Cans of Coca Cola for sale is displayed at a grocery store in Phoenix, Arizona, February 9, 2011. REUTERS/Joshua Lott

For 125 years, Coke’s secret recipe has remained one of the most heavily guarded trade secrets in the world. Now a group of accidental soda sleuths say they’ve stumbled across a list of its ingredients.

Producers of the radio program This American Life came across an article on the history of Coca-Cola in an old copy of the Atlanta Journal-Constitution, Coca-Cola’s hometown newspaper. Published on page 2B on February 18, 1979, the article received little attention at the time. But, producers say, that’s because no one realized the photo used to illustrate the story is a hand-written copy of John Pemberton’s original recipe, jotted down by a friend in a leather-bound recipe book of ointments and medicines, and passed down by friends and family for generations.

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The long story of Coke’s secret formula begins with Pemberton, a veteran from Georgia who emerged from the Civil War with a morphine addiction. Hoping to cure his ailment, he dreamed up Pemberton’s French Wine Coca, a brew that included kola nut and coca wine. But in 1886, as Atlanta passed prohibition legislation, he reformulated the drink without alcohol, renamed it Coca-Cola, and began selling it in Georgia pharmacies.

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Asa Candler, an early president of the Coca-Cola company who bought the formula in 1887, worried rivals would obtain the recipe so insisted no one ever write it down again. Staff removed all labels from ingredient containers and identified them by sight and smell only. Candler even went through the company mail so he could shred invoices that employees might attempt to sell to other drink makers.

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If the radio program’s producers are right, Candler and other executives were too late: the book of remedies with the copy of the Coke recipe had already started its travels. This American Life tracked down the book to a widow in Griffin, Georgia, who says her husband was fishing buddies with the Atlanta Journal-Constitution writer. It’s now in a bank vault, too.

And while companies like Pepsi have deduced the general ingredients on their own, none have unlocked the “Merchandise 7X flavoring” that gives Coke its unique taste and bubbly burn. “The company has always said, and as far as I know it’s true, that at any given time only two people know how to mix the 7X flavoring ingredient,” Mark Pendergrast, historian and author of For God, Country and Coke told This American Life. “Those two people never travel on the same plane in case it crashes; it’s this carefully passed-on secret ritual and the formula is kept in a bank vault.”

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The recipe:

Fluid extract of Coca: 3 drams USP

Citric acid: 3 oz

Caffeine: 1 oz

Sugar: 30 (unclear quantity)

Water: 2.5 gal

Lime juice: 2 pints, 1 quart

Vanilla: 1 oz

Caramel: 1.5 oz or more for color



The secret 7X flavor (use 2 oz of flavor to 5 gals syrup):

Alcohol: 8 oz

Orange oil: 20 drops

Lemon oil: 30 drops

Nutmeg oil: 10 drops

Coriander: 5 drops

Neroli: 10 drops

Cinnamon: 10 drops

The This American Life team enlisted experts and ordinary citizens alike to taste-test the original formula. It was pretty close — some people couldn’t differentiate it from the real thing — but the radio show couldn’t hit the nail on the head. And no matter what, they’ll never quite achieve the level of marketing that has made Coca-Cola so beloved.

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