Canning that uses boiling water for preserving tomatoes is necessary, and one way to do so is by canning tomato paste. The tomato paste recipe created at home is similar to tomato sauce, but because it is reduced during cooking, it is far more concentrated. This not only means that it takes up less room in the pantry, but it also means that it imparts more flavor onto each teaspoonful of food that is prepared at home. We actually raise hundreds of pounds of tomatoes every year, and while we eat plenty of them fresh when they are in season, we are always seeking active ways to preserve tomatoes so that we can use them throughout the colder months. I will entire tomatoes because it is simple and quick to do so, despite the fact that doing so will require a lot of room on the shelf in the pantry. Even while you can use a food mill to peel and seed the tomatoes before canning tomato sauce, which makes the process of canning tomato sauce even simpler, you are still keeping a significant amount of water in each jar. On the other hand, tomato paste is made by cooking tomatoes down until they concentrate their flavor and nutrients. Just one tablespoon is all you need to infuse virtually everything with a deep and complex taste. Because the majority of the liquid has already been removed, this means that you are only adding flavor (instead of additional water that you will need to boil off later). Making tomato paste requires a little more patience and some more preparation work, but it ultimately results in faster dinners later on. 
tomato paste recipe
According to the recipe to make tomato paste, you’ll need 14 pounds of Roma- or paste-type tomatoes as well as one teaspoon of citric acid, two bay leaves, one teaspoon of canning or pickling salt, and one whole clove of garlic (the garlic and bay leaves are optional, but give the finished tomato paste some added zest and depth of flavor). This quantity will produce around 8 to 9 half-pint jars, which is the size that works best when canning tomato paste at home and will be the yield from this quantity. During the stage of processing in which the thick paste is being handled, the likelihood of the heat not penetrating the paste increases if you use a larger jar. The procedure of manufacturing tomato paste is identical to that of making tomato sauce; the only difference is that the sauce is reduced and boiled for a longer period of time in order to achieve a considerably higher concentration of solids. Cooking tomatoes until they have lost at least one-third, one-half, or three-quarters of their initial volume results in the production of a thin sauce, a thick sauce, and tomato paste, respectively. 
The sauce is only cooked until it becomes thick enough to stand up on a spoon, at which point it is no longer considered a sauce but rather a tomato paste. To prepare the tomatoes, give them a thorough washing, pull off the stems as you work, and remove any sections that are damaged or discolored from the tomato. If you have access to a large sieve, chinois, or food mill, you don't need to worry about removing the skin or seeds at this point in the process. If you do not have any of these pieces of equipment, you can manually peel and seed the tomatoes prior to cooking them in the sauce. This step comes before cooking the tomatoes. In the piece that I wrote about preserving diced or crushed tomatoes, I provided comprehensive instructions on how to carry out these steps in the most effective manner possible. When a tomato is split open, its liquids tend to separate rapidly; but, if you use a method that involves high heat and consistent crushing or mashing, you can prevent the tomato juices from separating. This following step is not absolutely necessary because separated tomato liquids are totally OK to consume (and are harder to avoid if you are peeling and seeding the tomatoes by hand), but it does yield a smoother and more cohesive outcome whether you are producing canned tomato paste, sauce, or juice. 
tomato paste recipe for canning
When it comes to creating tomato paste, Roma-style tomatoes, which have low moisture and low seed, are the best-suited tomatoes for canning in practically every manner. This is because Roma tomatoes have a lower seed count and lower moisture content. The flesh of Roma tomatoes is particularly meaty and dense, and it may more easily be reduced to a smooth paste than the flesh of any other variety of tomato. The Roma tomatoes that are offered in supermarkets are virtually invariably of the Heinz kind. This flavorless tomato was produced by the Heinz Corporation which is also the name of the firm that makes ketchup. Having said that, by all means, use Heinz tomatoes if that is all you have access to given the circumstances. Because of the prolonged exposure to heat during the cooking and canning process, you will still end up with a tasty tomato paste when you are finished. This is because the heat will bring out any of the fruit's more subtle sweet flavors. If you have the space to grow your own tomatoes, I would recommend planting a few heirloom kinds (there are lots to pick from, more than you might think there are!). If you have the space to grow your own tomatoes, I would suggest planting a couple of heirloom varieties. After they have been collected, you will have a lot of fun experimenting with all of the different tastes and textures that they offer. You may cultivate a wide variety of Roma tomatoes, but the Amish Paste, Hogs Heart, and Opalka cultivars are among my all-time favorites for growing Roma tomatoes. 
When working with around one pound of prepared tomatoes at a time, cut the fruit into quarters after washing it and removing the stem. When the tomatoes have been cut into quarters, add them to the saucepan and mash them using a potato masher or a large spoon while the heat is high. Do this until the tomatoes begin to boil Resist the temptation to cut up all of the tomatoes in advance because the juices will start to separate almost immediately after you do so. Repeat this procedure as many times as necessary, boiling and mashing the tomatoes in between each iteration, until all of the tomatoes have been included. Regular stirring is necessary to prevent the tomatoes and the bottom of the skillet from becoming scorched. When you have finished adding all of the tomatoes, turn the heat down to a low setting and continue to simmer the tomatoes, uncovered, for one hour, or until the volume has decreased by half. My preferred method is to use the food mill attachment of my Kitchen Aid stand mixer, which is both fast and convenient. Cooked tomatoes should be processed through a sieve or food mill to get rid of the skins and seeds. If you want a smooth paste, you might be tempted to use a blender or food processor, but you should avoid doing that. In addition to creating a silky texture, the blades of these machines will whip undesired air into the tomato paste, which will prevent the paste from being sealed properly when canned.