I left a fully cooked ham in a bag out overnight. It was refrigerator temperature when I took it out at 9pm. Our Seattle home was not heated; it was about 50 degrees last night. I found it at 6am and threw it back in the fridge, in case it was still good. I would cook it again and then use it with eggs or sandwiches. Would this be ok?
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How was it protected? I.E. still sealed? I don't know if that makes a difference, but it may – mfg May 02 '11 at 20:06
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1Does this answer your question? [How do I know if food left at room temperature is still safe to eat?](https://cooking.stackexchange.com/questions/34670/how-do-i-know-if-food-left-at-room-temperature-is-still-safe-to-eat) – moscafj Jul 14 '20 at 13:43
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1@moscafj Is it really worth the effort to mark a 9-year-old question as a duplicate? – LSchoon Jul 14 '20 at 15:25
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@LSchoon effort? It seems to me that cleaning up the site is always worth it....but, alas...I am only one vote. – moscafj Jul 14 '20 at 16:00
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It's probably even safe to eat without cooking again; the refrigerator is likely only about 10 degrees colder, and that generally translates to accelerating rates of spoilage (mostly growth of pathogens) by a factor of 3-5 or so. For example. at 10C (50F), E. coli only manages to divide once every 8 hours or so (see Ratkowsky et al., "Relationship Between Temperature and Growth Rate of Bacterial Cultures", J. Bacteriology, vol 169, p. 1 (1982) for a not-very-clear example of growth curves--I've seen these curves online, but unfortunately I tried and failed to find an easily accessible one this time).
It's almost certainly safe to eat with cooking (fully, to at least ~160 at the center), which would kill anything that managed to grow on the ham. The only thing to worry about with well-cooked food is whether bacteria or fungi have managed to produce so many toxic chemicals that the food will make you ill--and in this case, it's been too cold. (At those temperatures, not only is growth slow, but most anything is slow, including production of anything toxic.)
So I'd say--cook away, enjoy, and don't worry about it.
P.S. I have in practice eaten ham left out at warmer temperatures for longer.
Edit: In response to a comment about bacterial toxin production, I want to reiterate that colder temperatures slow down metabolism of just about everything, including toxin production. This is because, at a basic physical level, reaction rates are governed by the Arrhenius equation which translates, for simple reactions, to a doubling of reaction rates for ~10C increase in temperature. Of course, organisms like bacteria have more complex interactions, but this still gives an order of magnitude estimate. Furthermore, research has been done on production of bacterial toxins. For example, Skinner & Larkin (J. Food Protection vol 61 p. 1154 (1998)) wrote a paper called "Conservative Prediction of Time to Clostridium botulinum Toxin Formation for Use with Time-Temperature Indicators To Ensure the Safety of Foods", which gives, for food innoculated with the bacteria, a time-to-detection-of-toxin of 2-3 days at 10C. In fact, they did the research because food storage at open-face refigerators in stores often allows products to get up to as high as 10C (at least as of 1998).
Similarly, in Bonventre and Kempe ("Physiology of Toxin Production by Clostridium botulinum Types A and B, III"), their 10-18C toxin line is flat for 24 hours at the baseline level before creeping up by a factor of 3 or so between 24 and 48 hours (figure 4).
These are just examples, but you find the same general trends everywhere because of the fundamental physical relationship between reaction rates and temperature.
Rex Kerr
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2This is not only bad advice, it is dangerously bad. Unless you have taken samples from the ham in question and cultured any bacteria present, you have no idea whether or not *this specific ham* is safe to eat. Please do not give advice like this. – May 02 '11 at 20:54
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10What evidence do you have, daniel, that this is bad advice? I cited research on microorganism growth to back up what I said. Leaving your ham on the table during dinner for an hour and a half allows stuff to grow up more than overnight at 50F. Shall we throw out any food that sits out during a moderately leisurely meal? – Rex Kerr May 03 '11 at 02:58
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3What evidence? Basic safe food handling procedures. Four hours in the danger zone--4 to 60 degrees Celsius--is the maximum cumulative time that any perishable food should have. This had nine hours in that temperature range. You are welcome to do with your own body as you see fit--as do I, when at home. What you should *never ever* do, especially ona site like this, is advise people to do things which may be injurious to their health. Again: dangerously bad advice. – May 03 '11 at 07:07
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@daniel makes a good point. @Rex should have noted there are some risks. For example, if the ham already had high levels of bacteria or toxins due to improper storage or cooking at the store. With that said, it's a risk many people have taken. I am not an expert and this is not advice, but at my home I would eat it and I would start with a small piece because with heat resistant toxins the dosage does matter. More will make you sicker. – Todd Chaffee May 03 '11 at 09:33
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2I can only imagine the people upvoting this answer have *absolutely no clue* about proper food handling procedures. – May 03 '11 at 09:35
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8@daniel - I don't think you understood the question. The question seemed to me to be, "I did something that violates standard food handling rules. Can I make an exception?" All you're saying is, effectively, "no no no no no!" without any evidence. If you want to keep yourself safe _legally_ this is exactly what you should do. Otherwise, you need to look at the question more deeply to understand why food spoils. If you do not understand how the risks arise, then I agree, the only safe thing to do is adhere strictly to general rules. – Rex Kerr May 03 '11 at 14:09
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2I understood the question perfectly. I understand how risks arise. I understand further that it is monumentally stupid and irresponsible to advise people to do risky, potentially life-altering things. Do you understand that? Do you understand even the basics of safe food handling? It would appear not. Again, you can do what you like with your own body. When it comes to other people in circumstances which you do not fully understand, it behooves you to *not advise them to do things which could make them exceedingly ill*. – May 03 '11 at 18:58
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5@daniel - If you have any evidence or data to share--for example, come up with _any_ scenario where the original ham could have been edible but now is not, backed up by some sort of research--then we could maybe resolve things. As such, since you are simply repeating your opinion and not giving any evidence for it, we'll have to agree to disagree. (And yes, I understand both safe food handling, sterile technique in the laboratory, bacterial growth pathways, and so on.) – Rex Kerr May 03 '11 at 19:35
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2Any scenario? Easy. OP went to the bathroom, failed to wash hands properly (which pretty much everyone does), touched the ham. Which has now been left out overnight. Look again, you can take whatever risks you want with your own body. It is grossly irresponsible to advocate others do the same when you are unaware of the circumstances. Err on the side of caution. I am *done* with you. – May 03 '11 at 20:03
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3@daniel - OP had E. coli on his or her hands and touched the ham, is what you're saying. E. coli has a doubling time of 8 hours at 10C. So after 9 hours out in the rather chilly house, there are approximately twice as many bacteria as when he or she touched it. Then, they all get cooked and die. It would have been worse to just eat the ham the previous evening, because then the bacteria would have been alive! Try another scenario? – Rex Kerr May 03 '11 at 20:57
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2No. You want to go ahead and advise people to do risky stupid things when you are not aware of the specific circumstances, go ahead. Clearly the basic ideas of food safety are completely lost on you, as is the general concept that you shouldn't counsel people to do things which can be injurious to their health. So go ahead! Eat meat that's been sitting out for 9 hours! Cut vegetables for your salad on the same cutting board as raw meat! Go *right ahead* because someone who knows *nothing* about food safety says it's okay! – May 03 '11 at 21:25
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1Or I have a better idea. You put enough money in an escrow account to cover all of the OP's potential medical bills in case s/he gets sick from eating the ham which you stridently assert is perfectly safe to eat. What? You're not going to do that? Then *stop* giving irresponsible advice. – May 04 '11 at 00:11
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6@daniel - Growth rates of pathogens is _not a mystery_. You're acting like the entire medical research profession doesn't exist (not to mention food safety research). Maybe it's a mystery to _you_, but that's not a reason to get all frantic. Meat sitting out for 9 hours _at 50F_ is not the same as meat that's been sitting out for 9 hours _at 80F_ because growth rates are very different at those temperatures. Since you seem unwilling or unable to grasp this, there really isn't anything left to discuss. (Incidentally, if I pay for any medical bills, will you pay for all the wasted hams?) – Rex Kerr May 04 '11 at 13:01
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4@daniel The "four hours in the danger zone" rule isn't hard and fast; it's more of a rule of thumb. If you've ever eaten a tough cut of meat prepared at a modern restaurant, chances are it was cooked at 55°C for a few days. If done properly, the meat can be effectively pasteurized. The actual "danger" is a much more complex function of time, conditions, and not only temperature but more importantly the change in temperature over time. – ESultanik May 04 '11 at 16:58
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1Might I suggest that number of bacteria is not the only (even primary?) concern? One does not get sick purely from consuming bacteria, but from the toxins produced by the bacteria. 9 hours may mean only double the bacteria, but I would posit that that does not translate to double the risk. Consider the amount of toxins that can be produced in that time when you're weighing the risks in giving public advice. – Ray May 04 '11 at 17:09
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2@Ray Every toxin that is produced by food borne pathogens of which I know is either (1) destroyed by subsequent heating, *e.g.*, botulinum toxin, or (2) is only produced within the human's digestive system as a result of consuming the pathogen itself, *e.g.*, clostridium perfringens. The only heat-stable toxin of which I know that also is produced within the food itself is due to staphylococcus aureus, however, if the food was handled properly then there should be little (albeit non-zero) risk. – ESultanik May 04 '11 at 17:33
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1@Ray - I've updated my answer to more thoroughly document why this also is not a major concern. – Rex Kerr May 04 '11 at 17:54
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2@ESultanik - And _S. aureus_ is almost entirely impotent to produce toxins at 10C. See http://www.ncbi.nlm.nih.gov/pmc/articles/PMC380837/pdf/applmicro00055-0194.pdf figures 1 and 2. – Rex Kerr May 04 '11 at 18:00
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2+1 for every fact citing, rational response. My long experience cooking large chunks of meat suggests that it is nearly impossible to take a piece of meat from 165F to 35F in a timely way. And the methods for speeding the process (slicing/boning/etc) introduce environmental bacteria throughout the meat. – Satanicpuppy May 04 '11 at 18:31
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Can you categorically state this meat is safe? No, you cannot. Again, one of us cares about someone else's health and safety and is providing advice in line with established safe food handling practices. One of us is not. Unless you are willing to take responsibility for the ill effects your terrible advice can cause, you need to stop this. – May 04 '11 at 19:48
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@ESultanik: "The "four hours in the danger zone" rule isn't hard and fast; it's more of a rule of thumb. " <--this is beyond wrong. It is absolutely a hard and fast rule. "If you've ever eaten a tough cut of meat prepared at a modern restaurant, chances are it was cooked at 55°C for a few days." <--- this has no relation to reality. One of us *works* in a restaurant, ESultanik, and I suspect it's not you. – May 04 '11 at 19:49
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1@daniel Do you deny that restaurants cook tough cuts of beef sous vide for 24+ hours at 55°C? Because, if restaurant's do---which is the case by my experience---then that invalidates the hard-and-fastness of the "four hours in the danger zone" rule. – ESultanik May 04 '11 at 20:09
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At 55? No, because that will not cook the beef through. 140F/60C is the internal temperature for rare beef, so you're going to be cooking sous vide at that or higher, out of the danger zone. – May 04 '11 at 20:50
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2@all: Please continue further debate/discussion/commentary regarding this in [chat](http://chat.stackexchange.com/). – hobodave May 04 '11 at 20:57
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I agree with Rex Kerr generally. You should use extreme caution with it, but if it is cooked thoroughly, it should be fine in that time frame and at that temperature. I would avoid eating it without cooking it. – dwaz May 03 '11 at 04:26
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This is a ham right? Not a bone-in cooked pork butt, but an actual cured ham?
This falls into the category I like to call "Things I personally would eat, but wouldn't feed to anyone else." Chances are it's fine. 80 years ago they'd have thought nothing of it, but in our modern bacteria-obsessed culture, a few hours sitting on the counter is certain death. It was cooked, it was cured, it's probably okay. Hell, I've eaten cheesecake that's sat out the same amount of time, and the food nazis'll have you putting those in the fridge before they're even cool (which I know the professionals don't do, since that makes them crack like the grand canyon.)
On the chance that it's not okay, I wouldn't feed it to anyone else. And if you're going to eat it, I'd eat it quick. It certainly doesn't have as much shelf-life left.
Edit: My usual harp is on cooking temperatures (the recommended ones are all too high for me), but bacterial growth is another sore point. People will tell you a side of beef stored at 36F for a week must be used, frozen, or thrown away, and they'll tell you that, if you dare to cook it, it must be cooked well-done. But a high-end steakhouse will store it for three to four weeks at the same temperature, and sell you the finest steak you've ever eaten (cooked medium-rare) for 30 bucks a pound.
Sure, you can get unlucky and a random wrong bacteria can land on your food, multiply, and cause trouble. That's why they make the rule, so you're going to be safe 99.9% of the time. Like eggs. Raw eggs are killers, right? It's estimated that 1 in 14000 eggs has salmonella contamination, but that means 99.99997% of the time, you're fine to eat them raw. Don't take foolish risks, but don't let paranoia ruin your enjoyment of food either.
Satanicpuppy
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It's notable that we don't cure ham like we used (though I still doubt that it's dangerous). – Brendan Long Jan 16 '12 at 01:49
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@brendan: Well, we *do*, but this isn't that kind of ham. Still, in this situation, the curing we *do* do, plus being cooked, plus the house being cool, I wouldn't have any problem eating it. – Satanicpuppy Jan 18 '12 at 14:40
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If the ham picked up anything like botulinus then the toxic waste products are not destroyed by re-cooking... so the ham would remain toxic.
So the safe advice would be to throw it away.
And from a self-preservation point, I can't possibly advise anything else.
However, ham is full of preservatives (that's why it's ham not pork!) and it's probably safe to eat as is... but it's YOUR risk and your should NOT feed it to anyone else without them accepting that they are doing something risky and (nowadays) unusual. Playing russian roulette with your health is YOUR call, playing it with your children's health (or yoru spouse's health) is emphatically NOT your call.
Matt
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In most parts of the world Botulism is very rare (though still very dangerous). It should not form on correctly cured hams as they are very salty at surface level and should be quite dry. It also requires anaerobic (wet) conditions. So a ham in a cloth at 10°C is not an ideal candidate. I would not same the same about store sliced ham etc – TFD May 04 '11 at 11:19
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1Ham is typically cured with sodium nitrite, which has historically been used specifically to block botulism growth. Not that there is no risk, but that's probably not the primary bacteria to consider. That said, listeria, e. coli., salmonella, etc., all work in the same way (though their waste products aren't quite as deadly). They produce toxins that remain after the bacteria has been destroyed. – Ray May 04 '11 at 17:14
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2Botulinum toxin is denatured at 60°C; as long as that temperature is achieved for a sufficient period of time (or a higher temperature for a shorter period of time), the "toxic waste products" will almost certainly be destroyed. – ESultanik May 04 '11 at 17:39
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2@ESultanik: Botulinum toxin is actually one of the easiest to get rid of. Most protein toxins are far more difficult to inactivate and require food to be cooked to ash, or at least to a flavourless mass. Examples: E.coli O157:H7 encodes an SLT or STX which just *starts* to denature after 5 minutes at 95° C, diphtheria toxin needs to be subjected an autoclave or chlorine bleach to inactivate, and I'm not even sure what the parameters are for CdtB. All of these are capable of being produced by bacteria *on* the food, just not quite as fast as they are within the GI tract. – Aaronut May 05 '11 at 14:52
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No. It is garbage. There is a chance that it might be okay, but given the nasty bacteria that could be there, and the less than stellar track record of US food producers in recent years, it is simply not worth the risk.
@mfg, no difference.
Throw it out.
hobodave
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7What nasty bacteria would this be? This is a home environment. It was a fully cooked ham, so at that point it was essentially sterile. The only bacteria that would likely come in contact with it would be home based human host bacteria, which at reasonable levels will be fine and good for you. At 10°C, by the book raw meat takes 2 days to spoil (twice as fast as 4°C), as only a few types of bacteria can grow that cold – TFD May 03 '11 at 09:10
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Could be anything. The OP doesn't state whether it was purchased cooked or cooked at home. If the former, could be contaminated with literally anything--listeria e.g., and anyone remember e. coli on spinach? And yet again: basic safe food handling practices indicate that this is emphatically not safe to eat. – May 03 '11 at 09:35
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3Could well be absolutely fine for that sort of short time, many people take ham sandwiches to work that end up in a more ideal growth environment for just as long with no major issues. If he is recooking it too, then that will kill off any bacteria that could be on it if done properly. – Orbling May 03 '11 at 20:39
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1Nine hours is radically different from the four or so that a sandwich will be left in a lunchbox. But whatever, a professionally-trained chef knows nothing about food safety of course. – May 03 '11 at 21:32
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1A professionally trained chef's job includes protecting their employer from food safety-related liability. I would be willing to bet that your advice is spot-on for anyone running a restaurant. "Best practices" tend to be admired in legal circles whether or not they are necessary for the case being considered; if you follow best practices, the judge and jury do not have to think about the issues--you did "the right thing", and therefore even if harm accrued, it was not your fault, so you're usually not liable for anything. (Proving the harm was not your doing is usually harder.) – Rex Kerr May 03 '11 at 23:41
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5@daniel That's nine hours at 10°C. Check your food hygiene tables, that is only twice the decay rate as at 4°C. So equivalent to 18 hours in the fridge, therefore not a problem. Yes in a commercial operation you would toss it out and sack the slacker whom left it out! – TFD May 03 '11 at 23:49
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3A professionally-trained chef's job is to ensure that people treat food carefully. It is unwise to advocate that people should go ahead and do risky stupid things that can severely impact their health. – May 04 '11 at 00:02
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5I reverted your latest edit daniel. The sarcasm isn't really necessary in your answer. Besides, I voted for your original answer, not the sarcastic edit :P – hobodave May 04 '11 at 16:05
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At home, If the ham was left out, I would be more concerned with its environment given these timeframes. Was it covered, human/pet/insect Traffic, was it handled/sliced, served or whole, etc. If it was fully cooked, uncut/unserved, covered, and at room temps, I would eat it and even serve it to family. There are other risks that exceed the risk of spontaneous spoiling in the first 9 hours, i'd bet there is a better chance you would choke on it than get sick.
If it was a business I'd toss it or give it away. I used to throw out foods I KNEW were ok, just because it looked or smelled funny. Only because I didn't want to even deal with any questions. Distractions usually end up costing more than materials.
FWIW, my2cents
d0c5i5
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Do not eat it. It will most likely have bacteria in it, making unsafe to eat.
TheDoctorplus1
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8Lots have things have bacteria in them that we eat, often deliberately, yoghurt for instance, it is not a blanket "issue". – Orbling May 03 '11 at 20:37