9 Molds Trying to Take Over Your Kitchen

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iStock

At some point in your life, you’ve likely rummaged around the kitchen for a tasty snack, opened it up, and discovered that your treat has been cheerfully consumed by a colorful fuzz. Although your reaction was probably simple—“Ick, mold!”—not all molds are made alike. There are actually a couple thousand of genera of mold within the kingdom Fungi, and many more species, each with its own special traits and talents. Specialists, generalists, molds that like it damp, or dry, or fruity—they’re living and breeding among us.

The fuzz you see is actually just the fruiting body of any given mold—namely, its spores. These hang out trying to catch a breeze on to something organic to grow on. Under the hairy bit is the body of the mold, the mycelium. If you were to cut open a moldy bagel instead of chucking it, you’d find that the mycelium’s feathery strands, called hyphae, had already feasted on the inside, excreting digestive enzymes to turn it into a smelly web.

Just what do these molds want with us and our edibles? “To reproduce and take over the world,” says Kathie Hodge, an associate professor of mycology at Cornell University. Hodge's research focuses on the classification of fungi—including molds. She also edits the Cornell Mushroom Blog.

Hodge says the ecological function of molds is to act as recyclers. But that definition “gives them short shrift," she adds. "Molds live their own vibrant and interesting lives.” Sometimes their drama plays out in your kitchen.

Here’s a tour of some of what Hodge calls the “small and elegant” entities waiting to turn your fridge into a fascinating fungus zoo:

1. RHIZOPUS STOLONIFER, A.K.A. BLACK BREAD MOLD

It’s likely that this white-then-black species is the one that took over your bagel. How? Hodge says spores may have landed on it back at the bakery, or maybe they first infiltrated some breadcrumbs that fell unnoticed behind your toaster. Rhizopus stolonifer is a bread specialist, getting to it early, eating it like crazy, and growing incredibly fast. Molds love sugar, “and as anyone on a low-carb diet knows, bread is starch, which is basically sugar and easy to break down,” says Hodge. Is it safe to eat a Rhizopus-infected bagel? “It would taste disgusting, so don’t go there."

2. PENICILLIUM CHRYSOGENUM

Moldy Bread
iStock

It’s also possible that this puffy bluish mold is your bread-eating culprit. Yes, Penicillium is the same genus that brings you lifesaving penicillin. But don’t try to use your blue bagel as a home remedy. “I can’t tell you how many times people have said, ‘I have a cut on my arm, should I put moldy bread on it?’” sighs Hodge. Mold only morphs into antibiotics after it’s been extracted from its growth medium and purified in a lab and furthermore, the Pencillium group as a whole—there are over 300 species—is famous for making many and diverse toxins. Still, one species also makes blue cheese (Penicillium roqueforti), and another cures salami (Penicillium nalgiovense).

3. WALLEMIA SEBI

This is one of the true oddballs of the mold world—an extremophile that likes to live, as this name suggests, in extreme outposts. Extreme for a mold is a place that’s salty or super-sugary, and therefore, dehydrating. Enter Wallemia sebi, thick brownish blobs of which Hodge once found floating in her maple syrup. “It’s really slow and patient,” she says, hiding out and waiting for its time to pounce. “So, if you eat your maple syrup at a normal rate, you’re never going to see it.” Wallemia sebi is the source of some amount of controversy among Hodge’s colleagues. Some of them insist that it’s harmless. But remember, Hodge points out, “it’s been eating and excreting into your syrup. I highly recommend that people throw it out.”

4. ZYGOPHIALA JAMAICENSIS, A.K.A. FLYSPECK

flyspeck mold on green grapes
Patrick Hertzog/AFP/Getty Images

This mold is commonly found growing on apples (and grapes), and is also known as flyspeck. Confusingly, flyspeck can be caused by a variety of mold species, varying by region and type of apple. Flyspecked apples are usually snubbed by consumers, despite the fact that their little black bumps are harmless and grow only on the skin. “It’s a hard life, being a plant,” says Hodge. “Every one I can think of has multiple fungal problems.” If you find flyspeck on your fruit at home, console yourself in the knowledge that it came in from the orchard and likely isn’t lurking in your cupboards.

5. FUSARIUM VERTICILLIODES, A.K.A. MAIZE EAR ROT

Ever peeled open an ear of corn and found a patch of pink sliming the kernels? That’s Fusarium verticilliodes, part of a huge genus that produces some truly terrible mycotoxins. It loooooves both the sweet corn you buy at the market and the field corn that’s manufactured into corn chips and fake-meat patties. And it can survive processing to cause things like estrogenic effects and immune suppression. Hence, Fusarium is highly regulated to try to keep it out of our food supply. And oh yeah, some species have also been used to make biological warfare agents.

6. BOTRYTIS CINEREA, A.K.A. NOBLE ROT FUNGUS

mold on strawberries
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Fluffy grey Botrytis cinerea will gladly sink its spores into the strawberries in your fruit bowl. It’s not particularly toxic, says Hodge, but it can gobble up fruit with lightening speed. It comes in with your berries from the field, where damp conditions make it hard to eradicate. The upside: This mold species is also known as “noble rot.” When it turns up (uninvited) on grapes in vineyards, it dries them out and concentrates their flavor; the grapes can then be used to make sweet wines like Sauternes (from France) and Tokaji Aszú (from Hungary and Slovakia).

7. ASPERGILLUS NIGER, A.K.A. BLACK MOLD

“This one is interesting,” says Hodge. “It can grow on onions—it shows up as black flecks between the layers. And it can also cause ear infections in humans.” But its talents don’t end there; Aspergillus niger also causes you to exclaim, “Ooh, lemons,” when you drink certain manufactured “lemony” beverages. (“No,” corrects Hodge. “It’s mold.”) Niger’s sister, Aspergillus oryzae, is used to make miso and soy sauce. And another, the parrot-green Aspergillus flavus, which favors peanuts and tree nuts, “is the worst fungus I can think of,” says Hodge. Its crimes against humanity include causing liver cancer.

8. DIPLODIA NATALENSIS

rotten lemon put on wooden table
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Most of us have reached into the vegetable drawer and pulled out a green lemon (thanks for nothing, Penicillium digitatum). But Diplodia natalenis is responsible for an unattractive darkening—and sometimes, mush-ening—of a lemon’s stem end. This mold is also devious; it lives inside the dead wood of trees back at the grove and doesn’t actually show itself until the fruit’s already been picked, packed, and stored in your refrigerator.

9. MUCOR CIRCINELLOIDES

This little guy (gal? Other? Molds can produce spores asexually and often sexually, too) is something of a generalist. It likes fruit, vegetables, and dairy. To wit: a virulent subspecies of Mucor circinelloides was implicated in a nausea- and vomit-inducing episode that affected more than 200 people who’d eaten some moldy yogurt back in 2013. How virulent? Tests showed that it could survive passage through the digestive tract of lab mice. But how it got into the yogurt in the first place remains a mystery.

How Coronavirus and 31 Other Infectious Diseases and Viruses Got Their Names

Rotavirus—from the Latin rota, for "wheel"—is named for the wheel-like appearance of its particles.
Rotavirus—from the Latin rota, for "wheel"—is named for the wheel-like appearance of its particles.
Dr_Microbe/iStock via Getty Images

As you may already know, the corona in coronavirus has no relation to a certain refreshing beer often served with a slice of lime. Corōna means “crown” in Latin—and Spanish and Italian, too—and virologists chose it in 1968 to describe the group of viruses characterized by crown-like spikes that protrude from their surfaces.

So how do other viruses and diseases get their names? Based on the infographic below, created by Adam Aleksic for his website, The Etymology Nerd, there isn’t just one way. Some, like the coronavirus, are named for how they look under a microscope. The rota in rotavirus, for example, which means “wheel” in Latin, reflects the virus’s wheel-like appearance when viewed beneath an electron microscope.

Others are named after the locations where they were discovered or studied. In 1947, scientists named a newly identified mosquito-borne virus after Uganda’s Zika Forest. In 1977, Yale researchers investigating a string of pediatric arthritis cases in the town of Lyme, Connecticut, started referring to the illness as “Lyme arthritis.” Later, the name was modified to “Lyme disease” when scientists realized patients were exhibiting other symptoms, too.

Still others are characterized by the symptoms they cause. People with tetanus—from the Greek tetanos, for “tension”—usually experience muscle stiffness, and the skin of yellow fever sufferers often takes on a yellow tint due to jaundice.

Find out the origins of malaria, measles, and more below. And follow The Etymology Nerd on Instagram for more fascinating etymological explanations.

etymology nerd infectious disease names infographic
Unsurprisingly, there's a lot of Latin in this infographic.

These 8 MasterClass Courses Will Get You Out of Your Netflix Funk

Chef Gordon Ramsay is just one of the professionals lending their knowledge to a MasterClass course.
Chef Gordon Ramsay is just one of the professionals lending their knowledge to a MasterClass course.
Franco Origlia/Getty Images

Although binge-watching Netflix is always a great way to kill a few hours, you might want to shake it up and do something a little more substantial with your free time. That’s where MasterClass comes in. A subscription package that features over 80 virtual courses in a wide range of subjects, MasterClass can help you explore exciting new subjects or improve your knowledge in an area you’re already familiar with. And all the classes are taught by highly recognizable experts in their fields, so you can be confident that the lessons you’re learning are solid (that Martin Scorsese probably knows a thing or two about filmmaking, after all).

The courses themselves are broken up into individual lessons that are only around 10 minutes long, so fitting them into your schedule is as easy as becoming a professional chess player (or it will be, once you’ve finished the course). MasterClass is priced at $15 a month for unlimited classes or at $90 per course, and you can sign up here.

So whether you want to become the next great young adult novelist or an expert bartender, MasterClass has something for everyone. Check out a few highlights from the course list.

1. Cooking with Gordon Ramsay

Gordon Ramsay, known for his sharp demeanor and high expectations in the kitchen, is an international chef, restaurateur, and television host who’s nothing short of legendary. And in his MasterClass series, he’ll teach you to become a legend, too. This series features the softer side of Ramsay, who teaches you knife techniques, seasoning tricks, kitchen layout, and much more. And, for anyone ready to level up, he also offers Cooking II: Restaurant Recipes in the Kitchen.

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If you’re ready to become an award-winning bartender—or just make a decent martini at home—look no further than this 17-lesson course with master mixologists Lynnette Marrero and Ryan Chetiyawardana. You’ll not only learn to craft the perfect cocktail, but also how to safely incorporate raw eggs into drinks, make complementary drink “seasonings,” and discover the best liquor to pair with food (who knew that whiskey and blue cheese were a match made in heaven?). A good drink has the power to bring people together, and after this course, you’ll be the go-to guru for any dinner party.

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After you’re through with R.L. Stine’s class on writing for young adults, you may just become the next sultan of the Scholastic Book Fair. According to his website, Stine has written over 330 books over the course of his career, and he’s provided thrills and chills to millions of readers with his beloved Goosebumps and Fear Street series. Now, he’ll teach you some of his favorite tricks of the trade, like why you should always start with the ending (so you can focus on fooling your reader for the entire book) and how writing from personal experience makes for a more sincere scare. This masterclass will help you perfect the art of scary storytelling and overcome any fears you might have about putting your own experiences on the page.

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4. Conservation with Dr. Jane Goodall

Dr. Jane Goodall is best known for her groundbreaking work with chimpanzees and gorillas, but she’s more than just a scientist—she’s an environmental activist and conservationist who wants to ensure that animal habitats are preserved for years to come. In this course, Dr. Goodall will share some of the conservation lessons she’s learned as a scientist, identify the central problems facing our planet today, and share effective methods for creating change. As she says, one of the best ways to confront environmental issues is by “telling stories, meeting with people, listening to them, and then finding a way to reach the heart.” This course will show you how.

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Garry Kasparov, a chess grandmaster and world chess champion, will help you dust off your old chessboard and learn to play the game like it’s an art form. This 29-lesson class starts with the basics and gets more complex the further you get into the course. Using the tactics he’s curated throughout his career, Kasparov will show you how to approach chess with a strategist's mindset, including the basics of openings, interference plans, and endgames. This class even features other “students” so you’re not just studying the techniques, but seeing how they play out in real time, too.

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