The Real Thing: How Coke Became Kosher

Rabbi Tobias Geffen, who ruled on Coke’s kosher status. (Cuba Family Archives of the Breman Museum)

Rabbi Tobias Geffen, who ruled on Coke’s kosher status. (Cuba Family Archives of the Breman Museum)

Hard to Swallow

Jews widely drank Coke, and Coca-Cola actively sought Jewish consumers. But was the drink kosher? Answering that seemingly straightforward question led to Coca-Cola becoming the first nationally prominent company to adapt its product contents for kosher requirements. Creating a kosher Coke established important precedents for the future expansion of kosher-certified products.

Rabbi Geffen was the principal figure in the development of kosher Coke. As a leading figure in Atlanta’s Jewish community since his arrival in 1910 as chief rabbi of Shearith Israel, Geffen was well-positioned to secure Coca-Cola’s cooperation in this investigation. He even persuaded the company to reveal to him, in strictest confidence, the drink’s famed secret ingredient.

His investigation into Coke’s contents determined that a seemingly innocuous chemical known as glycerin was unacceptable under kosher law. This slightly sweet, syrupy liquid was and is widely used to diffuse flavor—such as Coke’s secret ingredient—in beverages, keep cakes moist and fresh, prevent ice crystals from forming in ice cream, and ensure that breads are not too crumbly. Why was this miracle of modern science a problem? Geffen learned that glycerin was a by-product of soap manufacturing, which used fatty oils generated from meat processing, including from pigs and cattle that were not kosher slaughtered. Yet glycerin itself did not exist in nature, independent of such manufacturing; moreover, glycerin created from vegetable-based fatty oils was chemically identical to glycerin derived from pork fat.

In a ruling that had immense implications Geffen held that the kosher status of glycerin was dependent on its source. In other words, if glycerin originated from a nonkosher animal, it wasn’t kosher; if it came from vegetable sources, it could be kosher. Geffen’s ruling would become the standard that Orthodox rabbis used to evaluate the kosher status of all questionable ingredients in food, such as spices, food colors, and preservatives.

Geffen also had to address the implications of the infinitesimal amount of glycerin in Coke—less than 0.01% of its volume. Did such a small amount fall under the well-established kosher principle of bitul (nullification), meant to accommodate mistakes made while cooking, such as inadvertently dropping a pat of butter into beef stew. If the butter amounted to less than one-sixtieth of the volume of the stew, then the butter was bitul b'shishim (nullified in the sixtieth), and the stew was still kosher, even though it contained a small amount of milk.

Since glycerin composed far less than one-sixtieth of the volume of Coke, Geffen had to consider whether it was bitul b'shishim—nullified—rendering Coke kosher. He held that it wasn’t nullified since the traditional concept of bitul only applied to accidents, while the use of glycerin in Coke was deliberate. As a result Geffen determined that conventional Coke was not permissible for observant Jews
to drink.

Geffen’s ruling had far broader implications; his extension of traditional kosher law to modern food meant that every ingredient, no matter how minute, now had to be kosher. If Geffen had ruled differently, he might have opened the door to “kosher” food containing prohibited chemicals.

Coke’s response to Geffen also set a very important precedent. While its chemists and executives may have had a hard time understanding Geffen’s insistence on differentiating between glycerin made from animal fats and glycerin made from vegetable oils, they nonetheless accepted his ruling. And since they did indeed want to eliminate any obstacles to reaching new markets, including observant Jews, the company went about finding a way to accommodate Geffen’s objections.

The company asked Procter and Gamble, its glycerin supplier, if they could deliver glycerin derived from vegetable fats. Procter and Gamble, for its part, had been making Crisco shortening from cottonseed oil for over 20 years and was well aware of its use by observant Jewish consumers. Consequently, the company fully understood Coca-Cola’s request and agreed to supply glycerin made from cottonseed oil. To document its compliance with kosher requirements, Coke collected affidavits certifying that the glycerin used in special batches of Coke syrup came from cottonseed oil. With this evidence in hand Geffen issued a teshuva (ruling) in 1935 that the reformulated Coke did indeed meet Jewish dietary requirements. Observant Jews could at last relax with their bottle of Coca-Cola in hand.

Or so they thought. . .