Caramel Apples Linked to Deadly Listeria Infection

Halloween is nearly upon us, and that means parties, parades, pillowcases, and paranoia about people trying to poison our children. The annual media-fueled rumors of poisoned candy and razor blade–studded apples are unfounded, but there is one treat you might want to treat with extra caution: caramel apples.

From November 2014 to February 2015, at least 35 people from 12 states were infected with listeriosis. Of those people, 90 percent said they’d eaten prepackaged caramel apples before they got sick. A new study explains how it happened.

Listeriosis is an infection is caused by the bacterium Listeria monocytogenes. It mostly affects the elderly, pregnant women, and people with compromised immune systems, but in rare cases people without these risk factors can become infected. Early symptoms of listeriosis include fever, muscle aches, and diarrhea, but the infection often spreads from the gut into the rest of the body.

Once it becomes invasive, listeriosis can be deadly. All but one of the 35 people infected in last winter’s outbreak were hospitalized, and seven died, at least three of them as a direct result of the infection. Alarmed by the news, three brands of prepackaged caramel apples and one apple producer issued recalls.

But no one knew how the bacteria got into the apples in the first place. Under normal circumstances, caramel is too sludgy, and apples too acidic, for bacteria to grow. In a journal article published this week in mBio, researchers from the University of Wisconsin-Madison's Food Research Institute report two conditions that made the outbreak possible.

Bacteria that lands on the outside of an apple has usually reached a dead end. But inserting a stick into the apple breaks the skin and creates a tiny puddle of juice on the surface of the fruit. Smothering that sugary puddle in a layer of caramel then creates the perfect environment for bacterial growth.

The researchers also found that temperature plays a big role. They made caramel apples with and without sticks and swabbed them all with Listeria bacteria. Half of the apples went into the fridge and half were left on the counter. After three days at room temperature, the bacterial colonies on apples with sticks had multiplied by one thousand. Refrigerated apples with sticks were able to fend off bacteria for a week before succumbing. No bacteria at all grew on the chilled apples without sticks.

The solution here is pretty clear, say the researchers. You don’t have to give up on caramel apples. Buy them fresh, keep them in the fridge, and eat them within a few days. 

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John G. Mabanglo/Getty Images
The iMac Was Almost Called the MacMan
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John G. Mabanglo/Getty Images

After breaking out with its Macintosh line of personal computers in the 1980s, Apple was in a slump. Sales had flagged as Microsoft's Windows operating system made waves. In 1998, the company was set to unveil a product that it hoped would reinvigorate its brand.

And they almost blew it.

According to Ken Segall, the advertising genius behind their "Think Different" campaign, Apple founder Steve Jobs was expecting the iMac to reverse the company's ailing fortunes. Where older Macs had been boxy, beige, and bland, the iMac came in an assortment of colors and had a transparent chassis that showed off its circuitry. The problem, as Segall writes in his new book, Insanely Simple, was that Jobs didn't want to call it the iMac. He wanted to call it the MacMan.

"While that frightening name is banging around in your head, I'd like you to think for a moment about the art of product naming," Segall writes. "Because of all the things in this world that cry out for simplicity, product naming probably contains the most glaring examples of right and wrong. From some companies, you see names like 'iPhone.' From others you see names like ‘Casio G'zOne Commando' or the ‘Sony DVP SR200P/B' DVD player."

According to Segall, Jobs liked the fact that MacMan was slightly reminiscent of Sony's Walkman branding concept for its line of cassette players. (Later, Sony had a Discman, Pressman, and Talkman.) But Segall, who named products for a living, feared the name would take away from Apple's identity as being original. It was also gender-biased, and alienating an entire demographic of consumers was never a good thing.

Instead, Segall suggested "iMac," with the "i" for internet, because the unit was designed to connect easily to the web. Jobs "hated" the idea, along with other suggestions, even though Segall felt the iMac could provide a foundation to name other devices, just as Sony's Walkman had. Segall kept suggesting it, and Jobs eventually had it printed on a prototype model to see how it would look. After encouragement from his staff, he dropped MacMan. With this key contribution, Segall made sure no one would be lining up to buy a PhoneMan 10 years later. 

[h/t FastCoDesign]

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Big Questions
What Are Those Tiny Spots on Apples?
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The little pinprick spots on apples, pears, and potatoes are called lenticels (LEN-tih-sells), and they’re very important.

Plants need a constant stream of fresh air, just like people, and that “fresh air” means carbon dioxide. Flowers, trees, and fruit all take in carbon dioxide and give off oxygen. But unlike people, plants don’t have nostrils.

That's where a plant's lenticels come in. Each little speck is an opening in the fruit or tuber’s skin or the tree’s bark. Carbon dioxide goes in, and oxygen comes out. Through these minuscule snorkels, a plant is able to “breathe.”

Like any opening, lenticels are vulnerable to infection and sickness. In an apple disease called lenticel breakdown, a nutrient deficiency causes the apples’ spots to darken and turn into brown pits. This doesn’t hurt the inside of the fruit, but it does make the apple look pretty unattractive. In the equally appealing “lenticel blotch pit,” the skin around the apple’s lenticels gets patchy and dark, like a weird rash. 

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