It was a steamy mid-July day, and there I was, lugging three opened bottles of wine in an insulated bag as I trekked from one prospective customer to the next. But as a professional wine salesman, I had confidence that the contents were in good shape, because I had sealed the bottles with my Vacu-Vin Wine Saver, whose sole mission is to protect wine from exposure to air, which accelerates oxidation.

Don’t get me wrong. Oxygen in wine isn’t all bad. Starved of it, a wine can go into what is known as reduction, which creates hydrogen sulfide aromas. Without any oxygen, the esters and aromas that we love to sniff would not be released when we open a bottle of wine. What’s more, in a controlled setting, oxidation gives us fabulous Sherry and Tokaji and Madeira wines.

Uncontrolled, however, exposure to air starts the slow process of oxidation, a time bomb that starts ticking the moment a cork is popped or a screw cap is untwisted. It causes the wine to smell increasingly less inviting and taste less fresh while on its way toward becoming undrinkable.

Because there are 25 one-ounce pours in every standard-size, 750 ml bottle of wine, salespeople can cart around opened bottles of wine for days — hence the popularity of the Vacu-Vin Wine Saver. The inexpensive pumping device comes with a rubber stopper that you stick into the bottleneck after you’ve poured some wine. To seal it, you place the gadget over the stopper, create a vacuum by hand-pumping the oxygen out of the bottle.

The next time you go to pour a taste of wine, you release the rubber stopper and hear the reassuring schwoop of a vacuum that’s been unsealed. That’s how you know the Wine Saver is working. Or is it?

Experiments in Wine Preservation

After finishing my sales call that hot July day, I made the first push to pump my Wine Saver and noticed that the wine in the bottle had jiggled a little. I could swear that I saw some tiny bubbles, which looked suspiciously like oxygen had gotten into the wine.

The Vacu-Vin Wine Saver is a marketing phenomenon. Tens of millions have been sold since the 1990s. You probably have one lying around somewhere. Despite the sales figures, a blogger and former wholesaler named John Cesano flatly states that the Vacu-Vin Wine Saver does not work and cites studies and articles that dispute the manufacturer’s claims.

To test Cesano’s claims, I once organized a blind tasting using three bottles each of two separate wines from the same vintage. I opened two bottles of both wines and poured enough from each to fill one glass, and dumped it. Then, with two of the opened bottles I put the cork back in, and on the other two I used the pump. The opened bottles stood alongside the unopened ones on a counter until the following day.

The next day, with all the bottles in brown bags, I invited a few people to participate in the blind experiment. I uncorked the two untouched bottles. They were going to be used as controls, to compare with the previously opened bottles. The guests tasted each wine without knowing anything about them or their treatment. Overall, the group said that the newly opened wines tasted fresher and brighter, but not one person could tell the difference between the bottles that had had the corks pushed back in and those that had been pumped.

It seems that most other wine preservation systems fare no better than the vacuum pump. By testing three popular wine-preservation systems, Alex Healey found that you derive only negligible benefit from using any wine preservation system on an opened bottle. That’s because by simply opening and pouring, you let in enough oxygen to begin oxidation.

As sommelierjournal.com blogger Jamie Goode has written, “The only way to truly preserve the wine is to use an inert gas to dispense the wine in the first place, preventing any oxygen pick-up.”

Goode is referring to the nitrogen systems used by some restaurants with wine-by-the-glass programs. They do work, and home versions can be had for $100 to $2,000, which hardly seems worth the investment just to save a little wine for a day or two.

There is, however, another way that’s simple and eminently affordable.

Cheap, Easy and Effective Ways to Preserve Wine

Wineries’ storage cellars are kept cool because vintners know that unless you apply inert gas, you cannot stop the oxidation process — though you can slow it with cool temperatures. Regardless of whether a wine is red, white or rosé, colder temperatures will delay oxidation.

Lucky you. You have something in your kitchen that is as good as a winemaker’s cellar. It’s called a refrigerator.

Your fridge will extend the life of a resealed bottle of wine by up to three days. After that, it’s likely to taste “flat.”

A couple of words of warning: Never use your refrigerator for long-range (months) storage of wine sealed with a cork. It’s not humid enough and can dry out the cork. Conversely, warm temperatures speed up oxidation of wines even in unopened bottles, so ideally you wouldn't store wine at temperatures above 68 degrees Fahrenheit (and never over 75 degrees) for more than a month or two.

Freezing also preserves wine — but who wants to wait for it to thaw? Besides, to freeze it, you have to open the bottle and pour it into a larger vessel that accommodates expansion of the frozen wine. After it’s thawed, the wine’s acidity may be reduced, though most people won’t perceive it in the taste, so it's a great way to preserve wine to use in cooking.

Another Approach to Conserving Wine

Let’s say you know in advance that you’re going to open a bottle of wine but you’re not going to finish it. One thing you could do is to buy wine in half bottles, known as splits. Unfortunately, you won’t find a wide selection of these (and you will pay a premium), but I often recommend that people do that anyway — once.

When you finish the smaller bottle, sanitize it in very hot water (no soap) and save it. Then, the next time you open a full-size bottle, immediately fill the split with the wine, cap it with the stopper of the larger bottle, and refrigerate. If you can’t find splits, you could use a jar of comparable size, like a canning or jelly jar, also sanitized.

Then there’s the least-glamorous-seeming way to preserve open wine. It’s called wine in a box. Housed in a bladder that contracts as you pour, this system prevents oxygen from getting in. They won’t last forever, but boxed wines will keep for far longer than three days.

Producers don’t offer their top-tier wines in a box, and yet absolutely decent boxed wines do exist. You’ll have to do a little research to find ones that match your tastes, but that homework project is its own reward.
 

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