You want to extend the life of your food, and vacuum sealing canning jars is a fantastic method. Learning how to vacuum seal canning jars is easier than you might think, and it opens up a world of food storage possibilities beyond traditional canning. This guide will walk you through the simple tools and steps needed to get started. You’ll be preserving dry goods, leftovers, and more in no time.
How To Vacuum Seal Canning Jars
This technique uses a simple principle: removing air from a jar to slow down spoilage. It’s perfect for items that don’t require the heat processing of water bath or pressure canning. Think of it as an additonal layer of protection for your pantry staples.
Why Vacuum Seal Jars Instead of Using a Bag?
Jars offer some unique advantages over plastic bags. First, they are reusable and create less waste. Second, they are rigid, so you don’t have to worry about crushing delicate items like crackers or chips. Finally, glass is non-porous and won’t retain odors, making it ideal for strong-smelling foods like onions or garlic powder.
- Reusable & Eco-Friendly: Reduce plastic waste significantly.
- Protects Delicate Foods: No crushing of chips, crackers, or freeze-dried fruits.
- Odor-Proof: Glass won’t absorb or transfer smells.
- Stackable & Visible: Easy to organize and see contents at a glance.
- Multi-Purpose: Jars can go from freezer to fridge to pantry seamlessly.
Essential Equipment You’ll Need
You don’t need a lot of specialized gear. If you already do home canning, you likely have most of it.
1. Canning Jars & Lids
Always use genuine mason jars (Ball, Kerr, etc.) with two-piece lids. The flat lid has a sealing compound that creates the vacuum. Jars should be free of chips or cracks. Wide-mouth jars are often easier to fill and seal.
2. A Vacuum Sealer
You need a machine designed for sealing jars. There are two main types:
- Standalone Jar Sealers: These are devices made specifically for mason jar lids. You place a lid on the jar, set it on the machine, and it pulls the air out.
- Food Saver-type Machines with an Attachment: Many popular vacuum sealers come with a hose and a jar sealer lid attachment. You place the special attachment on your regular jar lid, connect the hose, and the machine does the work.
3. The Correct Lids & Attachments
For machines with a hose, you will use either reusable plastic jar sealer lids or the white plastic FoodSaver brand lids. You can also use a regular flat canning lid with a handheld vacuum pump that has a compatible attachment. Never try to suck air directly through a solid lid—you need the proper attachment with a valve.
Step-by-Step Guide to Vacuum Sealing Your Jars
Follow these steps for a successful seal everytime. It’s a straightforward process once you get the hang of it.
- Prepare Your Jars: Ensure jars are clean and completely dry. Any moisture on the rim can interfere with the seal.
- Fill the Jar: Add your dry goods. Leave about 1 to 1.5 inches of headspace at the top for the best results. For powdery items like flour, you might want to place a coffee filter on top to prevent the powder from being sucked into the machine.
- Wipe the Rim: Use a clean, dry cloth to wipe the jar’s rim. This is a critical step for a good seal.
- Apply the Lid: If using a dedicated jar sealer machine, place a new flat canning lid on the jar (ring optional). If using a hose-style machine, screw on your plastic jar sealer lid or attachment.
- Create the Vacuum: Place the jar on the machine or connect the hose. Activate the vacuum. You will hear the air being removed and see the lid get pulled down. The machine will usually stop automatically or beep when complete.
- Check the Seal: After vacuuming, you can apply a metal ring to the lid if you used a flat lid for storage, but it’s not always necessary for short-term. Test the seal by lifting the jar by the flat lid—it should hold firmly.
What Foods Are Best for Jar Vacuum Sealing?
This method is ideal for dry, low-moisture foods and some prepared items. It is not a substitute for pressure canning wet foods like vegetables or meat for shelf-stable storage.
- Dry Pantry Goods: Flour, sugar, rice, pasta, beans, coffee beans, tea, powdered milk.
- Snacks: Chips, crackers, nuts, trail mix, cereal.
- Dehydrated Foods: Home-dried fruits, vegetables, herbs, and jerky.
- Freezer Foods: Soups, stews, chopped vegetables, fruits, and meat. Important: For liquids in the freezer, leave ample headspace (2+ inches) as contents expand.
- Leftovers: Half-used bags of chips, partial boxes of crackers, or that leftover onion you need to store.
Common Mistakes to Avoid
Even simple processes can have pitfalls. Here’s what to watch out for to ensure your food stays fresh.
Using Damaged Jars or Lids
A tiny chip on the jar’s rim or a bent lid will prevent an airtight seal. Always inspect your equipment before use. The sealing compound on flat lids should be smooth and intact.
Sealing Moist or Oily Foods
Moisture and oils can compromise the seal and lead to rancidity or mold. Ensure foods like nuts or dried fruit are completely dry. For greasy items, consider a different storage method.
Overfilling the Jar
Not leaving enough headspace doesn’t allow the vacuum to form properly. Fine powders can also get sucked up. That coffee filter trick is really helpful for flour or powdered sugar.
Forgetting to Wipe the Rim
This is the number one reason for seal failures, just like in water bath canning. A single grain of salt or speck of flour can break the seal.
Creative Uses Beyond Dry Goods
Once you have the tool, you’ll find many clever applications for it around the kitchen and home.
- Marinating Meat Quickly: Place meat and marinade in a jar, vacuum seal it. The vacuum pulls the marinade deep into the meat in minutes instead of hours.
- Storing Craft Supplies: Keep buttons, beads, or sequins organized and dust-free.
- Protecting Important Documents: Place photos, papers, or matches in a jar and seal them to protect from moisture and air.
- Infusing Oils or Vinegars: The vacuum process can speed up infusion times for flavors like garlic or herbs.
- Preventing Freezer Burn: This is one of the best ways to store food in the freezer for long periods. Just remember that headspace rule for liquids.
FAQs About Vacuum Sealing Jars
Can you vacuum seal any glass jar?
No. You should only use jars specifically designed for home canning, like mason jars. They are tempered to withstand pressure changes. Regular pasta sauce or pickle jars may crack or shatter under vacuum pressure.
How long does food last vacuum sealed in a jar?
For dry goods in a cool, dark pantry, you can expect a significantly extended shelf life—often 2-5 times longer than in their original packaging. Frozen foods are protected from freezer burn for many months. Always label with the date.
Do you need to refrigerate vacuum sealed food?
It depends on the food. Dry pantry staples do not need refrigeration. Fresh, moist foods like chopped onions or meat absolutely must be refrigerated or frozen, as vacuum sealing does not kill bacteria.
Can you reuse the lids?
The plastic jar sealer lids are reusable many times. The standard metal flat lids with sealing compound are designed for one-time use to ensure a perfect seal, though some people reuse them for dry goods with mixed success. For best results, use new flat lids when possible.
Is it cheaper than using bags?
The initial investment in jars and attachments is higher, but because jars are reused indefinitely, it becomes much cheaper over time compared to constantly buying plastic roll bags or pre-made bags.
What’s the difference between this and canning?
Traditional canning uses heat to destroy microorganisms and create a shelf-stable seal for wet, high-moisture foods. Vacuum sealing jars simply removes air to slow oxidation and spoilage; it does not preserve food through heat sterilization.
Troubleshooting Seal Problems
If your seal isn’t holding, here are a few quick checks. First, listen to the machine. If it’s struggling to pull a vacuum, you likely have a leak. Check the jar rim for cracks or food debris. Ensure the lid or attachment is on straight and tight. If using a hose, check that it’s firmly connected to both the machine and the lid. Sometimes, a different jar or a brand new flat lid will solve the problem immediately.
Mastering how to vacuum seal canning jars is a simple skill with big rewards. It reduces food waste, saves money, and keeps your kitchen organized. With your jars, your sealer, and a few minutes of time, you can protect a huge variety of foods effectively. Start with a bag of rice or some nuts, and you’ll soon be looking for more things to seal away for later.