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My husband and I have battled continuously for years about whether scraping the mold off the top of — well, anything — makes it OK to eat, or if once a spot of green invades the top of a barely used jar of jam we’ve got to call it a loss and toss it out. I’m always willing to scrape off the top, cut off the moldy crusts, etc., and carry on with the meal. My husband, not so much.

Well, turns out the USDA has weighed in on the argument with interesting findings. My favorite part of the Safe Food Handling fact sheets is this chart on how to handle moldy foods (very, very carefully is not one of the answers):

howtohandlemoldyfoods.png

An article on CNN takes it one step farther, suggesting that you shouldn’t eat the pizza you left out on the counter overnight (What? Even my husband finds this to be absurd). And I never would have thought about eating moldy sausage, hard or not.

In the end, experts and the USDA report both recommend throwing out most moldy foods. I admit, the idea of threads of mold weaving their way into the bottom of the container gives me a moment of pause; but if you read about what happens if you eat a slightly tainted dollop of sour cream, the most likely effect will be a stomach ache.

moldy_yogurt_ick.jpg
BlueCheese By jkuma.jpg

Sad mold and happy mold. (Photos by napalm nikki and jkuma, respectively)

I’ve had stomach aches from eating myriad meals over the years, made by friends, family, and fast food joints, so this news isn’t likely to change my habits. After all, we all know about the happy molds found in blue cheeses and on the outside of Bries and Camemberts. Now there’s some mold I can sink my teeth into.

Anyone out there have any experience working with molds in cheese-making, or have a gruesome tale that will cure me from my “just scrape it off” attitude? Tell me about in the Comments.

shawnconna

Sometimes helpful editor and digital media director at MAKE and CRAFT.


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Comments

  1. Bob D says:

    Well, it depends on the mold. Unless you’re an expert in the field with an electron microscope to study the structure of what’s growing, you can’t be sure. Food is cheap and readily available in the USA. Health care is quite a bit more expensive, so just throw it out if in doubt. Some mold such as the very common Aspergillus can cause severe health problems and death.

  2. Mister Fright says:

    I’m allergic to penicillin and if I take it I could suffer from anaphylaxis, which one of the things that could happen is constriction of my airways and then maybe my death.

    Well, one day I ate some moldy bread. “What’s the worse that could happen?” Later that day I was covered in hives, another thing that could happen if I have penicillin. So I thought, since penicillin comes from a fungus (I think), maybe there was a form of fungus in the mold that has something similar to penicillin.

    I know that’s a stretch of logic, but since then I don’t touch anything remotely moldy.

    1. John says:

      Mold is fungus. Penicillin is so named because it was originally isolated from the mold Penicillium, which can be found growing on food. If you are allergic to penicillin, you should definitely avoid moldy food.

    2. technos says:

      All penicillin we know today derives it’s heritage from a spore that landed on a petri dish from the air and formed a mold – the same kind that can land on bread easily to form mold;
      http://en.wikipedia.org/wiki/Penicillium_notatum#Science_and_History

  3. Stephanie says:

    though there’s always a first time..

    I don’t eat any foods that have slimy sorts of molds, as they can’t be isolated, but I have no issue with isolating bread molds and cheese molds. And I’m quite used to just cutting off the bad parts of most vegetables and fruits. Any leftovers with eggs, milk or meat, toss if they get slimy. or smell bad.

    My mom is a big proponent of just scraping off the bad parts and serving the rest, so I suspect I have a strong stomach.

  4. deanes says:

    I am a fan of old coffee. Actually prefer it a day or two old. I have actually spooned off the mold, and zapped it in the microwave, instead of throwing it away.
    Unless you are allergic, I don’t think ingesting molds will hurt you. I expect its better to eat them than breath the spores. Most all fruits and vegetables have some mold right out of the field. Expect anything labeled “organic” to have lots more mold.

  5. Noadi says:

    I don’t fret much about mold, though the only food I regularly scrape mold off of is cheese or cut the moldy part off a loaf of bread. Mmmm… there’s some good mold in cheese, particularly fond of the blue cheeses.

    My brother on the other hand has a severe allergic reaction to penicillin. He once ate some bread not realizing the little bit of powdery stuff on it was mold not flour and nearly went into anaphylaxis, spent a few days in the hospital, and 2 weeks off duty (he’s in the military) since he was covered head to foot in hives. Don’t mess with mold if you have that sort of allergy, treat it like it’s penicillin.

  6. Jack of Most Trades says:

    ‘Mildew is good for you. It’s the next best thing to fresh lettuce. Be thankful for what grows down here.”

    1. Love the Das Boot reference, Jack!

  7. Big Dave says:

    I used to like all cheeses (I lived in the UK for a bit and got to try some really gouda cheeses :)

    Working at an outback steakhouse changed that for me. I was a prep cook (10 years ago) and one of my jobs was making 5 gallons of salad dressing at a time. 5 gallons of blue cheese used half a wheel, so we’d wrap up the unused half and put it back in the fridge.

    I remember being fastenated by the wheels because they were just solid white cheese, but on one side it looked as if a grid of needles had been stabbed into the wheel. When you sliced it open you’d get a cross section and you could see that the manufacturer had apparently innoculated the cheese with mold through those injection needles, and the blue mold was spreading from those holes.

    One day I opened it up, and was like “damn, this is more blue than cheese…boss, you wanna take a look at this and tell me if it’s kosher?”

    He was like, “ehhh, it’s pretty fucking moldy, but it’s supposed to be. Use it.”

    I dont think anybody got hurt from eating that stuff, but i wont touch it, and go so far to order buffalo wings with ranch instead of blue cheese. not gonna do it.

    //allergic to Penecillin too

  8. Spooge says:

    only thing I’ll eat after getting moldy is hard cheeses, like cheddar. Just cut off the mold and you’re good to go.
    Anything else though, ferget it. Although I”m sure I’ve accidentally eaten weird stuff in the dark & not realized it until much later… if ya know what I mean.

  9. Mike says:

    The reason that the USDA guide above makes the distinction between moist and dry foods is that bacteria need more moisture to grow than moulds. It’s not really the mould that’s going to give you an upset stomach or cause any damage (penicillin allergies aside) other than that unpleasant earthy taste. With moist foods the fact that the mould is there means that there is almost certainly a whole zoo of different bacteria there too, it’s just that mould is easier to spot. Food-poisoning tends to be bacterial in nature.

    Moulds can grow in much drier environments (like that cured sausage mentioned, or on bread) and so a bit of mould on these can be brushed off, safe in the knowledge it’s unlikely that there are also food-poisoning bacteria there. With a piece of chicken that’s mouldy, you’re risking bacterially casued Salmonellosis and worse. A dry sausage that’s got wet and gone mouldy (presumably because you’re keeping it in the garage or something?!) you should throw out.

  10. Katherine says:

    Most anything that gets moldy, I will throw away. But my mom has always cut moldy spots off of cheese, so that’s what I do, on the very rare occasion that I have cheese, and that I have it long enough for it to get moldy. I also have always cut the moldy spots off of bagels and toasted them and eaten them. I figured it would work the same way as cheese. I found out a couple years ago that it doesn’t work that way, but I still do it some times. Only with bagels, no other bread, I am not sure why, but I trust my bagels more. Also, doing this has never made me sick, so I don’t worry about it. But I won’t deal with anything else moldy at all, I trash it, and if it is moldy enough I will trash the whole container if the container is plastic, even tupperware type stuff.

    Also, the pizza thing is just silly. I am not going to worry about pizza left out over night, as long as it was stolen by the pets over night ^__^

  11. bob_d says:

    Molds growing in soft, wet mediums will contaminate the substance with mycotoxins. Some mycotoxins are carcinogens (in fact, the most potent carcinogen known is produced by a common mold)… so you *might* just get a stomach ache in the short term (some mycotoxins can kill you outright), but the long term effects could be a bit nastier.

    1. Mitch says:

      I have the same concern about mycotoxins, plus I’m allergic to mold. The part of the mold that you see is its reproductive structure, and there’s more of it growing in
      microscopic threads below the surface, so I cut pretty widely around the mold if I want to save food with mold on it.

  12. Mako says:

    What about bread? I started bringing lunches to work last year and more than once have picked little dots of mold off the roll used for the sandwich. Of course the roll was a just a tad stale but generously slathered with dressing the sandwich actually tastes pretty good.

    1. Anonymous says:

      Hard cheese I’m generally pretty ok with – I’ll just cut off the offending pelt. But I have a couple of reasons for throwing away mouldy bread.

      Firstly, the thread-like mycorrhizae can grow much faster and further through the porous open matrix provided by bread than through hard cheese. So by the time the fuzz appears on the surface, the mould probably has a really good hold on the rest of the loaf.

      And secondly, some grains (and by extension, some breads) can become infected with a certain type of mould called Ergot (Claviceps spp.. Ingesting ergot can have very unpleasant side effects (Some of which I voluntarily experienced in my dark, irresponsible past – never again!)

      Now, I don’t think ergotism is that common these days, but for me, fuzzy bread is to be thrown away. If the rats and seagulls down at the tip end up tripping out on ergot, that’s their problem. I’ll not let it be mine thank you very much.

  13. Jennifer Elaan says:

    I’ve had a Brie infect my cheese drawer a couple times. The signature white rind mold started appearing on a few nearby cheeses.

    I saw no signs of any other cultures, so I assumed it was safe enough to eat.

  14. Western Infidels says:

    My wife was once hospitalized with food poisoning from eating pizza that had been left out overnight.

    We put our leftover pizza in the fridge now.

    1. Sunny says:

      Blue cheese looks like it’s been inoculated with a grid of needles because that’s EXACTLY how it’s produced.

      If the mold on a blue cheese is blue, then it’s supposed to be there — don’t worry about it.

      Green molds can be cut off.

      Slimy or shiny pink or orange molds are the bad guys — just chuck whatever it’s growing on, as that’s the stuff that will make you sick.

      The white mold on Brie (called a ‘bloom’) is most definitely alive. I live in the Brie region of France, so usually have Brie in my fridge. When you cut a slice off and put the rest back in the fridge, the bloom will actually regenerate and grow over the cut surface. It’s absolutely harmless…eat it if you like, trim it off if you prefer.

      1. cheesehead says:

        The blue mold cultures (penicillin roqueforti) are pitched into the milk during the cheesemaking process. Curds and whey are separated, the curds are placed into forms (a different kind of mold, heh) and if necessary, those newly formed cheeses are pierced with copper or steel needles to create spaces for air to invade the cheese. As the cheese ages, those mold cultures multiply and spread to nearly every available crevice in the cheese. Amount of blueing depends partly on how long the cheese is allowed to age. Interesting fact: when a wheel of blue cheese is initially cut, the interior mold often shows as a mustardy yellow or light green/blue color. Within minutes of exposure to the air in the room, it will deepen to the dark blue/dark green color we associate with blue cheese.

        Orange and yellow molds on cheese are NOT dangerous, and actually pink/orange growths are usually yeasts, not molds. And, the lemon yellow patches that show on the outside of a St. Nectaire are actually indicators that the cheese is at its peak and should be eaten. And be careful not to confuse the orange smear of a washed rind cheese with a colony of mold–that smear is Brevibacterium linens, a harmless but stinky colony that is actually encouraged by makers of certain cheeses. Yes, it is the same bacteria you find on the surface of your skin, and that’s why those cheeses smell like gym socks.

        The molds (as far as cheese goes) I recommend to stay away from are the black and dark brown ones, but even then, only when they are somewhere they are not supposed to be. For example: on my block of mozzarella…toss it. Amongst the myriad of other colored molds/yeasts on the outside of the cheesecloth rind of my farmhouse cheddar…I keep it.

        Moldy bread, I toss, because now matter how I want to, I cannot *not* smell/taste the mold.

        One of the more surprising things that can get you sick is improperly stored cooked rice. Did you know that more cases of food poisoning from sushi actually originate from the rice than the raw fish? Bacillus cereus is…serious.

  15. Jon-o says:

    From what I heard in an interview with a cheesemaker, the holes in the outside of blue cheese aren’t actually for ‘injecting’ mold, but just to let air in so that the naturally-occurring mold can grow better. I wouldn’t be surprised if some (cheaper?) blue cheese did have it actually injected somehow.

  16. Eva says:

    Some years ago I used to take care of an old lady in the summer months. I used to prepare meals for her. She is a very well educated biologist only stubborn as a 89 years old can be. Once we found mold on the cheese. As a rule I cut the mold from the cheese, specially in that case because the mold was stemming out weird things. She complained that it was a waste and that the mold is not bad for you. Then when I turned around for a second – zac – she ate the moldy piece…
    There were no consequences though.

  17. Michael says:

    I don’t much care for the stuff, even on cheese where it belongs, but my aunt, who was an artist and basically hired out the raising of her kids (just so you know her homemaker points) invited us over for lunch once, and when making the salad pulled out a piece of green furry cheddar (and I mean it had a RUG of mold on it, all around) and happily grated it all into the salad. I asked her about it, and she just muttered something about penicillan, and that was it.

    We ate the salad. We did not die. I don’t do this at home.

  18. Geis says:

    My grandfather had the habit of allowing bread to actually go moldy. He would put it in the toaster and then scrape the toasted mold into a container. Later, he would put some peanut butter on some un-moldy bread and then sprinkle some of the toasted bread mold onto the sandwich.

    His logic was that penicillin comes from bread mold so. . .

    When I was back in junior high school and he provided me with one of these containers to get me to join him in his healthy living ideas, I did not take him at his word. I got some agar solution, cultured the bread mold and borrowed an expansive tome of molds, fungi and slimes from the library system. Utilizing a stereoscopic microscope borrowed from the high school I investigated and confirmed my suspicion that this was not the penicillin bread mold and, while it probably wouldn’t do any harm, it was unlikely to do any anti-biotic good.

    Years later when I was going to college, I moved in with my grandfather. He no longer saved the bread mold but his years of doing so had allowed mold to permeate the house. We could not keep bread in the house. Double-wrap it. Put it in a breadbox. In the refrigerator. No matter what we did, a loaf of bread would not survive a week. Other foods would also go moldy very quickly. The only way were were ever able to improve the situation was to replace all the carpeting in the house.

  19. Anonymous says:

    If the food item was all that good in the first place it would have been consumed prior to going moldy. The molds that occur incidentally are never the right molds, and do not improve the food product. It’s a false economy to go ahead and just eat the tainted food because even if only 1 in a hundred make you quite sick, I’m pretty sure you would have paid much more than what you have saved to avoid having been made ill.

  20. marcbl says:

    Mold is merely an indicator that your eyes were bigger than your stomach (you bought more than you could eat); I’ve never had any mold problems with foods ≤ 1 week old.
    I blame Costco and the Cold War era “stockpiling” mentality more than anything.

  21. Cyril says:

    Hello,

    Here in France, we have a lot of cheese whith moisture into.
    We call this family of cheeses : “Pâte persillée” (like parsley)

    Here is a great selection of theses cheeses, the best of all is “Roquefort”: http://www.ledictionnairevisuel.com/images/qc/fromages-a-pate-persillee-270250.jpg

    Nobody have never been sick with cheese! this is the best food in the world ;-)

  22. Splint says:

    Have their been any studies done between allergies and picky eaters? I was always playing in the dirt as a kid and I’ll eat anything. I’ve eaten a slice of pizza left under the couch for who knows how long (on a bet). I’ll eat bread withOUT cutting off the mold, I like the taste, tastes a bit like dirt. Anyway, my point is my sister was a picky eater. I don’t think she ate anything other than pop-tarts for breakfast. She rarely ate fruit, veggies, etc. and would never think of eating something straight from the garden without washing it first.

    She was allergic to penicillin, strawberries, dairy and cashews. I did not have any food problems. I know this is only anecdotal though.

    1. Anonymous says:

      yes indeed, look up “hygiene hypothesis,” and you will see you have intuitively arrived at this widely accepted theory.

  23. CBD says:

    when I worked at an upscale cheese counter during college, our cheese guy broke it down this way:

    mold on something hard, like parm or very sharp cheddar (aged so much it crumbles instead of cuts) can be scrubbed off because the mold is just in that spot.

    mold on something soft, like bread or soft/semi-soft cheese, has to be completely thrown out because that mold actually sends little threads throughout the product.

    Also, the reason you should be cagey about mold on cheeses and other cured things is that cheeses are preserved by microbes that have a pretty strong defense against other microorganisms colonizing what they’re already living on. So, the molds that grow on such things are generally much stronger, and instead of eating, say, dairy, they are eating the other microbes. and they can make you sicker by eating a relatively small amount of them.

    I have no idea if any of that is true or not, but he ran a clean shop, and it made sense . . . .

  24. RD says:

    I hiked the Pacific Crest Trail in 2008 with my cousin, and one of the things we would hike in with was summer sausage cut into small rounds. Normally, the sausage wouldn’t last but two, maybe three days, and I recall how excited we were to sit down and eat something as substantial as sausage and cheese.
    At one point, we were camped at Muir Pass (12,000 ft) and to celebrate our getting up there we ate the last of the sausage and cheese. I have a faint recollection of the smell and taste being a little funny, and then I definitely recall my next 4-5 days of stumbling, stomach churning, vomiting, diarrhea, and head spinning as I dragged myself the next 70 miles to Mammoth, CA. It was one of the hardest things I’ve ever had to do.
    Sausage and hiking? Never again for this kid.

    1. Anonymous says:

      They make a sausage specifically for hiking:

      http://en.wikipedia.org/wiki/Landj%C3%A4ger

      At the place I get mine, it is sold unpackaged, off of a wooden stand beside the cash register.

  25. lolosaka says:

    I constantly fight with my wife over whether or not scraping the mold over food, but a few years ago, I learnt my lesson the hard way:
    just before leaving home to go visit Hiroshima for the holidays (I live in japan), I had the foolish urge to eat the intact part (or so I thought) of a slice of ham which was already half-green with mold.
    everything was fine early the next morning when I was woken up by intense cramps which can best be compared to the labors of childbirth.
    My wife took me to the ER as I was kicking the dashboard from the unbearable pain, and it was bad for a couple of days afterward.
    So proceed with caution, and at your own risk!

  26. jenndlv says:

    I used to work in a cheese cave and white bloom mold is friendly. Just watch out for anything that is blue, black, pink or has FUR. These colors indicate that the cheese is receiving more moisture than it should and is culturing unintended mold. If it’s just a tiny spot, just scrape it off and change the plastic wrap or cheese container. If your aged goat cheese/Loire Valley/bloomy becomes puffy or dusty, but not furry; simply pat it down with your hands.

    Cheese that has been pre-cut and wrapped in plastic has a propensity to grow more mold (more exposed surface area). Try to get whole pieces of small cheese or freshly cut cheese that is wrapped in parchment. The exception is blue veined cheeses. They should be immediately unwrapped at home and wrapped in foil to keep the butterfat from seeping. In plastic, it will sweat and grow grey mold on the outside.

  27. Roger says:

    All I can add is don’t eat a tuna and mayo sandwich left inside the car on a summer’s day. Tasted alright but boy howdy…

  28. Apis says:

    According to what I have heard from different experts (and is in agreement with the above mentioned articles) is that you should, in general, throw out any moldy food. That is because, mold is a fungus, and the part you see is really the fruiting body of the organism. Most of the mold consist of root threads, that by the time you can see the fruiting bodies, have eaten through your entire jar (eg. of jam).
    Although many molds are benign, some can be very poisonous and it is difficult even for an expert to identify the type of mold without a microscope.

    So for your own sake, it’s best to not eat any moldy stuff, even if you cut off the fuzzy parts.

    Although there are some exceptions such as hard cheese which should be safe if you cut of any mold + 1 inch, because the mold have trouble penetrating the hard solid texture.