Since the early 1800’a people have been using canning as a method to preserve food. Canning allowed the early pioneers and settlers to preserve their harvest and store it for winter months.
Canning Foods – Water Bath and Pressure Canning
Now that we know a little of the history of canning from our Preserving Food lesson, we can learn about how to actually can! Canning can be intimidating, but once you have done it, you will find it’s not that difficult.
*Please note that this lesson is a general overview. Please read the instructions for your canning materials and follow them. Canning is a wonderful pursuit, but there are some dangers and Pioneer Learning is not responsible for injuries that may occur. *
- Always check for the most current instructions on safe canning – don’t rely on your grandmother’s method!
- There are many resources available at the website for the National Center for Home Food Preservation.
- The Ball Blue Book Guide to Preserving is also a good resource, as long as you use the most current version.
- The mason jar was patented in 1858, and that began the home-canning industry.
- It was simply called open-kettle.
- Jars that were hot were filled all the way to the top with hot, cooked food.
- Then the lids were put on, and it was supposed to create a vacuum that formed an airtight seal as things cooled.
- Usually this was used for fruits and because they were high-acid, it was considered safe until World War II.
- Today, open-kettle is not considered a safe canning method.
- Another method that was used in the past is oven-canning.
- This method tried to preserve food by baking it.
- The dry heat of an oven does not suffice to preserve the food safely.
- No, you cannot safely can in a dishwasher, crock-pot, or compost heap.
Thing to consider when canning
Canning is a wonderful science lesson. There are so many things to consider when you are canning.
- If you are canning high or low acid foods.
- Know the elevation where you are canning.
- Understand the kind of heat you are using for it. Electric, gas, wood?
- The processing times and amount of pressure required to can at.
It sounds very complicated, but you will find it really is not.
What do you need to be able to can?
- Large, deep canner or big stockpot with a lid for water-bath canning
- Rack for the water-bath canner
- Pressure canner for pressure canning
- Pot for blanching or pre-cooking
- Jars not chipped or broken with lids that will seal
- Funnel – wide mouth to make filling jars easier and less messy
- Jar lifter for taking the jars out of the canner
What items can you process in a water-bath canner?
Water-bath canning is suited to high acid foods and fruits.
Some of the items you might process are
- Fruit juices
- Salsa (depending on the recipe you use this can be pressure canned or water bath)
- Pie Fillings
Does your family eat any of these items? Do you already can some of them?
Water Bath Canning
Water-bath canning is not too difficult.
- The first thing you need to do is make sure your kettle is big enough.
- There is a rack inside to set the jars on.
- This needs to have ½-1 inch space between it and the bottom of the kettle.
- You need to be able to fill the kettle with water to cover the jars 1-2 inches with water
- Room for 1-2 inches of extra space for boiling water.
Water Bath Canning Instructions
- Place the kettle on the stove with the rack in it and fill half-way with water.
- Be sure you have a kettle or teapot warming with extra water.
- Turn on the heat to the kettle.
- Get the food ready according to the instructions for that food.
- The jars should be clean and scalded, then fill them, leaving the proper head space.
- Headspace is the amount of room between the food and the top of the jar – usually ¼ to 1 inch
- Screw the lids on finger tight.
- Only do one type of food at a time, in one size of container.
- Put the jars on the rack, keeping them away from the sides of the pot and spacing them about an inch apart.
- If you don’t have enough jars to fill the canner, put in jars full of water in the canner to prevent rattling.
- Pour hot water around (not on top) the jars until the level is 2 inches above the tops of the jars.
- Turn up the heat to reach a full rolling boil and then put the lid on the kettle.
- Start timing according to the recipe you are following.
- Keep the water gently boiling for the whole time.
- When the time for processing is done, turn off the heat and let sit for 5 minutes.
- Remove the jars using your jar lifter
- Be careful not tip the jars because it could interfere with the seal.
- Set the jars on a towel on the counter about an inch apart.
- Let them rest, undisturbed, between 12-14 hours.
- You will hear pinging sounds as the lids are flexing and sealing. This sound is music to a canners ears!
- Once they have cooled properly, press the lid.
- If it is solid and doesn’t wiggle, remove the ring and carefully lift the jar from the edge of the rim.
- You should be able to lift it that way.
- If the seal is not complete, refrigerate the jar and consume it quickly.
- If 24 hours has not passed, you can reprocess the jar with a new lid.
Pressure Canning seems to be the most intimidating method of canning for many people, but it doesn’t need to be.
What is a pressure canner?
It is a kettle that is covered with a tight-fitting lid that has a pressure gauge and release valve, aka the controls. The lid is held on with clamps or ridges and grooves that interlock. There may be a rubber gasket, but not necessarily on all models.
The controls are a pressure gauge of some sort, an open vent to let air and steam vent, and a safety valve that blows if the pressure gets unsafe. There is also a rack to keep jars from touching the bottom of the canner.
Foods you can Pressure Can
What foods do we pressure can?
- Salsas (depending on the recipe you use this can be pressure canned or water bath)
Pressure Canning Instructions
*Make sure to read the instructions on your pressure canner for specifics, every canner is different.
- Add 1 ½ inches of warm water in the canner
- Place over high enough heat to raise pressure quickly after the lid is clamped on.
- Be sure your jars are clean and scalded
- Fill the jars, leaving the proper headspace
- Headspace is the amount of room between the food and the top of the jar – usually ¼ to 1 inch.
- Once the jars are in the canner, put the lid on and tighten.
- Next you need to let it vent, leaving the vent open until steam is strong and steady from it – this could take 7-10 minutes.
- Once your pressure canner has vented, close the vent following the directions for the type you have – either dial or weighted gauge.
- If you have a dial, let the pressure rise until it reaches about ½ pound under the pressure you need.
- Then reduce the heat a little to slow down the building pressure.
- Once you reach the pressure needed, adjust the heat to keep it at that level.
- If you have a weighted gauge, follow the same instructions, but keep track of the jiggles as directed by the manufacturer.
- The pressure needs to be consistent.
- If it drops, you need to get it back to the needed level and start timing again.
- This will cause your food to be overcooked, so be sure you keep your eyes on the pressure.
- When the time is up, turn off the heat and let cool until the pressure reaches zero.
- Once it does, open the vent slowly. Once steam stops coming out of the vent, you can open the lid.
- Open it away from you so the heat and steam that remain will not hit you.
- Remove the jars and place on a protected surface to cool.
- Test the seals after they have cooled.
Note that pressure canning can be dependent on the altitude you live at, so be sure to read all instructions!
Printable Pressure Canning Instructions
Life Skills/Language Arts/Handwriting/Science/Art/Math
This age group can help put vegetables in jars for preserving. They can start to learn to write and spell the names of the vegetables they are helping preserve. Let them take a small taste if you use a brine and explain simply how the brine will keep the vegetables from going bad. They can help gather supplies. Have them draw pictures of canned goods on shelves or of the jars full of vegetables. Use the printable activity page and have them draw or cut out pictures to fill the canning jar printable. They could even make their own shelf of ‘canned goods’ with the pictures!
This age group can be much more involved.
- Start teaching them how to preserve the food from start to finish.
- Teach them food safety when canning.
- Let them help make a list of the foods you are preserving.
- If you do not have a canning inventory, have them create one and fill it out.
- If you are not canning this season, have them make one that would show a pantry that you could feed the family from all winter.
- They can figure how much food each family member would eat and decide how many jars would be needed of each item.
This age group can also help can food from start to finish.
- Let them help with your fall food preservation.
- Have them research the science behind food preservation.
- This could be a good starting point: How Food Preservation Works
- Present an oral or written report on canning safety.
- Figure out your elevation and any special canning techniques that might be specific to your area.
- Calculate how much food needs to be canned for the family to eat all winter.
Printable Canning Inventory Sheet<<<<
Canning Food Math
- How many jars do you need?
- How much food do you have in each jar? Weight vs volume?
- What is your altitude?
- According to your altitude, how much time do you have to adjust for your canning recipe?
- Use an analog clock to time the canning process
Weekly Bible Verse
Psalm 16:1 Preserve me, O God: for in Thee do I put my trust.
When we trust the Lord, He preserves us. He keeps us in His tender care and shows us the way we should go. If we trust the Lord with our homestead and homeschool, He will guide us and show us the things we need to do and learn. If we ask Him to bless our lives, He will do so.