Canning is a type of food preservation that uses a hot water bath to seal food inside sterilized jars. In cold pack canning, you can prepare raw or uncooked food and sauces, such as tomato sauce, for processing in jars in a large pot or canner filled with boiling water. With a tomato sauce recipe to suit your tastes and the correct canning method, cold pack canning will help you preserve tomato sauce for up to three years.
Things You'll Need
Jars with lids
Make a tomato sauce according to your individual taste. For cold pack canning, make the tomato sauce without cooking it. You may want to blend fresh tomatoes with various spices, seasoning or oils, according to your taste. Only include foods that are safe to consume raw in your sauce for cold pack canning; therefore do not include items, such as meat or poultry.
Boil your jars in a large pot for 10 minutes to sterilize them; however do not boil the lids. Leave the jars in the hot water.
Remove one jar at a time from the hot water. Add 1 tsp. of lemon juice before you add the tomatoes. Tomatoes are low-acid fruits and, for proper preservation, food needs to be above a pH level of 4.6. Adding lemon juice will help raise the pH to a safe level for canning. After you have added the lemon juice, fill the jar up with the tomato sauce, leaving 1/2-inch of space from the top. Try not to spill the sauce and use a funnel if it will help you get the sauce into the jar without spilling. Once the jar is filled, stir the contents of the jar with a rubber spoon to get rid of air bubbles.
Tighten the jar lids after each jar is filled.
Fill a large pot with enough water to submerge all your jars. You should be able to fit between seven and nine jars in a large pot. The jars should be fully submerged in the water with an additional 2 inches of water over the top of the lids. To be extra safe and prevent the jars from breaking, you can place a wire rack on the bottom of the pot before you fill it with the water and the jars.
Bring the water to a boil and boil the jars for 45 to 50 minutes. If you are following a cold pack canning recipe for your tomato sauce, follow the time required by the recipe.
Take the jars out of the water one at a time with tongs. Set them on a cotton towel to cool. As they cool, you should hear them begin to pop their lid locks, which means they are properly sealing. If after several hours they have not popped their locks, press down on the lid with your finger to try to lock the jar. If the jar does not lock, it is not properly sealed and you should discard the sauce in that jar.
Store the sauce in a pantry or closet that is cool and dry and protected from sunlight. You can keep the tomato sauce for up to three years.
- Canning USA Supply Store; Raw Pack, Cold Pack and Hot Pack Canning; David G. Blackburn; 2011
- North Dakota State University Extension; Why Add Lemon Juice to Why Add Lemon Juice to Tomatoes and Salsa Before Canning? Tomatoes and Salsa Before Canning?; Julie Garden-Robinson, et. al.; January, 2009
- Canning Basics: Canning Food