The fastest way: use a FoodSaver or similar vacuum sealer with a jar attachment

Most home vacuum sealers sold for food storage come with a small plastic tube attachment designed to fit mason jar lids. You place the tube over the lid's center, run the sealer for a few seconds, and the machine pulls air out through the tube. The lid seals as the air leaves. This takes about 30 seconds per jar and works reliably with quart and pint jars.

The attachment is usually included with mid-range and higher-end models — check your sealer's box before buying. If your sealer did not come with one, you can buy a universal jar attachment separately for $10 to $20. The tube fits most standard mason jar lids, though wide-mouth jars sometimes need a different adapter.

This method works best with dry goods: flour, sugar, coffee, nuts, dried fruit, and grains. It is less reliable for liquids or foods with high moisture because condensation can interfere with the seal.

Key Takeaways

  • A vacuum sealer with a jar attachment pulls air directly from the jar through a plastic tube, creating a seal in seconds without boiling water.
  • Dry goods like flour, sugar, and coffee seal most reliably; wet foods and liquids are harder to seal this way because moisture interferes with the process.
  • The jar attachment is usually included with mid-range sealers but sold separately for basic models, costing $10 to $20 if you need to buy it alone.
  • Standard mason jars work with most attachments, though wide-mouth jars may need a different adapter depending on your sealer brand.
  • A sealed jar stays fresh longer than an open one, but vacuum sealing does not replace pressure canning for foods that need heat processing to be shelf-stable.

What you need before you start

You will need a vacuum sealer with a jar attachment, clean mason jars with lids and bands, and the food you want to store. The jars should be completely dry inside — any moisture left from washing will weaken the seal. Dry them with a clean cloth or let them air-dry for at least an hour.

The lids must be new or in good condition. If a lid has dents, rust, or a damaged rubber gasket, it will not seal properly. The band (the metal ring) does not have to be new, but it should be clean and free of corrosion. Wipe both the lid and the jar rim with a dry cloth before sealing.

Step-by-step: sealing a jar with your vacuum sealer

Place the lid on the jar without the band. The lid should sit flat on the rim but not be screwed down. Put the jar on a flat, stable surface — do not hold it in your hand while sealing, because the jar can shift and break the seal.

Fit the plastic tube attachment over the center of the lid. Push it straight down until it sits firmly. Turn on your sealer and select the jar setting if your model has one. The machine will pull air for 5 to 10 seconds, then stop automatically. You will hear a slight hiss as air leaves the jar.

Remove the tube and check the lid. It should be slightly concave (curved inward) in the center. If it is still flat or bulging outward, the seal did not hold — try again with a new lid. Once the seal is confirmed, screw the band on hand-tight. Do not over-tighten it.

Let the jar sit for 24 hours before moving it. The seal will strengthen as it cools. After that, you can store it in a cool, dry place. A sealed jar will keep dry goods fresh for several months longer than an unsealed one.

Why this method works better than boiling water

Boiling water (the traditional canning method) heats the jar and its contents, which kills bacteria and creates a seal as the jar cools. Vacuum sealing removes oxygen instead, which slows the growth of mold and bacteria but does not kill them. For shelf-stable storage without refrigeration, boiling is safer for most foods.

Vacuum sealing is faster and does not require heat, so it is better for foods that should not be heated — like nuts, coffee, or dried herbs. It also works for foods you plan to refrigerate or freeze. The trade-off is that vacuum-sealed jars are not shelf-stable the way canned jars are, and they should be kept cool.

Common problems and how to fix them

The seal did not hold. This usually means the lid was wet, the jar rim was dirty, or the tube did not sit firmly on the lid. Wipe the jar rim and lid with a dry cloth, use a new lid, and make sure the tube is pushed straight down with no gap.

The lid is bulging outward. The jar may have been sealed with air still inside, or the food inside is releasing gas. Do not use this jar. Empty it, clean the lid and jar, and try again with a new lid. If it happens repeatedly, the food itself may be the problem — some foods ferment or release gas over time.

The attachment does not fit your jar. Wide-mouth jars and some older mason jar brands have different lid sizes. Check your sealer's manual for compatible sizes, or buy a universal adapter that fits multiple lid diameters. Some brands sell wide-mouth attachments separately.

The tube keeps popping off. The lid may be slightly warped or the tube may be worn. Try a new lid first. If the tube itself is loose or cracked, it may need to be replaced — contact the sealer's manufacturer for a replacement part.

What foods seal well and what does not

Dry goods seal reliably: flour, sugar, salt, coffee, tea, nuts, seeds, dried fruit, grains, and pasta. These have no moisture to interfere with the seal and will stay fresh much longer in a sealed jar than in an open container.

Foods with high moisture or that release gas do not seal well this way. Honey, oils, and other liquids can seep into the lid's gasket and prevent a tight seal. Fermented foods like sauerkraut or kimchi release gas over time and can break the seal. Soft foods like bread or cookies will be crushed by the vacuum.

If you want to preserve wet foods or foods that need heat processing, use the boiling-water canning method instead. Vacuum sealing is best for dry goods you plan to use within a few months, or for foods you will keep in the refrigerator or freezer.

Frequently Asked Questions

Can I vacuum seal a mason jar without a special attachment?

Not with a standard vacuum sealer. The sealer's bag-sealing strip is designed for flat plastic, not curved jar lids. You need the tube attachment to pull air directly from the jar. Some people use a straw and their mouth to manually remove air, but this is slower and less reliable than using the attachment.

How long will food stay fresh in a vacuum-sealed jar?

Dry goods like flour and sugar typically stay fresh for 6 to 12 months in a sealed jar, compared to 2 to 3 months in an open container. The exact time depends on the food, storage temperature, and light exposure. Keep sealed jars in a cool, dark place for the longest shelf life.

Is vacuum sealing safe for long-term storage without refrigeration?

Vacuum sealing removes oxygen but does not kill bacteria or prevent all spoilage. It is safe for dry goods stored at room temperature, but not for foods that require heat processing to be shelf-stable, like low-acid vegetables or meats. For those foods, use pressure canning instead.

Can I reuse mason jar lids after vacuum sealing?

No. Once a lid has been vacuum sealed, the gasket is compressed and will not seal again reliably. You must use a new lid each time. The band and jar can be reused indefinitely as long as they are clean and undamaged.

What if my vacuum sealer does not have a jar attachment?

You can buy a universal jar attachment separately for $10 to $20, or you can upgrade to a sealer model that includes one. Check the product listing or manual to confirm the attachment is compatible with your sealer brand before buying.