Rabbi Tobias Geffen lived for 100 years: He was born in 1870 and died in 1970. For 60 odd years of his life he lived in Atlanta, Georgia, the hometown of the Coca-Cola Company. Geffen published a handful of books and was considered an important halakhic arbiter, but more than anything else he is identified with a responsum he issued in 1935 − stating that Coca-Cola is kosher and can also be drunk during Passover.

The story of this affair appears in a biography of the rabbi published by his granddaughter, Ruth Adler. Geffen was one of the only people who had the privilege of learning the secret formula for the drink. He apparently undertook to keep the recipe a secret, and referred to two of the beverage’s original ingredients by codenames: “moris” (a Roman-era seasoning) and “anigron” (a food mentioned in the Talmud). He identified the former as a type of glycerine oil made from meat and another, nonkosher substance. Anigron was a substance derived from grains, and therefore not kosher for Passover.

In order to have Geffen certify the drink kosher for consumption throughout the year, the Coca-Cola Company switched to manufacturing the “moris” from vegetable sources, and the “anigron” grains from cane sugar.