Around 1900, G.F. Mason, manager of the H.J. Heinz Company’s research laboratory, conducted a series of experiments on ketchup. He tinkered with sugar, vinegar, and spices in search of his equivalent of the four-minute mile: a shelf-stable, chemical preservative-free ketchup. Each of his carefully bottled, preservative-free samples kept for about 60 hours until, one by one, the corks popped out and the contents spoiled. Still, Mason was on the verge of a breakthrough: a ketchup that—after achieving victory in an all-out catsup war—would come to dominate America’s taste buds, leaving a wasteland of forgotten ketchup flavors in its wake.

“There were tremendously different ways of producing ketchup historically,” says Andrew Smith, a leading historian of American ketchup and author of Pure Ketchup: A History of America’s National Condiment. “So I suspect that the flavors were widely different from sour to sweet, and [thick to] relatively soft.”

In the early- to mid-1800s, Americans fermented tomato ketchup from a variety of home recipes. The first recorded recipe for a home-fermented tomato catsup was published in 1810, a descendant of British imitations of Asian “cat-sup,” or fermented fish sauce, that the British encountered on colonial voyages. Tomato catsup, which cooks made with ingredients such as apples and anchovies in addition to tomatoes, caught on quickly due to its bright flavor, which livened up an otherwise monotonous American diet. And because it was fermented, it boasted a shelf life of one to seven years.

After the Civil War, companies mass produced, bottled, and sold ketchup to a new class of urban consumers. This ketchup was generally thinner, less sweet, less vinegary, and more tomato-y than present-day ketchup. But while fermentation was a boon for home cooks, it was a liability for manufacturers. Fermentation turned ketchup sour, an increasingly unpopular characteristic as Americans gravitated towards sugar towards the end of the century.

A recipe for Tomato Catsup in the 1817 British cookbook titled <em>Apicius redivivus; or The cook's oracle</em>, by William Kitchiner.
A recipe for Tomato Catsup in the 1817 British cookbook titled Apicius redivivus; or The cook’s oracle, by William Kitchiner. Wellcome Collection / Public Domain

Fermentation also sped up a more dangerous process: Occasionally, bottles of fermenting ketchup would explode. In 1895, the New York Sun reported, “A bottle of catsup exploded on the dinner table of a family at Michigan City, Indiana, recently, and the force knocked all of the dishes off the table.” A 1903 headline in the Saint Paul Globe read, “BOTTLE OF CATSUP EXPLODES IN HER HANDS: Twelve Year Old Emma Setley Is Badly Cut By Flying Glass.”

To protect customers and their bottom lines, ketchup companies embraced chemical preservatives. Smith cites turn-of-the-century studies in California, Connecticut, and Kentucky that found that the majority of commercial ketchup samples contained some form of antiseptic.

Then, in 1883, a man named Dr. Harvey Wiley became chief of the Division of Chemistry of the United States Department of Agriculture, where he fought preservatives with the religious zeal of a man raised evangelical in rural Indiana. Born in 1844 in a log farmhouse, he spent his childhood tending to his family’s crops, then earned chemistry and medical degrees before shifting the Division of Chemistry’s focus to the food-safety problems that plagued the nation.

For the next two decades, he proposed countless Congressional bills on food safety, each of which was killed. But in 1904 he formed “The Poison Squad,” enlisting a group of healthy, young, male volunteers—mostly his colleagues at the Department of Agriculture—to eat all of their meals at work and ingest increasingly large quantities of preservatives. The results read like the last 10 seconds of a modern-day drug commercial: stomach cramps, headaches, sore throat, dizziness, decline in appetite, and loss of weight. Multiple trials stopped when participants became too sick to continue. Sensationalized in the press, “The Poison Squad” shifted public opinion against preservatives.

The Heinz factory, 1954. Henry Heinz was obsessed with sanitation and food purity.
The Heinz factory, 1954. Henry Heinz was obsessed with sanitation and food purity. Trinity Mirror / Mirrorpix / Alamy

At a meeting of the U.S. regional canners associations in 1907, Wiley called for a ban on the use of benzoates, the preservative of choice for the ketchup industry. But executives were not convinced; Wiley couldn’t come up with an alternative to prevent ketchup bottles from souring and, occasionally, exploding.

But then Wiley gained a powerful ally: Henry Heinz, owner of the H.J. Heinz Company. Once a teenage horseradish peddler, by the age of 52 Heinz helmed a condiment firm with offices in London, Antwerp, Sydney, and Bermuda. But it wasn’t until the early 1900s, when he removed preservatives from his ketchup line, that he became the largest tomato-ketchup producer in the world, Smith writes in Pure Ketchup.

Heinz supported Wiley’s food-regulations movement, according to Heinz’s biographer Robert C. Alberts, because of “idealism and noble purpose compounded with self-interest.” Heinz stood at the forefront of food hygiene, so regulations would only help the company command high prices and maintain its reputation.

By 1906, Heinz’s efforts to uncover a benzoate-free ketchup recipe bore fruit. As it turns out, American cooks had long ago figured out another way of halting fermentation (and explosions): carefully boiling ripe tomatoes, adding lots of vinegar, and sanitizing meticulously. Their earlier ketchups “were medium bodied with average acidity,” Smith writes. In 1906, they replaced this ketchup with a shelf-stable, preservative-free ketchup that had twice as much salt, sugar, and vinegar as other commercial ketchups, and a full body from perfectly ripe, carefully cooked tomatoes, producing 12 million bottles of it in the next two years with little spoilage. A few years later, after a woman in Pennsylvania sent Heinz a dozen bottles of her homemade, tastier, better-looking, benzoate-free ketchup, they adopted her recipe, which was also sweet, vinegary, and thick.

A Heinz advertisement from 1938.
A Heinz advertisement from 1938. John Frost Newspapers / Alamy

Thanks in part to high-quality ingredients, Heinz’s new tomato ketchup cost two to three times more than its competitors. But the price increase also paid for the largest advertising campaign the industry had ever seen. In one of several advertisements to grocers, “Heinz stated that grocers should ‘get rid of any chemically preserved foods’ before they were confiscated by the government,” Smith writes. Heinz took out a two-page spread in the Saturday Evening Post that shouted, in block letters: “WARNING! THE U.S. Gov’t Says benzoate of Soda in Foods Produces Injury to Digestion and Health.”

In response to Heinz and Wiley, a cabal of ketchup companies formed a fierce pro-benzoate lobby. In meetings with President Theodore Roosevelt, they argued that an anti-benzoate law would destroy the ketchup industry. American grocery stores stocked few preservative-free, shelf-stable ketchups, so the lobby said that Heinz’s claims were impossible, and they spread rumors about ketchup bottles exploding without preservatives. According to Smith, an industry journal reported that “a priest in Washington, Pennsylvania, ‘was hauled across the room and struck his head against the door’ because of an explosion caused by the lack of preservatives.”

In 1907, Wiley hired chemists Arvil and Katherine Bitting to make ketchup without preservatives and offer scientific backing to Heinz’s claims. Since homemade ketchup had a longer shelf life than manufactured bottles, the Bittings studied recipes from cookbooks, magazines, and journals, and found that homemade ketchup contained far more vinegar, sugar, and spices than the 1,600 commercial ketchup bottles they analyzed. After some tinkering, they determined that ketchup could keep indefinitely if it was boiled until it thickened, made with ripe tomatoes and lots of vinegar, and handled and canned in a sanitary manner.

Heinz cited Wiley’s and the Bittings’ research in his ads as he continued a full court press on consumers, grocers, and politicians. But the benzoate lobby fought for its life. At one point, industry journals published unsubstantiated reports that Wiley got into a bickering match at a hotel after being served chemically preserved ketchup, and they called for his firing. But Roosevelt stood by him.

By 1911, Heinz had won the fight. His pricey, thick, sugary, vinegary ketchup dominated the market, and it continues to do so today. “[Heinz was] at the right place, at the right time, with the right product, with good promotion,” says Smith. “People got frightened of ketchup … and if you want to have ketchup and you want to be safe you go for Heinz.”

In 1908, a board of scientists created by President Roosevelt ruled that benzoate of soda was harmless if consumed in quantities of less than a half of a gram per day. But this didn’t matter: Wiley and Heinz continued their campaign on public opinion, and Americans soured on preservatives. By 1915, Smith writes, most major ketchup companies stopped using them altogether, and those that didn’t lost many of their customers. It helped, too, that the thick consistency of Heinz’s preservative-free ketchup allowed it to cling tenaciously to the hot dogs, hamburgers, and french fries that swept the nation in the 1900s.

"Blue Label" Tomato Ketchup claimed that without preservatives, the company would have to boil away the tomato flavor that made its ketchup special.
“Blue Label” Tomato Ketchup claimed that without preservatives, the company would have to boil away the tomato flavor that made its ketchup special. The American Monthly Review of Reviews / Public Domain

At the time, Heinz’s victory secured cleaner ketchup with higher-quality ingredients for Americans. Many companies had used benzoates to hide poor sanitation and low-quality tomatoes. Ketchup was often made from leftover tomato trimmings that were stored poorly and then bottled with a heavy dose of benzoate, which also covered up factories’ shoddy sanitization practices that would otherwise breed mold and bacteria. This had allowed companies to sell at a lower price, Smith writes, but at a cost to consumer safety. As time went on, though, food inspectors were better able to detect low-quality or contaminated ketchup, with our without benzoates, prompting more companies to drop them.

But Smith contends that this triumph came at a price: a mass extinction event for the once diverse ecosystem of ketchup flavors. The sugar, vinegar, and heavy boiling required to make preservative-free ketchup overwhelmed the condiment’s once myriad flavors. During the ketchup war, Blue Label Ketchup said that without benzoates they would have to cook the tomato flavor out of their ketchup. Smith writes supportively, citing testimony from a ketchup maker that benzoated ketchups “certainly had a better flavor than anything [preservative-free] on the market today.”

Today, a few craft-ketchup makers are experimenting with the condiment’s sweetness, acidity, and tomato taste. Sir Kensington’s sells a popular ketchup that is chunkier, with more of a tomato taste than Heinz’s classic flavor. Chef Jose Andrés pulled 1800s recipes from archived cookbooks to make yellow tomato ketchups at America Eats Tavern, a pop-up that has since closed. And a company called Molonay Tubilderborst claims to revive a low-sugar, 19th-century recipe with its Savory Ketchup. I tried to procure a bottle, but they only stock in the West Coast and Texas, and Amazon had sold out. For a taste of ketchup’s Land Before Time, I’ll just have to make catsup at home.

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