Canning tomato paste is one method of preserving tomatoes, how it is prepared easier by using a canner that uses boiling water. Another method is to can whole tomatoes. Homemade tomato paste is comparable to store-bought tomato sauce; but, due to the fact that it is reduced during the cooking process, it is far more concentrated. This not only means that it takes up less space in the pantry, but it also means that it transmits more flavor into each teaspoonful of food that is produced at home. This is because it is a more concentrated form of seasoning. Although we eat a sufficient number of fresh tomatoes while they are in season, we are always seeking efficient ways to preserve tomatoes so that we may use them during the colder months of the year. Every year, we grow many hundreds of pounds of tomatoes. In spite of the fact that there won't be much room left on the shelf in the pantry after I'm done, I will proceed with canning whole tomatoes because it is a straightforward and speedy process. Even if you 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 retaining a significant amount of water in each jar after canning tomato sauce. 
This is because the food mill does not remove the seeds from the tomatoes. On the other hand, tomato paste is produced by simmering tomatoes until their flavor and nutrients are concentrated. This process takes a long time. It only takes one tablespoon to impart an intricate flavor profile on almost any food or beverage. Due to the fact that the vast bulk of the liquid has already been extracted, this indicates that all you are doing is adding flavor (instead of additional water that you will need to boil off later). Producing tomato paste involves a little more patience and a little bit more preparation work, but in the end, it results in dinners that are ready to eat much more quickly. When it comes to making tomato paste, Roma-style tomatoes, which are low in moisture and low in seed, are the best-suited tomatoes for the job in virtually every way. These tomatoes have a thicker skin and fewer seeds than other varieties of tomatoes. This is due to the fact that Roma tomatoes contain a lower amount of moisture and seeds compared to other types of tomatoes. It is possible to more readily reduce the flesh of Roma tomatoes to a smooth paste than it is possible to reduce the flesh of any other species of tomato. Roma tomato flesh is particularly meaty and substantial. 
The Roma tomatoes found in grocery stores are virtually usually of the Heinz kind, which is a flavorless tomato developed by the Heinz corporation, which is also the name of the firm that produces 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 couple of heirloom varieties (there are plenty to choose 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. 
To make tomato paste, you will need 14 pounds of Roma or paste-type tomatoes, one teaspoon of citric acid, two bay leaves, one teaspoon of canning or pickling salt, and an entire clove of garlic. Additionally, you will need to use one teaspoon of citric acid, one teaspoon of canning or pickling salt, and one teaspoon of pickling salt (the garlic and bay leaves are optional, but give the finished tomato paste some added zest and depth of flavor). The yield from this number will be approximately eight to nine half-pint jars. This is the jar size that works best for home canning of tomato paste, and it will be the size that is produced by this quantity. If you use a larger jar during the stage of processing in which the thick paste is being handled, there is a greater chance that the heat will not penetrate the paste. This risk grows as the size of the jar increases. It is time to use either a food mill or a large sieve/chinois after the volume of the tomato combination that has been crushed has fallen to one-half of its initial size (if you cored, peeled, and seeded the tomatoes by hand you can skip this next step, continuing to cook for the time outlined below). 
I like to use the food mill attachment that comes with my KitchenAid stand mixer since it makes the procedure more efficient and less complicated. To remove the peels and seeds from the cooked tomatoes, you will need to pass them through either a sieve or a food mill after they have been cooked. This step can be done with either piece of equipment. Resist the impulse to use a blender or food processor to make a smooth paste because doing so could be more convenient, but you should instead try to make the paste by hand. The blades on this kitchen equipment produce a silky texture, but they also whip unnecessary air into the tomato paste. This is not something you want to happen if you intend to can the tomato paste in the near future. 
tomato paste recipe for canning
The procedure of manufacturing tomato paste is from an identical recipe for canning tomato paste. The only difference is that the sauce is reduced and simmered 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. 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 process of boiling and mashing the tomatoes until all of the tomatoes have been incorporated into the dish. Continue until all of the tomatoes have been incorporated. It is imperative that you stir the tomatoes and the bottom of the skillet on a consistent basis in order to avoid burning either of them. After you have done adding all of the tomatoes, reduce the heat to a low setting and continue to simmer the tomatoes, uncovered, for one hour, or until the volume has fallen by half. This process should be repeated until the tomatoes have reached the desired consistency.