles displace the air in the bottle, according to Ian.)

I tested the devices with six bottles of 2012 Famille Perrin Côtes du Rhône Villages ($12), a bright and lively basic red. After tasting each wine to make sure it was sound, I poured half of the wine out, ensuring each bottle had the same amount left.

The first bottle I simply recorked and put into the refrigerator. I filled the second up with marbles before placing it in the fridge. My husband was a bit skeptical about this particular method. Had I cleaned the marbles well? he wanted to know. For the third bottle, I squirted gas from the Private Preserve can as directed (“one long spray, three short sprays”), then replaced the cork. I pumped the air out of the fourth and fifth bottles—first with the Vacu Vin, then with the Rabbit—and put them in my cellar. The sixth bottle went into the freezer, since a wine-collector friend swore that was the best way to keep an open bottle fresh.

I waited two days before tasting the wines. The wine under the Vacu Vin tasted the freshest by far, with the liveliest aromas. The second-best was the wine I’d recorked and put in the fridge. The wine under the Rabbit tasted reasonably fresh but lacked aroma. I wondered if it had pulled all the volatile components—the aromatics—out of the bottle along with the air.

The wine with the marbles tasted a bit musty. Did Ian’s trick only work with English marbles? I emailed him but never heard back. The wine under the spray tasted like cardboard. Had I sprayed the gas into the bottle for one short and three long instead of one long and three short? I didn’t unfreeze the last bottle, deciding to open it on the second round.

I reapplied the various devices to the wines once more and returned the bottles to their designated places. Two days later, I uncorked all the bottles and tried the wines once more. On day four, the marbled-wine was pretty much dead in the bottle. Ditto the wine with the spray. The wine that I’d simply recorked and refrigerated tasted flat—the aromas were gone—as was the wine under the Rabbit, although the latter still had some life and a lively texture. The frozen wine, which took about four hours to melt and reach room temperature, tasted close to the original version of the wine, but it too lacked aroma. Once again, the Vacu Vin wine was the freshest, with a bit of bright, cherry aroma.

Two days later, I tried the three bottles that made the final cut: the Vacu Vin, the Rabbit and the (re)frozen. The Vacu Vin wine had some lingering aromatics, but it was pretty much gone—flat and fruitless. (The Vacu Vin spokesperson did suggest “three to five days” was the ideal time frame for the tool.) The Rabbit wine was a bit better, but the frozen wine was flat and featureless.

It had been an interesting experiment. I would definitely use the Vacu Vin again but I’m not so sure about the other devices. I probably wouldn’t freeze another wine again anytime soon either, although my wine-collector friend recently called to tell me he’d unfrozen a half-empty bottle of 2000 Vega-Sicilia and thought it was “even better” after its deep freeze. I’d still rather give away my half-full bottles to friends on the day I open them rather than recork them and serve the wines several days or weeks later—to those very same friends.