The fastest way: use a straw and your mouth

You can vacuum seal a ziplock bag by hand using nothing but a drinking straw. Fill the bag with what you want to store, seal it almost all the way, leaving a gap about the size of a quarter. Slide a straw into the gap, press the bag flat around the straw, then suck the air out through the straw. Once the air is gone, pull the straw out quickly and press the remaining gap shut with your fingers. The seal holds because the pressure inside drops below atmospheric pressure.

This method works best for dry goods, leftovers, and items you plan to use within a few weeks. It is not airtight enough for long-term freezer storage or items that need true vacuum conditions, but it removes enough air to slow oxidation and freezer burn. The whole process takes under a minute once you get the motion down.

Key Takeaways

  • A straw and your mouth can remove most air from a ziplock bag in under a minute, and the seal holds for several weeks in the refrigerator or freezer.
  • Boiling water creates steam that pushes air out of the bag, and the seal tightens as the steam cools — this works well for marinating and sous vide cooking.
  • A handheld vacuum sealer designed for ziplock bags costs between $20 and $60 and removes air more completely than mouth or water methods.
  • The straw method works best for dry foods and cooked leftovers; the water displacement method works better for raw meat and items that need longer storage.

Using boiling water to displace air

Fill your ziplock bag, seal it almost completely, then lower it into a pot of boiling water. Keep the opening above the water line. As steam enters the bag, it pushes the air out. When the bag is mostly full of steam, quickly seal it the rest of the way and pull it out of the water. As the steam cools inside the sealed bag, it contracts and creates a partial vacuum.

This method creates a tighter seal than the straw method because the cooling steam pulls the bag walls inward. It works especially well for marinating meat — the vacuum helps the marinade penetrate faster. It also works for sous vide cooking, where you need the bag to stay sealed in hot water. The downside is that the bag gets wet and takes a few minutes to dry.

Be careful not to submerge the opening. If water gets inside the bag, your food is ruined. Hold the bag by the top corner and lower it slowly, keeping the seal area above the waterline the entire time.

Handheld vacuum sealers for ziplock bags

A handheld vacuum sealer is a small electric device that sucks air out of a ziplock bag through a valve or port. You place the bag opening against the port, press a button, and the machine removes the air and seals the bag in about 10 seconds. Most models cost between $20 and $60 and run on batteries or USB power.

These machines remove more air than the straw or water methods, which means food stays fresher longer. They work on any ziplock bag and are fast enough to use every time you store something. The trade-off is that you have to buy and charge the device, and some models are flimsy or stop working after a few months of use.

Look for models with a sealing strip that is at least 3 inches wide — this seals the bag more reliably than narrow strips. Check reviews on the specific model before buying, because quality varies widely in this price range. Some people report that cheaper models fail after a few dozen uses.

What to store in vacuum-sealed ziplock bags

Vacuum sealing works best for dry goods that do not need to breathe: flour, sugar, coffee, nuts, crackers, and cereal. It also works well for cooked leftovers, marinated meat before cooking, and items you plan to freeze. The reduced air slows the growth of mold and bacteria, and it prevents freezer burn on frozen items.

Avoid vacuum sealing raw vegetables with high water content, like lettuce or tomatoes, because the pressure crushes them. Do not seal anything still hot — let it cool to room temperature first, or steam will escape and break the seal. Soft breads and pastries also get crushed by the vacuum, so store those in regular sealed bags instead.

For long-term freezer storage of more than three months, a true vacuum sealer machine (the kind that heats and seals a special bag) works better than any ziplock method. Ziplock bags, even when vacuum sealed by hand, are not designed for storage longer than a few months.

Why vacuum sealing slows spoilage

Food spoils through two main processes: oxidation (when oxygen reacts with fats and proteins) and microbial growth (when bacteria and mold multiply). Removing air slows both. Without oxygen, oxidation nearly stops, which is why frozen food in a vacuum-sealed bag stays fresher longer than food in a regular bag.

Removing air does not stop bacteria or mold completely — it only slows them down. Vacuum sealing is not a substitute for refrigeration or freezing. A vacuum-sealed bag left on the counter at room temperature will still spoil, just slightly slower than an open bag. The real protection comes from cold temperature; the vacuum seal just extends how long the cold keeps the food good.

Common mistakes to avoid

The most common mistake is sealing the bag too early. If you seal it before removing enough air, the remaining air expands and breaks the seal within hours. Always remove as much air as possible before you seal the final gap.

Another mistake is using bags that are too thin or old. Ziplock bags degrade over time, especially if they have been in a hot cabinet for years. Old bags crack or leak when you try to vacuum seal them. Buy fresh bags if you are having trouble getting a seal to hold.

Do not vacuum seal anything wet or damp unless you are using the boiling water method. Moisture on the bag walls prevents the seal from sticking. Dry the outside of the bag with a paper towel before sealing, and make sure the inside surfaces around the seal are dry too.

Frequently Asked Questions

How long does a vacuum-sealed ziplock bag stay sealed?

A seal made with the straw method usually holds for several weeks in the refrigerator and a few months in the freezer. The boiling water method creates a tighter seal that can last longer. Over time, the seal weakens as the bag material relaxes, so do not expect it to hold for more than a few months even in the freezer.

Can I reuse a ziplock bag after vacuum sealing it?

Yes, if the seal did not damage the bag. Wash it, dry it completely, and seal it again. After a few uses the bag material weakens and may not seal as well. Most people use each bag two or three times before throwing it away.

Does vacuum sealing work for freezing meat?

Yes, it works very well. Vacuum sealing prevents freezer burn and keeps meat fresh-tasting for several months. Use the boiling water method or a handheld sealer for the best results, since these remove more air than the straw method.

What is the difference between vacuum sealing a ziplock bag and using a vacuum sealer machine?

A vacuum sealer machine uses a heating element to seal a special bag after removing air, creating an airtight seal that lasts for years. Hand methods on ziplock bags remove air but create a weaker seal that lasts weeks to months. Machines are better for long-term storage; hand methods are fine for short-term use.

Can I vacuum seal liquids in a ziplock bag?

Not with the straw or handheld sealer methods — the liquid will get sucked into the machine or come up through the straw. The boiling water method works for liquids because the steam pushes the liquid down as it enters. Freeze liquids solid first, then vacuum seal them, and they will stay sealed as they thaw.