Marinara sauce is a quick sauce. Ketchup, on the other hand, is a more complex matter. Marinara sauce is a quick sauce, seasoned only with garlic, chopped red pepper and basil. It's best when made with whole San Marzano tomatoes or plums, shredded by hand or passed through a food mill.
The marinara can be left in pieces; the texture of the finished sauce is quite loose and the flavor is that of fresh tomatoes. Tomato sauce, on the other hand, is more complex, since it starts with mashed tomatoes seasoned with onions, carrots, celery and bay leaves, and is left to simmer until it thickens and has a rich flavor. Sometimes a piece of fresh pork is added for added flavor. The flavor is sweeter and more complex.
While the two sauces share many ingredients, the main difference is in the consistency and depth of flavor. Marinara is brighter, thinner and has more tomato flavor than ketchup. Tomato sauce is thicker, creamier and has a certain resemblance to sauce, which is why some Italians call it “Sunday sauce”. Because the two sauces look similar (and can sometimes even taste similar), we often use the names marinara and tomato interchangeably.
However, the two sauces are not the same thing. According to Taste of Home, marinara sauce cooks much faster than tomato sauce (often less than an hour) and has a less complex flavor profile that usually consists simply of tomatoes, garlic and oregano. Tomato sauce, on the other hand, requires hours of slow cooking and is made with more abundant ingredients, which often include a creamy base of roux, meat, and other vegetables and various herbs. As a result, ketchup tends to be much thicker and more robust than its marinated counterpart.
In this sense, marinara sauce can also be considered a pasta sauce, in addition to pesto sauce, Bolognese sauce, Alfredo sauce and many more. In contrast to the beautiful fusion of flavor of pasta sauce, marinara sauce stimulates taste buds by leaving room for individual flavors to shine through. If you are going to prepare stuffed pasta such as tortellini, manicotti or pansotti, you have to try the alla Norma sauce. A good starting point is to analyze the subtle differences between marinara and tomato sauce, the two encompassed by most tomato-based sauces.
The sauce acquires its characteristic flavor through the addition of garlic, crushed red pepper flakes and herbs such as basil and oregano. Think of the classic Marcella Hazan sauce, which is more like tikka masala than something you'd find at your local Italian-American restaurant. Depending on your definition of ketchup, marinara sauce may not be similar to ketchup or is one of many types of tomato sauces. Many people consider Rao's Homemade to be one of the best-tasting canned marinara sauces on the market.
However, in the United States, pasta sauce (or spaghetti sauce) is culinary jargon that betrays the tomato-based sauce added to your favorite types of pasta. In addition to tomatoes, this delicious Sicilian sauce also includes juicy eggplants and creamy ricotta cheese in its ingredient. If you usually cover spaghetti with a tomato-based condiment, then you can't go wrong with the marinara or pasta sauce. Butter or animal fat (traditionally salted pork or bacon) is often used instead of or in addition to olive oil, with flour added to help thicken the sauce.
That said, some Americanized variations of this sauce also include Parmesan cheese, while authentic marinara sauce should not contain meat, anchovies, or any dairy products.
