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    It seems the whole world has embraced the ethos of the ant this season, and not the grasshopper. Collectively we are preserving and storing food more than ever before: to maximize summer/early fall produce bounties, to reduce food waste in anticipation of tighter access to foods in coming pandemic months, and to have something productive to do while spending so much time at home. It’s been a big turn for many of us, but in many ways a good one.

    RELATED: The 10 Best Plastic-Free Food Storage Containers for a Greener Kitchen

    Which is why it’s time to talk about vacuum sealers. Built to do just what it sounds like—seal up food for easy long-term storage by removing any air—vacuum sealers can be tremendously useful for food preservation of all kinds. Here are the top 3 reasons you should consider investing in a vacuum sealer now, plus great models to buy now.

    It might seem counterintuitive for a small household, but a vacuum sealer is a terrific investment if you are only one or two at home. Since smaller households tend to go through food at a slower pace, the ability to preserve foods in smaller amounts or to store them over a longer time will help you avoid food spoilage. Whether it is repackaging a partially used wedge of parmesan cheese, breaking down a package of meat into smaller portions for freezing, or re-sealing pantry items like crackers or cereal to keep them from staling, a vacuum sealer is a great thing to have in your kitchen.

    A vacuum sealer does two things: it removes air from the container (usually a bag), then it seals the bag with a heated strip, trapping the vacuum inside. Air is removed with a pump that works by pulling air at a faster rate than ambient air can replace it.

    Pump quality varies, and is in large part the deciding factor on the price of a food vacuum sealer machine. Many edge vacuum sealers have pups with plastic parts. They work alright and can achieve a decent vacuum, but they overheat easily. They have to cool down in between uses, and often can’t withstand heavy use.

    Higher quality food vacuum sealers have heavier-duty pumps made of sturdier parts. They can withstand frequent use and don’t need to cool down between uses.

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    Why Is Vacuum So Great at Preserving Food?

    Contact with oxygen is what deteriorates food, causing spoilage. In the freezer, it causes ice to form, creating freezer burn. Vacuum packing removes almost all of the oxygen from the food container. When there is little oxygen to react with, food stays fresher longer in the pantry and the refrigerator, and won’t get freezer burn in the freezer. That’s really all there is to it.

    It is not possible to remove 100% of the oxygen by vacuum sealing. So vacuum-sealed food doesn’t last forever. But it can remove enough oxygen to greatly extend shelf life. Some estimates are that vacuum sealing extends the life of frozen food by up to 5 years!

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    The Two Types of Food Vacuum Sealers: External and Internal

    There are two main types of food vacuum sealers: edge sealers and chamber vacuum sealers (typically called “chamber vacs”). Both types have advantages and disadvantages.

    Edge sealers, also called external sealers or suction sealers, are the simplest and most common type of automatic vacuum sealer. You simply fill a bag with food, place the bag in the sealer, and begin the sealing process. The vacuum is created inside the bag only, which makes it nearly impossible to seal anything but solid foods (because the pump will suck out liquid as it sucks out air).

    Many edge sealers have options for moist foods and soft foods, allowing you to control the amount of vacuum they pull so as not to draw moisture up into the pump or crush soft food (bread, for example) with too much vacuum. Decreasing the vacuum leaves air in the bag, however, so you may get similar results by just using a Ziploc or other food storage bag for soft/moist foods. One clever workaround is to freeze liquids before vacuum sealing.

    They use special resealable bags that have a small hole through which vacuum is pulled. Handheld sealers are tiny and generally don’t pull a super strong vacuum, but because the bags are reusable, usually for up to 10 times, they’re great for leftovers and sous vide (as opposed to long term freezer or pantry storage).

    In general, edge sealers are the most economical choice, but are sometimes not as well made as chamber vacuums. Most consumer brands–like FoodSaver and Seal-a-Meal–are not designed for heavy use. The pumps overheat easily, so you need to let the machine cool down in between uses. This can be frustrating and time consuming if you’re freezing, say, half a cow or a few bushels of veggies from your garden.

    But for a few steaks or a tray of chicken breasts, they’re great.

    How do you know if your edge sealer has good internal components? Simple: spend more than $300 for it (like this Weston Pro 2300 edge sealer that gets good reviews). But if you’re going to spend that much, you might want to start thinking about a chamber vacuum sealer instead.

    A chamber vac works by creating a vacuum inside a chamber. Because the pressure is equalized inside the entire chamber (and not just inside the bag), a household vacuum sealer can seal liquids. This is great for soups, stocks, leftovers, quick and easy marinades (you can get marinade results in 15-20 minutes in a vacuum sealed container), and many sous vide applications.

    Chamber vacuums pull a stronger vacuum than other portable vacuum sealer.

    Most chamber vacs also have the ability to adjust the vacuum so you can seal soft foods. But you don’t do this with easy-to-use buttons like you can on an edge sealer. Instead, you adjust the actual amount of vacuum you want to pull.

    So while it’s a little trickier to get the vacuum right–and may have a learning curve to figure out–it offers more control over the process. Once you have it set where you want it, you will rarely have to adjust it. Just as with edge sealers, you can keep on eye on the sealing process and stop the vacuum pulling at any time (for example, if food is starting to get crushed, or liquid is bubbling up into the sealing area).

    This packaging machine is used for vacuum packaging with packaging materials having a extremely high gas barrier for the purpose of food preservation. Most of these machines seal the bag containing food in the vacuum chamber. The four types of machines are classified by mechanical faculty: nozzle, chamber, skin, and deep-draw type.

    A Nozzle-Type Vacuum Packaging Machine

    A typical system of this type of machine is shown in Fig. 1. After air in the bag is evacuated through a nozzle, a mouth part of the bag is sealed by heater or impulse system. However, for blocks such as meat and meat products, the bag is mostly clipped with aluminum wire. The two processes of vacuumizing and sealing on most of this type of machines are automatically done, initiated by stepping on a foot swich. Accordingly, although the operation is easier than those of other types of vacuum packaging machines, the degree of vacuum of bags packaged by this type of machine is lower than for others.

    Vacuum packaging is a method of packaging where air from the interior of a package is removed in its entirety immediately prior to sealing the package. This involves placing food products in a plastic film package (or potentially a film package made with other polymer materials), removing air from inside the package with a vacuum pump, and then sealing the package (Church & Parsons, 1995). The materials used for vacuum packaging must be strong enough to withstand the vacuum, flexible enough to form around the food product, and have a very specific level of heat sensitivity. Regarding the heat sensitivity of the material, the material must be sealed during the packaging process, but also suitable for moderate temperatures during cooking (e.g., 75°C). This is especially the situation with the emerging popularity of sous vide cooking of foods.

    Vacuum packaging was invented in the 1950s by a German inventor named Karl Busch, who used the discovery for vacuum packaging meat products. Today, vacuum packaging is common for long duration storage of dry foods like cereals, nuts, cured meats, cheese, and smoked fish, as well as short duration storage of fresh foods like vegetables, meats, and liquids. Vacuum packaging of foods offers several distinct advantages for the food industry, mainly associated with the reduction, or even the potential elimination, of atmospheric oxygen. This slows the rate of oxidative reactions (i.e., lipid oxidation and protein oxidation) and limits the growth of aerobic bacteria and fungi.

    Vacuum packaging refers to the technique of removing air from a pack prior to sealing and it predates the use of gases as a means of food preservation. Its principal purpose is to remove oxygen by pulling the packaging material into intimate contact with the product. It works particularly well for frozen poultry such as turkeys, where the exclusion of air helps to reduce freezer burn, and for fatty fish such as salmon. Hand and semi-automatically operated vacuum packaging chamber machines are available, offering a relatively low cost option (vs. MAP gas packaging), for small- and medium-sized companies such as farms selling their own fresh meat and bacon.

    A significant advantage of vacuum packaging is that the pack volume is virtually the same as the product volume, with no ‘empty’ space inside the pack. However, this also means that products such as joints of meat are of unequal size, making them difficult to display. Dry goods such as pasta (provided the product can withstand the force of the packaging material being pulled around it without breaking up) lend themselves well to vacuum packaging. Products such as ground coffee and dried yeast can be packed in regular brick-shaped packs, thus minimising storage and distribution costs.

    Moderate vacuum packaging (MVP) is a variation of traditional vacuum packaging, used for respiring products such as prepared fruit and vegetables. The product is packed in a rigid airtight container or a pouch and is surrounded by normal air, but at a reduced pressure (around one-third of normal atmospheric pressure). This slows down the metabolism of the product and the growth of spoilage organisms (Laurila and Ahvenainen, 2002).