The brief and slightly baffling history of ketchup

I was standing in a supermarket aisle recently, staring at a bottle of Heinz tomato ketchup, when it occurred to me that I had absolutely no idea what "ketchup" actually meant.

It is one of those words we say without thinking, like "Google" or "weekend," assuming it has always existed in its current form. We squeeze the red stuff onto fries, burgers, and—if you are a particularly adventurous toddler—scrambled eggs, never pausing to consider why a sauce made almost entirely of tomatoes and sugar has a name that sounds vaguely like a sneeze.

If you were to ask me where ketchup came from, I probably would have guessed it was invented by an American named Chuck in 1950 to make hot dogs more palatable. I would have been wrong. As it turns out, the history of ketchup is a long, winding, and frankly bizarre journey that involves fermenting fish guts in China, British sailors getting confused, and a prolonged period where people were terrified that tomatoes were going to kill them.

It is a story of global trade, chemical experimentation, and the human desire to make dry meat taste slightly less like shoe leather. And it starts, as all good culinary stories do, with something that smells terrible.

The accidental origins of the fermented fish sauce that started it all

To understand ketchup, you have to abandon everything you think you know about it. Forget tomatoes. Forget the colour red. Forget the impossible-to-open glass bottle that requires you to smack the bottom like you are burping a newborn.

The original ancestor of our beloved condiment was born in southern China, specifically the Fujian province, likely around the 17th century (though some historians argue it goes back much further). It wasn’t a thick paste; it was a thin, pungent brine made from pickled fish and shellfish.

The locals called it kê-tsiap (or kôe-chiap, depending on which dialect of Hokkien you prefer). Roughly translated, it means "brine of pickled fish." It was essentially fish sauce—the funky, salty, umami-rich liquid that you splash into a stir-fry today.

The British arrive and get confused

Now, imagine you are a British sailor in the late 1600s. You have spent months at sea eating hardtack biscuits that double as masonry bricks and salted beef that has the texture of a cricket bat. You dock in Southeast Asia—perhaps Malaysia or Indonesia, where Chinese traders had spread this kê-tsiap—and you taste this magical salty liquid. It adds flavor! It masks the taste of rot! It is a miracle!

Naturally, the sailors wanted to bring it home. But there was a problem. You couldn't exactly grow Asian fish fermenting in the sun back in chilly, rainy England. So, in classic British fashion, they decided to improvise. They took the name—anglicizing it to "catchup" or "catsup"—and completely butchered the recipe.

Since they didn't have the right fish or the right climate for fermentation, they started making "ketchup" out of literally anything they could find that seemed savory and preservable. This led to what I like to call the Dark Ages of Condiments.

A detour through the dark ages of walnut and mushroom ketchups

If you open an English cookbook from the 18th century, you will find recipes for "ketchup" that read less like culinary instructions and more like a witch's potion.

Cooks were desperate to recreate that savory, umami kick of the original Asian fish sauce. They tried everything. There were recipes for oyster ketchup (which at least made sense), anchovy ketchup, elderberry ketchup, and even beer ketchup. But the two heavyweight champions of this era were walnuts and mushrooms.

The reign of the walnut

Jane Austen, that chronicler of polite society and repressed longing, was apparently a fan of walnut ketchup. Her family had a recipe for it. To make it, you had to take green walnuts—before the hard shell formed—pound them into a black sludge, and let them steep in vinegar and spices for weeks.

The result was a dark, thin, astringent liquid that tasted like Worcestershire sauce had a bad day. It was incredibly popular. It lasted forever on the shelf, which was the primary requirement for food in an era before refrigeration, and it could make a piece of boiled mutton taste vaguely interesting.

Mushroom madness

Then there was mushroom ketchup. This was the dominant form of ketchup in the UK for over a century. You would take whole mushrooms, pack them in salt until they wept all their liquid, and then boil that liquid with spices like mace, cloves, and pepper.

If you go to a very traditional grocery store in England today, you can still find a bottle of "Geo. Watkins Mushroom Ketchup." I bought one once, out of curiosity. It tastes exactly like you would expect: like salty, liquid mushrooms. It is not something you want to put on a fry.

So, for over a hundred years, when someone in the English-speaking world asked for "ketchup," they weren't expecting a red dollop of tomato sweetness. They were expecting a thin, brown, salty splash of fungus juice. It was a bleak time.

How the tomato went from a suspected poison to a culinary hero

You might be wondering: where were the tomatoes? The tomato is native to the Americas, and by the 18th century, it had made its way to Europe. Why wasn't anyone mashing them up and putting them in a bottle?

The answer is simple: fear.

For a long time, Europeans and North American colonists were deeply suspicious of the tomato. It belongs to the nightshade family, which includes some genuinely nasty plants like belladonna and mandrake. Because of this family resemblance, and perhaps because the bright red fruit looked a bit too cheerful to be trusted, many people believed tomatoes were poisonous.

There is a wonderful (though likely apocryphal) legend that rich Europeans would eat off pewter plates, the acid from the tomato would leach lead from the plate, the diner would get lead poisoning and die, and the tomato would get the blame. Whether that is true or not, the "poison apple" reputation stuck.

The brave James Mease

It wasn't until 1812 that a scientist in Philadelphia named James Mease decided to throw caution to the wind. He published the first known recipe for tomato ketchup. He called tomatoes "love apples," which is charming, and his recipe involved spices and brandy, which is even more charming.

However, Mease’s ketchup wasn't the stable, thick sauce we know today. It was watery, fermented, and spoiled rapidly. Because the tomato season was short, makers had to figure out how to preserve the pulp for the rest of the year.

This led to a new problem. To keep the tomato goop from turning into a fuzzy science experiment, manufacturers started adding chemicals. And not nice chemicals. We are talking about things like coal tar (to keep it red) and sodium benzoate (to keep it from rotting).

By the late 19th century, commercial ketchup was a filthy business. It was often made from the sweepings of cannery floors—rotten tomatoes that were unfit for canning were scooped up, mashed, filled with preservatives to kill the bacteria, and dyed red to hide the grey/brown color of the decay. It was, effectively, embalmed filth.

The industrial revolution and the quest for the perfect red sauce

Enter Henry J. Heinz.

If there is a patron saint of condiments, it is Henry. In 1876, he launched his tomato ketchup in a clear glass bottle. This was a revolutionary flex. Most manufacturers used brown or opaque bottles to hide the impurities and sludge floating in their sauce. Heinz used clear glass to show off that his product was actually red and didn't contain any visible insect parts.

But the real game-changer came a few decades later, thanks to a crusading chemist named Harvey Washington Wiley. Wiley was obsessed with food safety (a novel concept at the time) and formed a "Poison Squad"—a group of young men who volunteered to eat food laced with common preservatives like borax and formaldehyde to see if it would kill them. Spoiler: it made them very sick.

Wiley wanted to ban sodium benzoate, the preservative used in ketchup. The industry screamed that it was impossible to make ketchup without it—the bottles would explode! The ketchup would rot!

The recipe that changed everything

Heinz, seeing a marketing opportunity, decided to side with the scientists. He tasked his food technologists with creating a preservative-free ketchup. They discovered that if you used ripe tomatoes (which have more pectin) instead of rotten leftovers, and significantly increased the amount of vinegar and sugar, the resulting acid and sugar content would naturally preserve the sauce.

The result was thicker, sweeter, and more acidic than any ketchup that had come before. It was the taste profile we know today. It didn't rot, it didn't kill you, and it tasted fantastic on a hamburger.

This new recipe killed off the competition. The walnut and mushroom ketchups faded into obscurity, and the "tomato" part of "tomato ketchup" became so standard that we eventually stopped saying "tomato" altogether.

Why ketchup remains a baffling yet beloved household staple today

So here we are. We took a Chinese fish brine, stripped it of the fish, added British mushrooms, replaced the mushrooms with American "poison apples," filled it with sugar and vinegar to stop it from exploding, and called it the national condiment of the United States.

It is a strange journey for a sauce. But in a way, it makes perfect sense. Ketchup is the ultimate survivor. It adapted to every culture it touched, changing its ingredients to suit local tastes and available crops, while keeping its core identity as a savory, shelf-stable flavor booster.

Today, ketchup is scientifically designed to hit every taste receptor on your tongue—salt, sweet, sour, bitter, and umami. It is arguably the most perfect food product ever engineered.

I still don't recommend putting it on a steak, though. That is just wrong.

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