Although the two sauces share many ingredients, the main difference is in the consistency and depth of the 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”. Marinara sauce and ketchup are often used interchangeably and for clear reasons; the two look and taste quite similar to each other.
But those nuances in their textures, cooking processes, and flavor profiles are the same things that separate these two sauces into different categories. And make each one better adapt to different recipes. But before delving into their differences, let's talk about what ketchup and marinara sauce actually are. 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. 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, often including 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.
Marinara sauce is much lighter and simpler compared to pasta sauce. Marinara usually uses only tomato, olive oil and garlic, making it less complex than pasta sauce. In addition, marinara takes less time to cook, while pasta sauce may have meat that extends its cooking time. Since both sauces are made with tomatoes as a base, it is possible to replace the marinara with tomato sauce.
That said, marinara isn't as heavy or flavorful as ketchup, so the flavor and texture of the finished dish will be very different. According to the pasta sauce company Paesana, marinara sauce is prepared by combining olive oil, garlic and basil with whole peeled tomatoes (preferably of the San Marzano type). So when it comes down to that, how are the two really different? In short, ketchup has much more depth and complexity than marinara sauce, plus a longer list of ingredients. The common idea is that this sauce was a staple food that seafaring merchants normally consumed, since it was a simple sauce that required little preparation time.
It's best to think of marinara sauce as a basic form of tomato sauce, especially since its flavor notes, cooking time and ingredient list are short and sweet, according to Paesana. We often see that the terms “ketchup” and “marinara” are used interchangeably on supermarket sauce jars. Pizza is a great example of this, as marinara sauce is often used to keep ingredients in place while giving a light tomato flavor. Or you can take out a bag of French fries or French fries for a movie night and dip it in marinara for an extra touch of flavor.
Most recipes start with a soffrito made up of chopped carrots, onions and celery, according to Cooks Info, with ingredients such as olive oil, garlic, butter and herbs added (besides tomato, of course) to give the sauce depth and flavor. Spaghetti sauce is usually served with any variety of cooked pasta, such as lasagna, spaghetti or manicotti, and usually contains meat, vegetables, spices and condiments. There is also a French version of this sauce, called tomato sauce, which according to the Escoffier School of Culinary Arts is made with roux. Spaghetti usually uses pasta sauce, since they are commonly made with meat (meatballs and spaghetti are a classic combination).