How To: Pressure Canning

Pressure canning preserves low-acid foods, eliminating bacterial contamination risk. It targets Clostridium botulinum, thriving in low-acid conditions.


Pressure canning is a method of preserving food in airtight containers at high temperatures using a specialized piece of equipment called a pressure canner. The primary purpose of pressure canning is to safely preserve low-acid foods, such as vegetables, meats, and poultry, by eliminating the risk of bacterial contamination, particularly the bacteria Clostridium botulinum, which can thrive in low-acid environments.

Do I really need a presure cooker for pressure canning?

Yes, you need a canner that can become pressurized. The canner uses steam and pressure to reach temperatures higher than boiling water alone, effectively destroying harmful microorganisms and their spores. It’s important to follow tested and approved recipes, processing times, and pressure levels for specific foods to ensure that the canning process is both effective and safe.

Why can’t I boiling water bath can low acid foods?

The high temperatures achieved during pressure canning are necessary to ensure the safety of low-acid foods because water bath canning, which relies on boiling water, may not reach temperatures sufficient to eliminate certain bacteria and spores. By using pressure canning, the internal temperature of the food can be raised above the boiling point, ensuring the destruction of potentially dangerous microorganisms and toxins.

What types of foods should you preserve with pressure canning?

Pressure canning is suitable for preserving low-acid foods that are more susceptible to bacterial contamination. These foods include:

  1. Vegetables:
    • Examples: Green beans, carrots, peas, corn, potatoes, and other root vegetables.
    • Note: Vegetables like tomatoes can be safely water-bathed due to their acidity.
  2. Meats:
    • Examples: Beef, poultry, pork, fish, and game meats.
    • Note: Ground meats are often recommended to be pre-cooked before canning.
  3. Poultry:
    • Examples: Chicken, turkey, duck.
    • Note: Remove excess fat before canning.
  4. Soups and Stews:
    • Examples: Vegetable soup, chili, beef stew.
    • Note: Ensure proper processing times for a mix of ingredients.
  5. Chili and Beans:
    • Examples: Chili con carne, baked beans.
    • Note: Beans should be soaked before canning.
  6. Stocks and Broths:
    • Examples: Chicken broth, beef broth.
    • Note: Strain stocks to remove solid particles.
  7. Prepared Meals:
    • Examples: Casseroles, pasta dishes, and other complete meals.
    • Note: Follow recipes designed for pressure canning.
  8. Sauces:
    • Examples: Spaghetti sauce, salsa, barbecue sauce.
    • Note: Ensure proper acidity or follow a pressure canning recipe.

What equipment do I need to pressure can foods?

  1. Pressure Canner:
    • Ensure it has a tight-fitting lid, a functioning pressure gauge, and a pressure relief valve.
    • Check the rubber gasket for any signs of wear and tear.
  2. Canning Jars:
    • Use standard Mason jars with new two-piece metal lids (flat lid and screw band).
    • Ensure jars are free of cracks or chips.
  3. Jar Lifter:
    • Essential for safely handling hot jars.
  4. Canning Funnel:
    • Helps in filling jars without spilling.
  5. Bubble Remover/Headspace Tool:
    • A plastic or wooden tool for removing air bubbles and measuring headspace.
    • Ensure it has a tight-fitting lid, a functioning pressure gauge, and a pressure relief valve.
    • Check the rubber gasket for any signs of wear and tear.
  6. Clean Cloths or Paper Towels:
    • For wiping jar rims and keeping everything clean.
  7. Sharp Knife:
    • For removing air bubbles, adjusting headspace, and ensuring there are no trapped air pockets.
  8. Recipe Ingredients:
    • Follow tested and approved recipes for the specific food you’re canning.

Step-by-Step Directions to Pressure Can:

  1. Prepare Jars:
    • Wash jars, lids, and bands in hot, soapy water. Rinse thoroughly.
    • Sterilize jars by boiling them for 10 minutes or use the sterilize function on a dishwasher.
    • Keep jars hot until ready to use, either by placing them in a low oven (about 200°F or 93°C) or keeping them in hot water.
  2. Prepare Ingredients:
    • Wash, peel, chop, or prepare the food according to the recipe.
    • Cook the food as directed in the recipe.
  3. Fill Jars:
    • Place the canning funnel over the jar.
    • Use a ladle to carefully fill the hot jars with the prepared food, leaving the recommended headspace (usually 1/2 to 1 inch).
  4. Remove Air Bubbles:
    • Run a non-metallic spatula or bubble remover tool around the inside of the jar to release trapped air bubbles.
    • Add more food if needed to maintain the proper headspace.
  5. Wipe Jar Rims:
    • Moisten a clean cloth or paper towel with hot water.
    • Wipe the rims of the jars to remove any residue or food particles.
  6. Apply Lids and Bands:
    • Place a sterilized lid on each jar, ensuring the sealing compound is in contact with the jar rim.
    • Screw on the metal band until it’s fingertip-tight (not too tight).
  7. Prepare Canner:
    • Add the recommended amount of water to the pressure canner according to the manufacturer’s instructions.
    • Place the canning rack in the canner.
    • Load the filled jars onto the rack, ensuring there is space between each jar.
  8. Secure Lid and Vent:
    • Align the canner lid properly and lock it in place.
    • Follow your canner’s instructions for venting (usually involves allowing steam to escape for a specified time).
  9. Build Pressure:
    • Close the vent and bring the canner to the specified pressure according to your recipe.
    • Maintain the correct pressure throughout the processing time.
  10. Process Jars:
    • Process jars at the recommended pressure and time for your specific food.
    • Adjust heat as needed to maintain pressure.
  11. Cool and Check Seals:
    • Once processing is complete, turn off the heat and let the canner cool naturally.
    • Wait for the pressure indicator to drop to zero before opening the canner.
    • Carefully remove jars with a jar lifter and place them on a towel or cooling rack.
    • Allow the jars to cool completely, usually for 12 to 24 hours.
    • Check seals by pressing down on the center of each lid; it should not flex or pop. If a lid doesn’t seal, refrigerate that jar and use it promptly.
  12. Store Jars:
    • Label sealed jars with contents and date.
    • Store jars in a cool, dark, and dry place.

NOTE: My canner only holds 10 pints or 6 quarts. I try to do things in batches like that but sometimes I prepared too many at one time. They need to stay warm while I wait to do the next batch. If they don’t the jars will break. I put a couple inches of water in a pan, turn the heat to medium and keep the contents warm until they can go in the canner.

Remember to consult reliable canning resources or the USDA guidelines for processing times and pressures, as they can vary based on the type of food being canned. Always prioritize safety and follow tested recipes.

Leave a Reply

Your email address will not be published. Required fields are marked *