Canning can be a good way of preserving foods. When you can food at home, the process of heating it in jars at a high temperature for a certain length of time kills organisms, like molds, bacteria, and yeast. This is what preserves the food. Later, the tight sealing of the containers keeps these organisms out. A boiling water canner is usually used to can various foods, such as tomatoes.
However, remember that canning tomatoes at home requires patience, time, and a fair amount of skill. Usually, it is the first attempt at canning that can be the hardest. Later, once you get familiar with the process, it gets much easier, and can even be fun.
By planning the process and doing it in steps, as given below, canning tomatoes can become an easy job:
- Collect the equipment
- Choose and then thoroughly wash the tomatoes
- While you sterilize the jars, prepare the tomatoes
- Pack them into the jars, adding acid if required
- Put on the lids as well as the screw bands on the jars
- Process the jars in boiling water for the required amount of time
The Canner: Either buy or borrow a canner which has a lid. If you buy it, check to see whether it is tall enough for a rack to be fitted at the bottom, and accommodate quart jars kept upright, with about two inches left above the jars for the boiling water to roll freely.
You can even use a large sized stockpot if the above requirements are met. However, you will have to make a rack, to be fitted at the bottom, in order to support the jars as well as allow the boiling water to circulate. Some electric ranges will require you to use a flat-bottomed canner.
The Jars: It is best to use regular mason jars. These are less likely to break because the glass they are made of are of heavier weight compared to pickle jars. Do not use cracked or chipped jars. Wash the jars in hot, soapy water, then rinse and dry them out.
The Lids: The lids that are in use these days are flat metallic ones, which are kept in place while the canning process is in progress by a metallic screw band. The bottom edge of the lids are crimped in order to form a furrow that is filled with a compound, which becomes soft and flows a little during the canning. This is so that it seals the surface and yet lets the air escape from the jar when it is heated. After the canning process is done, and the jars cool down, this gasket forms an airtight seal. While the metallic band of rings can be reused, the flat lids have to be bought anew.
Other Equipment and Supplies
- A sturdy jar lifter
- A funnel to fill the jars
- A wire basket
- A spatula
- 2 large saucepans or bowls
- A chopping board
- A sharp knife
- A long handled spoon
- A large enamel or stainless steel saucepan
- Salt and lemon juice
- A kettle
- Raw Pack or Hot Pack (according to your choice)
- Raw pack, also known as a cold pack, involves packing the raw, skinned tomatoes into the jars and covering them with boiling water or hot tomato juice. While this may be quicker, the results; however, may be disappointing. Raw tomatoes have a lot of air in them. Hence, during the canning process, they tend to shrink and float up. Although it is safe, but it certainly does not appear appealing.
- Hot pack, on the other hand, involves filling the jars with tomatoes that have been skinned and cut into pieces, and then heated until they boil in their own juice. This allows more tomatoes to be filled in the jars.
♨ The tomatoes should not be picked more than six to twelve hours before they are canned. Don't use the ones that are bruised, cracked, or have blemishes on them. Make sure to wash them thoroughly.
♨ Fill half the canner with water and put it on the heat. Fill the jars partially with water and place them on the rack in the canner for sterilization. Boil the jars for about ten minutes.
♨ While the jars are being sterilized, skin the tomatoes. You can do this by putting them in the wire basket and dipping it into a bowl of boiling water for about 30 to 60 seconds, then removing it and immediately dipping it in a bowl of cold water. The skin comes off quite easily then.
♨ Then, cut the skinned tomatoes into quarters and heat them in a large sized kettle so that the tomatoes give off their juice.
♨ Use the jar lifter to remove the sterilized jars from the canner, and place them on a soft towel or folded newspaper in order to prevent them from cracking.
♨ Put two tablespoons of lemon juice in each jar. If you want, you can also add one teaspoon of salt for flavor.
♨ Use the funnel and fill each jar with the hot tomatoes, being careful to leave about one inch space at the top.
♨ Slide the spatula between the tomatoes and the glass of the jar in order to remove air bubbles.
♨ Wipe the top edge of each jar carefully. Then put the lids in hot water to soften the sealing compound, which takes about five minutes. Next, place the lids carefully on the rim of each jar.
♨ Fix the screw bands over each lid, and tighten them. However, take care not to tighten them excessively, because this will prevent the air from escaping from the jars, and thus result in the jars not getting sealed properly.
♨ Load the filled jars into the canner and heat the water again. The level of the water should be about one inch over the top of the jars. Let the water come to a boil and process the jars for about 45 minutes if you use quart jars, and 35 minutes if you use pint jars.
♨ Again, use the lifter to remove the jars, and place them on newspaper layers or a wooden board, ensuring that there is enough space between each jar. Then, let the jars cool completely.
♨ While the jars cool, the contents inside contract, pulling the lid down and creating a vacuum. As the lids curve downward, you will hear snapping sounds, which is a sign that they have been sealed well.
♨ Let 24 hours elapse, then label the jars and store in a cool place. If you find that a jar hasn't been sealed properly, you can use a new lid and process it again.
♨ Store these cans in a cool and dry place and, use them within a timespan of a year. If you see the tomatoes floating above, and the water at the bottom of the jar, don't get worried. This separation does happen, and it is quite normal.