When canning onions, it is best to use a pressure canner. Onions should be washed and peeled, then blanched and hot-packed into clean canning jars, leaving a one-inch headspace. Process at a PSI according to your altitude for 40 minutes, and allow to cool overnight before storing.
What is the Best Way of Canning Onions?
Onions have a low acid content, so pressure canning is the best method to avoid botulism.
How to Prepare Onions for Canning
Whether it’s store-bought or fresh-picked onions, here’s how to get onions ready for the canning process:
- Sort your onions. Remove any scarred, soft or immature onions.
- Wash onions thoroughly in cool water.
- Peel onions by removing the outer layers and rinse again after removing the skin.
- If the onions are large, cut them into halves or quarters.
- Place your prepared onions in boiling water and blanch for 3-5 minutes. Quickly rinse them in cold water to stop them from cooking.
- Transfer the onions to clean, sanitized hot jars and leave at least an inch of headspace.
- Add ½ teaspoon of salt for pint jars and one teaspoon for quart jars.
- Fill the jars with boiling water maintaining 1-inch headspace.
- Remove excess air bubbles using a spatula by running it along the inside of each jar.
- Wipe the rims of the jars, cover them with a lid, and tighten the screw bands to fingertip tight.
Pressure Canning Onions Guide
Once the onions are clean and packaged, it’s time for pressure canning.
- Fill your pressure canner with 4 inches of hot water and place it on the stove over low heat with the lid off.
- Using jar tongs, place the sealed jars containing your onions on the jar rack. Follow the manufacturer’s instructions on the proper water level before closing the canner.
- With the weight off or the valve open, turn it to high heat and allow the canner to vent steam for approximately ten minutes.
- Put the weight on or close the valve and let the pressure build to the necessary pounds of pressure based on your altitude. Process the jars per the tables below:
Processing time and pressure for onions in a dial-gauge pressure canner.
Altitude | 0 – 2,000ft | 2,001 – 4,000ft | 4,001 – 6,000ft | 6,000 – 8,000ft |
Pints: 40 minutes | 11lbs | 12lbs | 13lbs | 14lbs |
Quarts: 40 minutes | 11lbs | 12lbs | 13lbs | 14lbs |
Processing time and pressure for onions in a weighted-gauge pressure canner.
Altitude | 0 – 1,000ft | 1,001ft + |
Hot Pack (Pints) 40 minutes | 10lbs | 15lbs |
Hot Pack (Quarts) 40 minutes | 10lbs | 15lbs |
- After the processing time has passed, turn off the heat and allow the canner to cool. Wait until you hear a clicking sound before opening your canner.
- Open the canner and remove the jars using a jar lifter. Carefully place them in a safe area to cool overnight. The jars may make a popping sound as they seal.
- Once the jars are completely cool, remove the screw bands and check that the seals are tight.
- If the seal is indented, it is ready for labeling and storage.
- If a jar doesn’t seal, you can reprocess it with a new lid or put the jar into the refrigerator and consume the onions within two days.
Water Bath Canning Onions
Water bath canning onions is not recommended because onions are a low-acid vegetable.
If you plan to process onions in a water bath canner, it is vital to raise the acid level (pH) of the onions before processing them by pickling them first and using canning or pickling salt.
How Long Does it Take to Can Onions?
The process of pressure canning onions takes a total time of 45-60 minutes, excluding the prep time. Water bath canning pickled onions will take 30-50 minutes.
What Can You Do With Canned Onion?
Did you know you can substitute canned onions for fresh ones in most onions recipes? Try canned onions in these delicious dishes:
Caramelized Secret Chocolate Cake
What’s the secret savory note in this decadent chocolate cake? You guessed it! Caramelized onions are the star of this sweet treat.
Onion Sauce
This naturally sweet, healthy sauce will dress your meats and pasta while adding layers of flavor!
Vegetarian Pizza
Forget unhealthy toppings and try this nutritious pizza topped with onions!
Can Caramelized Onions be Canned?
Caramelized onions are mildly acidic and can be pressure canned safely.
It’s best to follow home canning procedures for fresh bulbs. Adjust the timer on your pressure canner accordingly, as caramelized onions require a processing time of 70 to 75 minutes.
Best Onions for Canning
Smaller onions are easier to pack in jars and are naturally sweet, but most onion varieties are well-suited to canning, including:
- Cipollini
- Pearl cocktail onions
- Red onions
- Scallions
- Shallots
- Sweet Spanish
- Vidalia
- White onion
- Yellow onions
How Long Can Canned Onions be Stored?
If stored under proper conditions, sealed, pressure-canned onions can last for 3-5 years. However, most experts agree that it’s best to consume canned veggies within two years so they retain their original flavor and nutritional value.
Be sure to store your onions away from moisture, heat, and sunlight to prevent spoiling and maximize shelf life.