Introduction to Canning Food

Canning will preserve food by killing pathogens, stopping activity of enzymes and removing oxygen to create a tight vacuum seal that prevents contaminants from re-entering food.

Hot Water Bath Canning or Pressure Canning

There are two safe methods for canning food: Hot Water Bath canning and Pressure canning. It is important to use the right method of canning for your food.

Which Method to Use?

The acid level in the food you want to preserve will determine which method to use.

HOME CANNING METHODS

HOT WATER BATH CANNINGPRESSURE CANNING
High Acid Foods (pH less than 4.6)Low Acid Foods (pH more than 4.6)
FruitVegetables
Fruit juiceMeat
Tomatoes with Acid addedPoultry
Salsa RecipesFish and shellfish
Pickled vegetablesSoups
Pickled condiments (relish)Stews
Jams & JelliesAny high/low acid combination sauce

It is not safe to can low acid foods using a hot water bath. If you can high acid foods in a pressure canner you will get poor texture, colour and quality. Using the right method for canning will ensure safe, good quality food preservation.

Low acid foods (pH higher than 4.6), including most vegetables and meats, cannot be processed by hot water bath canning because some bacteria, like botulism, and their spores can live in low acid foods. Low acid foods must be canned by pressure canning to reach a temperature that kills bacteria.

For foods that are a combination of low and high acid, like tomato sauce with added meat and vegetables, food is considered low acid and needs to be pressure canned.

Hot Water Bath Canning

This method of canning is when jars are filled with food, sealed loosely with a lid, completely covered in boiling water and boiled for a set amount of time.

This method is for high acid foods like fruit, fruit juice, jams, jellies, tomatoes with added acid (like lemon juice or vinegar) and pickled vegetables only (pH less than 4.6).

For a detailed video with description of the supplies needed for Hot Water Bath Canning, watch this video from the Manitoba Agriculture Northern Gardening resources: Canning Supplies for Water Bath Canning.

There is also an instructional video on How to Make Jam.

For easy-to-follow instructions, check out How to Hot Water Bath by Manitoba home economist, Getty Stewart.

Pressure Canning

This method uses a special canner that seals tightly and processes food under high pressure. The pressure in the canner raises the temperature above boiling which is high enough to kill bacteria and their spores. Pressure canning is used for low acid foods like vegetables, meat, fish, poultry and mixed foods like soups and sauces.

In this method, jars are filled with food, sealed loosely with a lid and put in a pressure canner (not a pressure cooker) with only a liter (quart) or two of water. The canner is sealed with a tight-fitting lid, brought up to the correct pressure by heating on the stovetop element, and jars are processed for a set time. After the time is up, the element is turned off and the canner cools gradually releasing its pressure before the lid is removed and jars are taken out. How much water to add to the canner, what pressure to use and for how long to process jars, varies depending on the food in the jars and is included in tested, trusted recipes.

For detailed videos with description of the supplies needed for pressure canning, as well as the complete process of canning fish, watch these videos from the Manitoba Agriculture Northern Gardening resources:
Supplies for Pressure Canning.
Pressure Canning Fish

For more information on pressure canning, check out How to Pressure Can from the National Center for Home Food Preservation.

Can I use my Instant Pot or Pressure Cooker to Pressure Can Food?

Electric pressure cookers like the Instant Pot are different than pressure canners. Pressure cookers work differently than canners and do not reach the necessary temperatures needed for safe canning. There is not enough research to know the exact time and process to use with pressure cookers; they are not recommended for pressure canning.

You can use your pressure cooker for hot water bath canning high acid foods by using it like a big pot and not using any pressure.

Where can I find safe recipes?

There is often new information and research providing further recommendations for safe canning practices. What was done 25 years ago, is often not the best method today. It is likely that your grandmother’s recipe or instructions for canning do not follow current safety guidelines and practices.

To be sure you are getting current, safe and nutritious information, follow recipes and instructions from trusted, credible sources. The leading source of credible information and the organization regularly doing testing on safe canning practices is the US National Centre for Home Food Preservation.

The Government of Canada also has food safety tips for home canning in the article Home Canning Safety.

Get recipes and tips from these credible sites or professionals.
Bernadin
Healthy Canning
Kraft Canada Certo Brand
Getty Stewart, PHEc
National Center for Home Food Preservation – Meats, Poultry and Fish
National Center for Home Food Preservation – Vegetables and Soup

Interested in reading more? Check out these blog posts from the H&F Hub:
Making Jams and Jellies
What to Do When your Jelly Doesn’t Set
How to Use Chokecherries
You Can – Can Tomatoes