We’ve all chewed Juicy Fruit gum at some point, enjoying the sweetness for about 20 seconds before it completely dissipates and turns into a rubbery wad devoid of all flavor.

But what exactly is that distinctively delicious flavor that briefly tickles our taste buds? Wrigley has kept the secret ingredient under wraps for decades; a wrapper from 1946 describes the unique taste as “a fascinating artificial flavor.”

One fan allegedly emailed the company in 2002 and got this response:

“I'm afraid we can't be very specific because, for competitive reasons, we consider our Juicy Fruit flavoring formula to be a trade secret. I can, however, tell you that the mixture of fruit flavors in Juicy Fruit is comprised of predominately lemon, orange, pineapple, and banana notes.”

Despite the company’s response, some people think the gum tastes less like common citrus and banana, and more like an exotic fruit called jackfruit; it even has a similar aroma. However, this probably isn’t the case because, as Today I Found Out points out, there don’t seem to be any records of Wrigley ever importing the fruit or its juice.

Instead of actual fruit or even fruit extracts, some chemists believe that the gum smells like jackfruit because they both contain a chemical called isoamyl acetate. Isoamyl acetate, sometimes referred to as banana oil or essence of pear, is a common ingredient in bubble gum, and some fruits produce it naturally as they ripen.

When Juicy Fruit first appeared on store shelves back in 1893, isoamyl acetate was most commonly produced by whiskey distilleries as a byproduct—and at the time, Illinois, also home to Wrigley, produced more than 18 million gallons of the hard stuff every year. Smells Like Science speculates that Wrigley purchased isoamyl acetate from local distilleries until a synthetic process became available some years later.

Much like the Colonel's 11 secret herbs and spices, or Coke's "7x" flavoring, we may never know what, exactly, is in Juicy Fruit gum. But there is one thing we do know: it's delicious—for 20 seconds.

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