According to Cooksillustrated.com (subscription required). (Overview) If you pick bushels of berries, buy steaks in bulk, or return from a fishing trip with unexpected bounty, you have more than you can immediately eat. Freeze your stockpile with the notion of feasting all winter, and just one month later you are likely to find it encrusted with fine white crystals. Should you buy a vacuum sealer, a device that promises to keep food fresher in the freezer (“up to five times longer,” swears one brand) by creating an airtight wrap? We tested eight models with prices ranging from $18 to a whopping $470. As food freezes, moisture migrates to the surface and forms ice crystals. Over time, the food dehydrates, discolors, and loses flavor. A good supermarket zipper-lock freezer bag can stave off these problems for a few weeks. But in our tests, food stored in freezer bags was covered with frost after a month. Would vacuum sealers work better for longer-term storage? An Airtight Case We assembled ground coffee, fresh strawberries, 50 pounds of raw steak and chicken breasts, and a fully cooked Thanksgiving dinner, then sealed and froze all of it. Our sealers ranged from handheld models to countertop devices. Most of the latter were about the size of a shoebox; one was larger. Two handheld models seemed dummy-proof: We zipped the food into a plastic bag that has a valve, where we pressed the motorized device to suck out air. All was well until a few coffee grounds or a smear of mashed potatoes got in the way of the zipper. Suddenly, the bags refused to become airtight. Countertop models, which use heat for a tight seal, were more reliable. Most came with both premade bags and rolls made of two layers of plastic already sealed along the sides. We preferred the rolls, which let us create custom-sized bags. To use the roll, you cut a piece to size, insert one open end into the machine to seal it, add the food, and then close the remaining open side, activating both vacuum and seal. All but two of the models required that you press firmly on them while sealing. One cumbersome model required that we press on different corners while simultaneously flattening the bag. Our favorite models all had sensors to detect overflowing liquids. We pulled out the frozen packages after two weeks. We weren’t surprised that the food in two models was coated in ice crystals, the first sign of freezer burn. Those models had failed to form tight seals from the start, especially around the curvy contours of strawberries. Handheld models had formed seemingly airtight seals, but at the two-week mark, bricks of coffee were limp sacks. After one month, our top four continued to hold up. One model was frost-free; tiny air pockets filled with frost surrounded the others. After two months, one wrapped steak remained bright red with just a little frost, while the remaining three contenders showed early-stage freezer burn. It turns out that jagged ice crystals can poke pinholes through plastic, letting air and moisture seep in. At 0.05 mm thick, the winning model’s bags were 0.02 mm thicker than the runner-up bags, and 0.03 mm thicker than a standard zipper-lock bag. Small as it may seem, that extra protective bulk made a lot of difference and pushed our winner to the top. It's a Wrap Are vacuum sealers economical? It depends how much food you freeze. Each vacuum sealer works only with its own plastic, and cheaper models didn’t necessarily come with cheaper plastic. A quart bag costs 26 cents with the $470 model and nearly three times that with the $30 model. The others averaged 45 to 55 cents per bag or foot. Without a doubt, our winner did the best job of getting an airtight seal and keeping food fresh in the freezer. But it requires lots of counter space, a little muscle, and a very large budget. For most people, our runner-up is a better choice. It was the easiest to use and kept a respectable seal after a month. It’s our Best Buy. (Comparison Chart) HIGHLY RECOMMENDED \t Pragotrade Vacuum Sealer Pro 2300 The Rolls-Royce of vacuum sealers. It was the only model with bags strong enough to keep frozen food perfectly sealed and frost-free after two months. But it was expensive, large, and heavy (26.5 pounds), and you must press on the lid during vacuuming. Only for the devoted freezer-owner. ★\t ★\t ★\t ★\t ★\t$469.95 RECOMMENDED \t FoodSaver V2240 Vacuum Sealer Kit Intuitive and easy to use, this hands-free model was much smaller and lighter than our heavyweight winner, sealing food tightly and quickly. After a month, tiny air pockets formed around food, but packages stayed sealed with minimal frost. At two months: early signs of freezer burn. ★\t ★\t ★\t ★\t ★\t$99.99 RECOMMENDED \t Rival Seal-A-Meal VS107 Food Saver with Hold Release This relatively lightweight model was harder to use than the FoodSaver V2240; we had to push the lid during vacuuming, but it sealed as tightly. After a month, we saw tiny air pockets and frost, but packages stayed sealed. At two months: early signs of freezer burn. ★\t ★\t ★\t ★\t$63.02 RECOMMENDED WITH RESERVATIONS FoodSaver V3840 Vacuum Sealer Kit This model sealed as tightly as the other FoodSaver model, but its bells and whistles didn't justify the extra $73. Sitting vertically to save space, it's still wider than other models. The sealing slot is too narrow, and we found no difference between "dry" and "moist" food functions. ★\t ★\t ★\t$173.97 NOT RECOMMENDED \t Reynolds Handi-Vac Vacuum Sealer As long as food didn't get caught in the zipper, this handheld device made a tight seal at first. But after one months, bags of coffee that had been brick-hard were loose, and other foods were covered in frost. ★\t ★\t ★\t ★\t$18.35 NOT RECOMMENDED \t Zip Vac Portable Food Storage System This handheld model sealed tightly, but broke after just six uses. A backup unit had similar problems. If food got near the zipper, it wouldn't seal. After a month in the freezer, bags lost their seal. And while the device is cheap, its bags are not. ★\t ★\t ★\t ★\t$29.99 NOT RECOMMENDED \t Oliso Frisper Vacuum Sealer This model works by puncturing a hole in a reusable bag to draw out air, then heat-sealing around the hole. But its vacuum was too weak for a tight seal, especially around curvy strawberries, and it was so loud we wanted earplugs. ★\t ★\t ★\t$59.99 NOT RECOMMENDED \t Deni Freshlock Turbo II Vacuum Sealer Between pressing on different corners and having to seal three sides of a roll to make a bag, this model is a hassle. Bags felt cheap, the thin melting wire almost broke after three uses, and its weak vacuum struggled mightily. ★\t ★\t$97.99