The Best Way To Keep Open Wine Fresh
Not all wine preservers are rubbery corks that operate with vacuum pumps. Preservation is a contentious issue in the wine community, but after 13 hours of research and testing, interviews with food writers and multiple James Beard-nominated/winning sommeliers, plus a taste test with two certified wine experts, we recommend Private Preserve as the best way to keep an open bottle of wine fresh. A mixture of inert gases found naturally in the atmosphere that’s denser than air, it creates a protective blanket between the leftover wine and the oxygen in the bottle, which you then seal in with the bottle’s existing cork. It beat out seven other preservation methods in head-to-head testing, best maintaining the flavor and aroma of wine over a five-day period. It’s the only tool we tried that beat just recorking and refrigerating a half-full bottle of wine.
Private Preserve comes in a can that resembles WD-40. A few spritzes create a protective barrier between the top of your leftover wine and the oxygen that would otherwise destroy it. The $9 can feels empty, which may be off-putting to some, but the gas inside can be used to save up to 120 bottles of wine. It’s a totally safe method that doesn’t have any effect on taste; it’s even FDA approved.
Table of contents
Who should buy this? | How we picked and tested | Our pick | Testing results | The winemaking process | Flaws but not dealbreakers | A runner-up | The fridge | What about Coravin? | Competition | Wrapping it up
Who should buy this?
There’s a big debate among wine professionals about the efficacy of specific preservation systems, but one thing is clear: if you’re going to be drinking wine at home, it’s not a bad idea to have a good wine saver on hand. An effective model will allow you to put the bottle down on Monday and pick it back up on Friday, and it will taste just about the same as it did when you opened it up.
Whether you choose to get a wine preserver or not, make sure you put the bottle in the fridge. In our tests, we found that plain old refrigeration was more effective than most preservation systems in keeping bouquet intact and reducing oxidation. (Read more in The fridge.) But our pick plus refrigeration will really help preserve the aromas and flavor of a half-emptied bottle of wine.
How we picked and tested
A good wine preservation system keeps an open bottle of wine tasting fresh for days, or longer by keeping oxygen away from the wine. There are several ways to achieve this. The vacuum sealer-style involves a stopper that fits into the mouth of an open bottle and a pump that pulls out the air inside. Others create a barrier between the oxygen and the juice without actually extracting any air. While one can’t expect a bottle to last forever, we found five days to be a reasonable expectation, and we ran our tests based on that figure.
Like any other kitchen gadget, we took ease of use and cost into consideration along with efficacy. Even though some of the of the systems were a little funky in their setup, none of them were difficult to use. With the exception of one outlier, all of the contenders we considered were $25 or less, and most were closer to $10. Systems that allow multiple bottles to be preserved at once have an advantage over those that don’t.
We began our research by finding the top-selling wine preservation systems across the internet. Then we searched out tests that others have completed. Cook’s Illustrated (subscription required), WIRED, and numerous wine publications have run tests over the years (some in the very recent past) that were helpful in us reaching our conclusions.
We also spoke to winemakers and sommeliers about what they use and what they recommend for the general public. We got input from experts such as Jill Zimorski, wine director at the Hotel Jerome and formerly of Bryan Voltaggio’s Volt in Frederick, Maryland; Jordan Salcito, beverage director of David Chang’s Momofuku restaurant group, and formerly of Eleven Madison Park, where she was part of a James Beard Award-winning beverage team; James Beard-nominated sommelier Michael McCaulley, wine director and partner at Philadelphia’s Tria; and Tracy Howard, senior editor at Imbibe Magazine.
There were three main product recommendations from the experts: Vacu Vin, Private Preserve, and Coravin. Many use one of the first two options in their bars and at home, while the $300 Coravin has become popular lately in wine programs as a way of pouring single glasses of expensive wines that otherwise would have to be sold by the bottle. Almost all of the experts also recommended using the refrigerator as a way to make an open bottle of wine last even longer.
To weed out the least-effective vacuum sealers, we used two distinct tests. In the first test, we filled each bottle with 100 grams of mini marshmallows, pumped the vacuum seals to expand the marshmallows in size, kept them sealed for 24 hours, and watched to find out in which bottles the marshmallows would shrink back to normal size first, which would indicate a leaking vacuum seal.
In all five testers, the marshmallows expanded to some degree, showing a working vacuum, but the marshmallows began to return to their original size at varying rates. After a day had passed, we opened all the bottles; we listened to hear if there was any “hiss” indicating air was flowing in.
When we reopened the vacuum sealers, we found that three of the models—the Vacu Vin Wine Saver ($7), OXO Steel Vacuum Wine Preserver ($15), and VinoTru Wine Saver ($12)—had extra-shriveled marshmallows, while the Wine Doctor Barware Kit ($50) and Sharkk Wine Bottle Stopper ($9) did not.
We talked to our in-house physicist, John Holecek, about what was happening, and he speculated that the models with shriveled marshmallows had expanded enough that the air pockets within the marshmallows had burst, causing the sweets to collapse. The test didn’t actually reveal which vacuum had stayed intact for the longest time, but it did show which of the five vacuum pumps had the strongest initial vacuum.
So we decided on a second test, this one involving water. We pumped empty bottles, leaving them sealed for 24 hours, and then opened them upside down with the bottle mouth submerged in a bucket of water. We repeated this five times, each time measuring the volume of water that was sucked up. The more water in the bottle, the stronger the vacuum. Averaging these tests out, we found the same three preservation systems to be the most effective. We moved the OXO, the Vacu Vin, and the VinoTru through to the next round of testing.
Once we had determined our top five finalists—the three vacuum savers and two others—we set up a taste test for them along with three other commonly-used preservation methods that didn’t require special equipment: one bottle was simply recorked at room temperature; one bottle was recorked and then placed in the fridge; and one half bottle was emptied into a smaller container (a one-pint Ball Mason Jar), which would theoretically reduce the amount of oxygen (and thus oxidation) in the container.
Five bottles of 2009 Di Majo Norante Ramitello, an Italian red, were purchased for testing. This affordable vintage was recommended to us by one of our taste testers, Tommy Lombardo, as a bottle with a tannic structure that would help show signs of breakdown well. Each bottle was fully emptied into a pitcher, and split in half by mass into separate bottles.
Once filled, all the bottles were left to sit for five days; the unrefrigerated bottles were kept together in a shady area of a kitchen that averaged around 70°F. At the end of that period, the wine was tasted in a blind test by two wine professionals. Tony Rials is the bartender at Mike A @ The Hotel Lafayette in Buffalo, NY, and a certified sommelier. Tommy Lombardo serves as general manager and beverage director of Ristorante Lombardo, also located in Buffalo. He holds an advanced certificate from the International Wine Center. The preserved bottles were compared against a fresh bottle of the wine, with Rials and Lombardo ultimately finding the system that left the wine tasting closest to the original.
Scott Farmer came up with Private Preserve when he was working in a winery where inert gases were pumped into wine to keep it fresh. He then developed the formula for the spray, which includes nitrogen, carbon dioxide, and argon. These are three of the four most common elements in the air we breathe everyday. (Naturally, oxygen is the one missing from that list.) It makes sense that these gases would be used to save wine.
Imbibe’s Tracy Howard told us, “Argon is what a lot of the winemakers use to top off their barrels. It’s heavier than oxygen, so it creates a really dense layer of gas on type of the wine, forcing all of the air to go above it, so you’re not having that contact.” (Picture an invisible, tasteless blanket between the liquid and oxygen.)
The pressurized steel can of Private Preserve feels empty even when it’s full. That’s actually listed on the busy label so customers don’t feel ripped off. It contains 0.29 ounces/8.2 grams of gas, and they claim that’s good for preserving at least 120 standard 750-mL bottles of wine. (For “each 750-mL increase in size,” they ask that you double the procedure in order to blanket the wider surface area in larger bottles; if you’re regularly recorking magnums, you’ll use up more gas.) The gas itself is odorless and doesn’t add any off-flavors to the wine.
Unlike some of the systems we tested, Private Preserve does require just a little bit of effort to work correctly. The process, as outlined on the back of the can, is as follows: insert one of two included straws into the nozzle, put the top of the tube halfway down the neck of the bottle, against the glass, place the cork over the opening, spray for half a second, followed by three short bursts, and then pull the straw as you recork. In its first attempt, Cook’s Illustrated said “the straw inside the canister flew off the sprayer head and into the wine.” We didn’t have this issue at all, but can see how someone might in early uses.
Private Preserve is very cost-effective. Assuming it provides the full 120 uses, you’re looking at about 7.5 cents per seal, based on the Amazon price at the time of publication. For less than than the price of a bottle of decent wine, you can save 120 of them. According to the package, it can actually be used to save any number of foods and drinks that are affected by air—cognac, bourbon, tequila, herbs, and olive oil, just to name a few. Yes, the vacuum preservers are one-time investments, but they just don’t work as well.
Because Private Preserve doesn’t remove anything from the bottle the way that vacuum pumps do and uses the original cork to seal it back up, there’s no issue with aromatics being pulled out or faulty seals letting oxygen in. Tria’s McCaulley told us “if you use inert gas, you’re going to get a more perfect seal.”
In a June 2013 test, Wired found Private Preserve to be the best system for preserving wine, scoring it a 9 out of 10. According to author Christopher Null, who’s “been writing about wine for more than a decade,” and his wife, “a wine industry professional and seasoned taster,” “if you do use Private Preserve correctly, it really does seem to do the trick. Blind tastes of wines preserved for two days and seven days with the product earned some of the highest marks in my comparison. I couldn’t tell much of a difference between a fresh bottle of wine and one preserved with Private Preserve for a week.”
The July 2008 issue of Decanter magazine featured a comparison of many of the popular preservation methods, and author Beverly Blanning also named Private Preserve her favorite. Her ultimate conclusion was “the Private Preserve gas cylinder came out as the best way to keep our three types of wine fresher for longer.”
In its literature, the company even claims to have maintained the flavor in bottles for as long as four years. Of its 60 Amazon reviews, there’s a 4.7-star average rating with 51 people awarding 5 stars.
Private Preserve also packages its product under the Wine Enthusiast brand, so if you happen to see that for a lower price, go for it.
In our taste test, Tony Rials and Tommy Lombardo agreed that the wine preserved with the Private Preserve tasted the closest to the fresh bottle. Using descriptions such as “no faults” and “terrific,” the two said the intensity of the flavor was maintained and the aroma was clear. While the tannins were slightly diminished, it’s impossible to eliminate every bit of degradation.
Their least favorite sample was the wine that was simply recorked and left to sit in room temperature. The two said the tannins had softened, the acid was out of balance—an obvious indicator that bacteria is chomping away at the wine—and the flavor was more muted than the others.
It’s worth noting that our testers actually preferred the particular bottle of wine we chose once it had oxidized a bit, as it had under the vacuum seal. Wine is a multifaceted thing. They looked past this, though, to determine which tasted the closest to fresh.
The winemaking process
One might wonder how wine stays good in an unopened bottle on the shelf, as it’s never filled to the absolute top of the bottle; there’s always some air in there. We spoke to Jonathan Oakes of Leonard Oakes Estate Winery in Medina, New York, along Lake Ontario, to better the process of bottling wine.
Several methods are used to help prevent oxidization in the bottle. One of the most prevalent is the addition of sulfur compounds during the winemaking process. Serving as both antioxidants and antimicrobials, these compounds are added as powdered material throughout the production process. “Unless you use too much sulfur, it doesn’t affect the flavor,” Oakes told us. Some wineries use vacuums to suck out the air, and some will fill the bottles with nitrogen or argon: sound familiar?
Flaws but not dealbreakers
In its advice column “Ask Dr. Vinny,” Wine Spectator stated “I personally haven’t had much luck with inert gas—there’s something about working with an invisible product that makes me feeling [sic] like I’m doing it wrong. But I appreciate the science behind it and know many wine professionals and restaurants that use that method.” The biggest problem with Private Preserve is it’s close to impossible to tell if you’re doing it right, as there’s no feedback of any kind. Frankly, it’s not as satisfying as using one of the pumps, even if it’s more effective. You have to follow the instructions closely and have faith that it’s working correctly.
Along the same lines, some may consider the feeling of an empty can to be a drawback. This is only a psychological barrier, but that’s not to be overlooked. It’s certainly a little disconcerting the first time you lift up the can. The can is actually empty when it stops hissing when you press the nozzle.
The folks at Cook’s Illustrated were not fans of Private Preserve in their testing, as mentioned above. They filed it in the “not recommended” category. Although we greatly respect their opinion, our research and testing results don’t match what they found.
To understand Air Cork, picture a balloon attached to a pump by a short length of tube. In this case, the pump happens to be shaped like a bunch of grapes. You lower the deflated balloon into your bottle of wine, and then pump to inflate it, creating a barrier between the oxygen and the wine. Each balloon can be used 80 times before having to be replaced for $5.
The balloon is designed to touch the surface of the wine without affecting its flavor, and is up to code with the FDA. We found the system a little cumbersome, as it leaves a somewhat gimmicky looking accessory hanging from the bottle. We don’t like that for the $25 price, only one bottle can be preserved at once. It did a good job of keeping the wine fresh though; again, we’d suggest refrigeration to boost the results. Note that this was the least favorite system in WIRED’s guide.
One piece of advice that come up again and again in our research and interviews is that no matter how it’s preserved, put open wine in the fridge. “You basically want to cut two things: you want to cut temperature, and you want to cut oxygen exposure,” Tria’s Michael McCaulley told us. “If I know it’s going to be a long period of time, I’ll keep the red wine cool in the fridge, and then once we get around to having it, I’ll pop it out an hour before and let it sit.” Quoting the chairman of the department of viticulture and enology at the University of California, Davis, Martha Stewart says in a 2010 advice column, “refrigeration is a good idea – it will slow oxidation and curb the organisms that can spoil the wine.”
According to Jill Zimorski at Hotel Jerome, “anything will keep better, closed up (whether gassed or not) and put in your fridge where it’s cool and dark.” Momofuku’s Jordan Salcito told us the same thing. “It may sound overly simple, but just recorking a bottle and storing it in the fridge can elongate a bottle’s lifespan for a day or two.” The technique used by Imbibe’s Tracy Howard is simply to pour any leftover wine into an empty half-bottle, and then pop it in fridge. “Refrigeration exists for a reason, and that’s really to preserve things.” It’s better to stand the bottle straight up, as there’s less surface area for contact between the wine and air.
Over at Serious Eats, cocktail science writer and author of Craft Cocktails at Home: Offbeat Techniques, Contemporary Crowd-Pleasers, and Classics Hacked with Science Kevin Liu just ran some tests on the best way to store vermouth — fortified wine — and his results were just about identical to ours. He concluded that “Refrigeration works pretty darned well,” because after a month, he “couldn’t tell the difference between fresh, unopened vermouth and a half-empty bottle that had been sitting in the fridge.” Additionally, “Inert gas works better than rebottling.” His overall conclusion: “Based on these experiments, I’ll be storing my vermouth in the fridge without inert gas or at room temp with inert gas if I don’t have fridge space…If I had to store vermouth for longer than a month or two, I would purge the vermouth with inert gas and leave it in the fridge if possible.” We still say to do both.
What about Coravin?
You may have heard of the Coravin 1000 Wine Access System, a relatively new tool in the wine preservation arsenal. This $300 accessory has earned rave reviews and is being used in high-end wine programs across the country. Wired calls it “top-notch preservation,” and Cook’s Illustrated says that “tasters found the wines we poured from it, which had been open for a month, just as good as wine from freshly opened bottles (and we are continuing to test).”
The Coravin works by injecting a long needle through the cork, pulling out the wine, and replacing the space left behind with tasteless pressurized argon gas. Once you’ve poured a glass, the Coravin can be removed and used on a different bottle. The argon capsules cost $11 each–or a little bit less if you buy in bulk—and the company says, “Each Coravin Capsule will allow you to pour up to fifteen 5 ounce glasses of wine,” or about three standard bottles.
We weren’t able to include the Coravin in our original tests because it was recalled in June 2014 due to 13 reports that bottles had broken under pressure, injuring at least one person. The company now includes a neoprene sleeve for the bottle in the package, which should prevent injuries in case the glass does break.
We put Coravin up against Private Preserve and invited wine expert Tommy Lombardo back to taste test. The Coravin was used to remove 375mL of one bottle of wine, and we poured out the same volume from another, before spraying in the Private Preserve and recorking. We kept these two bottles, along with a third control bottle, in the same location in our test kitchen for five days before we popped them open.
We presented Tommy with a glass of the fresh wine, as well as glasses labeled “A” and “B,” each filled with one of the preserved wines. He told us that while the differences were very, very small between the two, glass B tasted more like the fresh bottle than glass A, correctly guessing that B had been saved with the Coravin. According to Tommy, the Private Preserve wine had opened up just a bit more, but he reiterated that the two glasses tasted very similar to one another—pretty amazing considering that Private Preserve is so much cheaper.
The big $290 difference between the Coravin and Private Preserve spray is that the Coravin’s needle extraction preserves a more sealed environment, which means wines can last even longer than five days. Several of the sommeliers we spoke to even said the Coravin kept bottles fresh for months. For serious wine drinkers who buy expensive bottles and want to savor them over time, it’s a great solution. However, the majority of casual drinkers will be better off with Private Preserve, which costs so much less but works nearly as well, at least for short-term home use.
There are two main complaints about vacuum pumps not present when it comes to inert gas: they don’t form perfect, airtight seals, and they strip out the aromatic elements of the wine. Tracy Howard told us, “as you’re trying to pump the oxygen out and create a vacuum, you’re never going to get a perfect vacuum. There are seal issues with all of the ones I’ve played around with. Secondly, as you’re pumping, you’re stripping a lot of the aromatics from a bottle of wine. It’s been my experience that the next day you’ll pour it in your glass and swirl and it around and it might not taste bad, but it smells kind of flat.”
We don’t consider it great, but the best vacuum pump system of the three we tested was the VinoTru Wine Saver. Like most of the vacuums we tested, it has two distinct pieces. There’s the 5.75” long pump, and the plastic and rubber cap that fits into the bottle. This set actually includes two of those stoppers, meaning you can preserve two bottles of wine at once. Each has a small black disk surrounded by the numbers 1 through 31 to indicate when the bottle was sealed.
Our taste testers found this system to be closer to the fresh bottle than either OXO’s Steel Vacuum Wine Preserver or Vacu Vin’s Wine Saver. They said the tannins had softened a little, but they were still present.
A 1988 article from The Wall Street Journal by Susan Hauser entitled “Testing the Vacu-Vin” quotes Matt Kramer of Wine Spectator as well as scientific tests. Using a pressure gauge, the researchers found that the pump only “removes about 65% to 70% of the air, and then the air almost immediately begins to leak back into the bottle through the seal of the Vacu-Vin rubber stopper.” After an hour and a half, “the pressure in the bottle had already diminished by about 15%.” Kramer’s concludes, “the Vacu-Vin is no shield against the deteriorating effects of oxidation, and may even purge some of the volatile esters, the flavor and aroma components.”
Six years later, in a 1994 Wine Spectator piece (subscription required), Kramer goes on to say, in no uncertain terms, “Vacu-Vin doesn’t work. It never has.” He concludes that the wine deteriorates quickly, and “just recorking the wine worked equally as well — or as badly.” The title of the piece really sums it up well: “A Giant Sucking Sound — And That’s All.”
While OXO often makes great products, its OXO Steel Vacuum Wine Preserver didn’t live up to our expectations. It was the only one of the vacuum savers that had a totally broken seal when we opened the bottles for our taste test; there was no audible rush of air when it was removed. Our tasters found that over five days, the tannins in the wine had decreased, and the wine had lost flavor.
We also declined to test a number of vacuum pumps based on low Amazon ratings. These include Waring Pro’s WP55 Cordless Wine Preserver ($19), Brookstone’s Automatic Wine Preserver ($15), Metrokane’s Houdini Wine Preserver ($12), Rabbit’s Electric Wine Preserver ($36), and Metrokane’s V-Gauge ($15).
While we would’ve liked to include the Hummingbird Ultra Wine Saver Kit ($40) from True Fabrications based on a recommendation from Tracy Howard at Imbibe, we were not able to do so because the product has been discontinued.
Based on poor reviews by both Cook’s Illustrated and Wired, we didn’t test the Savino Wine Saving Carafe ($50). While it has a relatively high 4.1-star rating on Amazon, CI reported “after one week, tasters found that both white and red wines stored in the Savino lost too much of their character and flavor,” and Wired rated it with a 5, based on inconsistent performance, many pieces to clean, and the high price.
Pulltex has a new system called AntiOx, which doesn’t seem to be available in the U.S. at the time of this article’s publication. A cap that just fits onto the head of a bottle without any sort of vacuum sealing, it offers “effective filter performance,” stopping the reaction inside the bottle, according to its marketing materials. The oxygen isn’t pulled out, however, so it’s not clear how this system would actually work.
While it may be cool for camping or sneaking into concerts, the Platypus PlatyPreserve Wine Preservation System ($10) isn’t the right choice for home use. An airtight bag, it holds your wine with a screw-on cap, holding up to 800 mL, which is just a bit more than the volume of the average bottle of wine.
The only other wine spray can wine preserver we came across was VineyardFresh ($15), but with no big reviews behind it, a higher price, and the promise of saving only 50 bottles, it doesn’t warrant a pick over Private Preserve.
Wrapping it up
If you’re not going to finish your bottle of wine in one sitting, the best way to preserve it is to spray it with Private Preserve and then put it in the fridge. If it’s a red, take it out about an hour or so before you’re ready to serve it and you’ll be good to go. It’s cheap, easy, and will best maintain the flavor of the wine.
Originally published: December 15, 2014