Soup is one of those foods that is, in many cases, painfully mediocre. When you hear the word “soup,” you probably think of a pitiful, light broth from a can—but soup can be so much more. Soup is like a blank canvas; it is merely a unique medium that can be infused with endless flavor—many factors go into making great soup.
Let’s start by examining the classic tomato soup—a staple by American standards. Many fail to realize that tomato soup is not much different than tomato sauce. There is typically no stock used in tomato soup, and the main component is pureed tomatoes. The base flavor profile can be changed in a variety of ways such as, but not limited to, roasting the tomatoes, removing their skins, and most importantly, selecting specific tomato varieties: Roma, Cherry, Plum, Beefsteak, Heirloom, and many others.
If you are making tomato soup with only one variety of fresh tomatoes, I firmly believe that Roma tomatoes are the best option. They are a robust variety that takes well to roasting, blanching, etc.; additionally, they are fairly accessible and consistent—at least by tomatoes’ generally shitty standard of quality.
What do I mean by this? — Over time, genetic modification has plagued the quality of tomatoes. Following the introduction of the first genetically modified fruit in 1994, the Flavr Savr Tomato, GMOs and tomatoes have become synonymous. Consequently, the seeds of tomatoes, even ones labeled as “organic”, are primarily tainted. The available seed inventory of tomatoes is primarily plagued by commercialism in the form of excessive genetic modification. Once again, quality, as it does in many areas, fell to the interests of preservation, commercially attractive coloration, and size. The once tiny berries of Mesoamerica transformed into large, comically red fruits we call tomatoes.
Due to this tragedy, there are few sources of relatively good quality tomatoes. I would say that one of the best sources available in most American grocery stores is, surprisingly, canned tomatoes. Be aware, this does not mean any canned tomato—specifically, whole peeled San Marzano (Italian) or Bianco diNapoli (Californian) plum tomatoes. The latter will certainly be harder to find, but I believe that, if you can, it is the better option for a sweeter and more vibrant soup. You may wonder why this is the case, and to be frank, I am not sure of all the reasons why; however, I do know that they are canned right after they are harvested, so they do not have as much time to lose various flavor-packed nutrients. Furthermore, canning tomatoes increase their shelf life without the use of preservatives; this provides quality tomato access to people who would otherwise be without.
Obviously, canned tomatoes are not the end-all-be-all substitute for fresh tomatoes—they do not have the right texture for many uses. However, if you are going to puree the tomatoes anyway, the texture is negligible. So, unless you have a particularly good source of tomatoes, meaning most Americans not living in California, please use canned tomatoes for soups and sauces—trust me, you will notice a difference.