There is a wide variety of canned tomatoes available to us at the grocery store. Some are diced, others pureed, while whole peeled tomatoes remain a favorite among chefs and home cooks. Both San Marzano and Roma tomatoes are among the most common types used for canning.

So what is the difference between these two tomatoes? Well, the first thing to recognize is their similar composition: Both have a higher flesh-to-juice ratio, which means that it contains a significantly smaller amount of that gelatinous and watery seed at the center. Thus, both are considered plum tomatoes, a type of tomato used to make sauces, per On the Gas.