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How Was the Top-Secret Coke Formula Determined to Be Kosher?

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Few products in history can match the mythology and ubiquity of Coca-Cola. Started in 1886 by John S. Pemberton, a pharmacist and former Confederate soldier, the company has changed hands several times in its existence. Yet the storied formula of its marquee offering has remained an impressively guarded company secret known only to a few top executives. Owing to some dubious health claims and an innovative marketing strategy—it’s believed to have been the first product to employ coupons—Americans fell fast and hard for Coke.

Of course, no love affair is without its rough patches, and, by the 1930s, Coke’s inscrutability found itself at odds with a niche, but rapidly growing, consumer base: Orthodox Jewish immigrants whose dietary restrictions prevented them from consuming anything that didn’t meet rigid rabbinical guidelines. So, how was Coke ultimately kashered while keeping its prized formula a secret? Through compromise and chemistry.


In 1935, new world consumerism and old world mores found an unlikely intersection in Atlanta, Coca-Cola’s headquarters. Approaching its 50th birthday, Coke was a national icon, available at nearly every soda fountain in the country. Millions of gallons were being consumed every year, many of those by immigrants who, by that point, had settled all over the country. Enter Tobias Geffen, a Lithuanian Jew who’d moved to Atlanta 25 years prior to lead Congregation Shearith Israel. Seeing that Rabbi Geffen and Coke were essentially neighbors, rabbinic leaders from around the country began to write him, asking if it was permissible for Orthodox Jews to drink Coke based on what he knew about the ingredients. Unsure how to reply and unaware of Coke’s staunch protection of their formula, he contacted the company and asked for a list of the ingredients.

Amazingly, Coke agreed to share the list on the condition that Rabbi Geffen swear the formula to secrecy. They didn’t, however, include the amounts of each component, which is as important as the ingredients themselves. Upon examination, Rabbi Geffen noticed that it included glycerin, used as a sweetener, derived from non-kosher beef tallow. Though it was present in small enough amounts to technically meet kosher standards, Geffen decided that, since it was added intentionally and not as a necessary byproduct, he couldn’t sign off on certification. After hearing his ruling, Coke chemists set out to find a tallow substitute that would meet kosher standards without changing the taste. They honed in on a glycerin made from cottonseed and coconut oil that left both parties satisfied, and Geffen gave it his approval.

Still, one problem remained. At Passover, an even stricter set of dietary constraints are followed, and the miniscule amounts of alcohol in Coke from grain kernels were chametz—a Passover no-no. Coke’s scientists hit the lab once again and found that sweeteners from beet and cane sugars could be substituted for grain sweeteners without affecting the taste. Ever since, in the weeks leading up to Passover, Coca-Cola releases a modified formula using cane sugar instead of high fructose corn syrup (just like the much sought-after Mexican Coke), which is bottled with a yellow cap to signify it’s kosher for Pesach.


Discounting a single disastrous reformulation in the mid-80s, Coke’s taste has remained remarkably consistent over the past century, which, more than marketing or ubiquity, is likely the greatest contributor to its longevity. Even so, the drink is still subject to periodic rabbinical review to uphold its kosher status. Coca-Cola executives are not quite as forthcoming with its secrets as they were in Rabbi Geffen’s time, though. Now, the company simply provides an overstuffed list of ingredients for approval, all of which are known to be kosher, but only a handful of which are actually used in the formula.

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Big Questions
Why Don't We Eat Turkey Tails?
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Turkey sandwiches. Turkey soup. Roasted turkey. This year, Americans will consume roughly 245 million birds, with 46 million being prepared and presented on Thanksgiving. What we don’t eat will be repurposed into leftovers.

But there’s one part of the turkey that virtually no family will have on their table: the tail.

Despite our country’s obsession with fattening, dissecting, and searing turkeys, we almost inevitably pass up the fat-infused rear portion. According to Michael Carolan, professor of sociology and associate dean for research at the College for Liberal Arts at Colorado State University, that may have something to do with how Americans have traditionally perceived turkeys. Consumption was rare prior to World War II. When the birds were readily available, there was no demand for the tail because it had never been offered in the first place.

"Tails did and do not fit into what has become our culinary fascination with white meat," Carolan tells Mental Floss. "But also from a marketing [and] processor standpoint, if the consumer was just going to throw the tail away, or will not miss it if it was omitted, [suppliers] saw an opportunity to make additional money."

Indeed, the fact that Americans didn't have a taste for tail didn't prevent the poultry industry from moving on. Tails were being routed to Pacific Island consumers in the 1950s. Rich in protein and fat—a turkey tail is really a gland that produces oil used for grooming—suppliers were able to make use of the unwanted portion. And once consumers were exposed to it, they couldn't get enough.

“By 2007,” according to Carolan, “the average Samoan was consuming more than 44 pounds of turkey tails every year.” Perhaps not coincidentally, Samoans also have alarmingly high obesity rates of 75 percent. In an effort to stave off contributing factors, importing tails to the Islands was banned from 2007 until 2013, when it was argued that doing so violated World Trade Organization rules.

With tradition going hand-in-hand with commerce, poultry suppliers don’t really have a reason to try and change domestic consumer appetites for the tails. In preparing his research into the missing treat, Carolan says he had to search high and low before finally finding a source of tails at a Whole Foods that was about to discard them. "[You] can't expect the food to be accepted if people can't even find the piece!"

Unless the meat industry mounts a major campaign to shift American tastes, Thanksgiving will once again be filled with turkeys missing one of their juicier body parts.

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Big Questions
Why Do We Dive With Sharks But Not Crocodiles?
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Why do we dive with sharks but not crocodiles?

Eli Rosenberg:

The issue is the assumption that sharks' instincts are stronger and more basic.

There are a couple of reasons swimming with sharks is safer:

1. Most sharks do not like the way people taste. They expect their prey to taste a certain way, like fish/seal, and we do not taste like that. Sharks also do not like the sensation of eating people. Bigger sharks like great whites enjoy prey with a high fat-bone ratio like seals. Smaller sharks enjoy eating fish, which they can gobble in one bite. So, while they might bite us, they pretty quickly decide “That’s not for me” and swim away. There is only one shark that doesn’t really care about humans tasting icky: that shark is our good friend the tiger shark. He is one of the most dangerous species because of his nondiscriminatory taste (he’s called the garbage can of the sea)!

2. Sharks are not animals that enjoy a fight. Our big friend the great white enjoys ambushing seals. This sneak attack is why it sometimes mistakes people for seals or sea turtles. Sharks do not need to fight for food. The vast majority of sharks species are not territorial (some are, like the blacktip and bull). The ones that are territorial tend to be the more aggressive species that are more dangerous to dive with.

3. Sharks attacked about 81 people in 2016, according to the University of Florida. Only four were fatal. Most were surfers.

4. Meanwhile, this is the saltwater crocodile. The saltwater crocodile is not a big, fishy friend, like the shark. He is an opportunistic, aggressive, giant beast.

5. Crocodiles attack hundreds to thousands of people every single year. Depending on the species, one-third to one-half are fatal. You have a better chance of survival if you played Russian roulette.

6. The Death Roll. When a crocodile wants to kill something big, the crocodile grabs it and rolls. This drowns and disorients the victim (you). Here is a PG video of the death roll. (There is also a video on YouTube in which a man stuck his arm into an alligator’s mouth and he death rolled. You don’t want to see what happened.)

7. Remember how the shark doesn’t want to eat you or fight you? This primordial beast will eat you and enjoy it. There is a crocodile dubbed Gustave, who has allegedly killed around 300 people. (I personally believe 300 is a hyped number and the true number might be around 100, but yikes, that’s a lot). Gustave has reportedly killed people for funsies. He’s killed them and gone back to his business. So maybe they won’t even eat you.

8. Sharks are mostly predictable. Crocodiles are completely unpredictable.

9. Are you in the water or by the edge of the water? You are fair game to a crocodile.

10. Crocodiles have been known to hang out together. The friend group that murders together eats together. Basks of crocodiles have even murdered hippopotamuses, the murder river horse. Do you think you don't look like an appetizer?

11. Wow, look at this. This blacktip swims among the beautiful coral, surrounded by crystal clear waters and staggering biodiversity. I want to swim there!

Oh wow, such mud. I can’t say I feel the urge to take a dip. (Thanks to all who pointed this out!)

12. This is not swimming with the crocodiles. More like a 3D aquarium.

This post originally appeared on Quora. Click here to view.


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