How Ketchup Works

What's in Ketchup?

Homemade ketchup sits on a spoon. Zoryana Ivchenko/Getty Images

How about topping your next hamburger with the stomach, intestine and bladder of a yellow fish? Those were the ingredients in the first ketchup recipe ever recorded. Because back in ketchup's early days (the 6th century), in China's Fujian province, the sauce was a bitter pickled fish brine [sources: Lewis, Bratskeir].

Luckily, that recipe changed considerably as the original ke-tchup traveled around the globe. America's first printed ketchup recipe, published in 1758 in "The Compleat Housewife," was created from anchovies, cloves, ginger and pepper. The sauce was actually more like a chutney [source: Gandhi].


In the early 1800s, Americans began experimenting with their own homemade ketchups, preparing them with ingredients like shallots, oysters, lemons, walnuts, elderberries, mushrooms and beer. (Fun fact: Author Jane Austen was supposedly a fan of walnut ketchup.) The first-known tomato-based ketchup recipe was published in 1812, but the red version really became popular after the Civil War. In 1871, Henry J. Heinz began selling tomato ketchup. He also created the iconic octagon-sided ketchup bottle in 1890 [source: Heinz]. Now, you can only find them in restaurants.

A Heinz Ketchup bottle.
A Heinz Ketchup bottle. Credit: Heinz

Today's commercial ketchups typically contain tomatoes, vinegar, salt, sweeteners, onion powder, spice and natural flavors. That may sound harmless, but ketchup contains a lot of sugar, and often in the form of high fructose corn syrup and corn syrup. Some ketchups today have swapped sugar for the corn syrups and contain less salt to meet consumer demands. Still, one tablespoon of ketchup contains about 15 to 20 calories [source: Carr].

If you'd like to make your own, it's not that difficult. But using fresh, ripe tomatoes is key to creating a tasty sauce. One top-rated ketchup recipe, published on The New York Times' website, calls for tomatoes, red wine vinegar, dark brown sugar, salt, black pepper and Worcestershire sauce. Supposedly the result is a zesty sauce akin to the classic Heinz recipe.