The U.S. public radio program ‘This American Life’ has revealed what it believes is the original recipe for Coca-Cola. The show found what appeared to be a copy of the famously guarded trade secret in a newspaper column published in the Atlanta Journal and Constitution on February 18, 1979.

Then they spoke with historian Mark Pendergrast, who had discovered what he believed was a version of Coca-Cola’s original formula decades before while doing research in the company’s own archives.  (He published that version of the recipe in his 1993 book on Coke.) The formulas were essentially identical. Host Ira Glass read the full version on ‘This American Life’’s radio broadcast which is heard by more than 1.8 million people on over 500 public radio stations across the country (plus, on the show’s podcast with an audience of 600,000).

Photo: This American Life

As for the most famous ingredient of Coca-Cola, the first item listed in the recipe is «F.E. Coca,» which stands for fluid extract of coca, which contains cocaine—it was in the soda until 1903 (coca extract is still an ingredient in Coca-Cola). It’s decocainized under federal supervision at a company called Stepan in New Jersey.

Since the only way to be sure if the recipe really was for Coca-Cola would be to make a batch, ‘This American Life’ asked with Seattle-based Jones Soda, to do just that.  The recipe has several known differences with Coca-Cola’s current formula. It uses sugar instead of the current sweetener, high fructose corn syrup. It uses citric acid, where current Coca-Cola—like most modern sodas—is known to use phosphoric acid. It uses lime juice; the current recipe is believed to use lime oil.

Photo: This American Life

Ultimately, however, the team was able to make a version of the recipe that fooled one expert—and to their surprise, was preferred 6-to-4 in an informal taste test in a Brooklyn supermarket.

In keeping with its past statements about the formula, the company denies the recipe’s authenticity, and the company’s archivist, Phil Mooney, said he did not believe the recipe was beverage’s original formula.