ketchup or tomato paste

Ketchup is a sweet, tangy condiment made from tomatoes, vinegar, sugar, and spices that is cooked down into a thick, pourable paste. The ingredient originated in China as a fermented fish sauce called ke-tsiap, which was adapted by British colonists and eventually became the tomato-based condiment popularized in America during the 19th century. Modern ketchup typically contains tomato concentrate or fresh tomatoes, distilled vinegar, high fructose corn syrup or sugar, salt, onion powder, garlic powder, and spices such as allspice, cinnamon, and cloves. The result is a smooth, glossy condiment with a balanced sweet-sour-savory flavor profile and a deep red color.

Tomato paste, by contrast, is a concentrated form of tomatoes made by cooking tomatoes for hours and straining out seeds and skins, then reducing the liquid further to create a thick, intensely flavored concentrate. It contains minimal added ingredients beyond salt and sometimes citric acid as a preservative. Tomato paste offers a more robust, umami-forward tomato flavor without the sweetness of ketchup and serves as a building block for sauces rather than a finished condiment.

Ketchup functions primarily as a condiment and finishing sauce, served alongside hamburgers, hot dogs, french fries, and grilled meats in American cuisine. It is also incorporated into recipes such as meatloaf, baked beans, and Heinz-style soups. The condiment's sweet-acidic profile makes it suitable for glazing, dipping, and adding to composite sauces.

Tomato paste is a foundational ingredient in Italian, Spanish, and Mediterranean cuisines, used to build depth in pasta sauces, soups, stews, and braises. It concentrates the umami compounds of tomatoes and is often combined with aromatics, oils, and herbs to create complex sauces. A small amount of tomato paste can significantly deepen the tomato flavor in chili, goulash, and other slow-cooked dishes without the liquid content of crushed or whole tomatoes.