Really? 
We routinely leave food on the counter all day. We cook in the morning, leave the dish (covered) on the table before leaving for work/school. When we get home, we usually eat the food at room temperature. We rarely bother to heat it up anymore. I’ve never gotten sick from it, as far as I know, and we’ve been doing it as far back as I can remember.
Am I in impending danger from food poisoning?
I hope not. I often take lunch to work then don’t get around to eating it then either eat it for dinner or put it in the fridge then eat it at work the next day. Usually it’s stuff like pizza or cold cut sandwiches with no condiments, so I’m not too worried but today it was chili. No bad effects so far but heartburn (worth it, though).
Really it depends on the level of risk you are willing to take. If you are healthy there is very little chance that a round of food poisoning will kill you. But it won’t be fun.
Most food guidelines are created to (nearly) eliminate the risk of food poisoning. These guidelines go above and beyond the “normal” precautions that we’ve developed through thousands of years of trial and error. So you just have to figure out what your acceptable risk level is.
Me, I eat anything. And now and then I get food poisoning and it sucks.
Plus USDA/FDA food guidelines are also aimed at restaurants and others who serve food to a lot of people. One person getting food poisoning at home is misery for one. 50+ people getting food poisoning from your restaurant is potential career suicide, restaurant shut down by the Board of Health, etc.
That being said, it’s not that tough to just put the food away in the fridge or freezer after it’s cooled to a reasonable warm temp. No one’s asking you to autoclave it, add antibiotics, handle it with tongs only, or use sterile procedures, it’s picking up the container and putting it in the fridge.
Cooking food may kill most bacteria, but not necessarily all, and it does not do a thing to the toxins that bacteria produce while they’re happily multiplying on the feast you’ve provided them.
Personally, my guide is whether the time involved in putting the food in the fridge - or the worth of the food for eating, if I’ve forgotten to put it away - is more valuable to me than potentially getting ill. I rarely have problems with food that way, but did get food poisoning from take-out restaurant food a few months back. (The food seemed fresh and was hot, so it wasn’t that I left it out or anything.) I was feeling yucky later that night and by the next morning I really was not well, and had to take the day off work, spending at least half of it on the toilet and most of it in misery. Sometimes you can’t avoid food poisoning, so why intentionally risk getting it?
there is no such thing as the 24 hour flu-
or so the story goes.
cook it, eat it, refrigerate the rest. I mean its not like we dont have microwaves or something.
Under ideal conditions, bacteria divide every twenty minutes. So a single bacterium in a dish of food placed on a table at 8 A.M. and left there could be 64 bacteria at 10 A.M., 4,096 at noon, 262,144 at 2:00 P.M., 16,777,216 at 4:00, and a stomach-churning 1,073,741,826 bacteria at 6:00 P.M.
A better question than “why discard after two hours?” might be “how can the OPer not get food poisoning all the time?”
I second the recommendation to put the food in the fridge.
Not all bacteria are pathogenic. If the ones colonizing the food are not pathogenic, and they reproduce and are initially in more quantities than whatever stray pathogenic bacterium that may have survived cooking, then enough of them may not be formed in that time frame to cause disease.
Bacteria commonly associated with food poisoning (Salmonella, C. jejuni, E. coli, L. monocytogenes, B. cereus, L. monocytogenes) have different niches, environments and pathogenic levels. This means that some bacteria may cause disease at different concentrations than other bacteria.
The health of the individual is also important. For example, Listeria monocytogenes is not usually considered a big deal except in the old and immunocompromised, when it can be fatal, or in pregnant women, when they can cause miscarriages.
That said, yea, put the food in the fridge and zap it again when you want to eat it.
Cooking in the morning and leaving it at room temperature all day is skirting the ragged edge of how long you can safely leave food out. As others have mentioned, cooking does nothing to elmimate any toxins in the food, and only fridge temperature discourages bacterial growth (but as also mentioned, it only takes one). I have on occasion forgotten food on the stove overnight and ate it the next day (early the next day - no need to increase risks) with no ill effects, but I wouldn’t make a habit of it. When you learn about what media are used to encourage the growth of bacteria and you realize your FOOD is a very good medium for them, you get more careful with that stuff.
Wow. I never thought it was that big of a deal. My mom has always done it that way and none of us have had to be hospitalized. Yet. Huh. We must have pathogen-proof stomachs, but, as most of you have pointed out, why take the risk? I guess I’ll have to get a microwave now. Reheating food on the stove is a total PITA.
Do I have to wait for the food to cool before I put it in the fridge? I am obviously woefully ignorant of food safety guidelines.
IIRC, most food poisoning cases don’t require hospitalization.
I would let it cool down somewhat, so it’s comfortably warm or lukewarm. If you put hot food in the fridge, you heat up the fridge and all the food around it, wasting energy and risking letting bacteria grow on the food in your fridge too.
As KarlGrenze pointed out, you may be fortunate enough in that whatever was growing in the past wasn’t harmful to humans. I think that if you do happen to lose out on the bacterial lottery and something nasty out-competes the other stuff, one bout of food poisoning will convince you it’s not worth the risk.
I’ll point out that as a homebrewer, I mix up a basically sterile batch of yummy bacterial food (“wort”, or a roasted barley ‘tea’ with hops added) and leave it out at room temperature for days or weeks. Hops have some antibacterial properties, but homebrewers hedge their bets by dumping a whole ton of brewing yeast into the batch and letting that go crazy. If you’ve followed good sanitation practices and your yeast is healthy, all should go well and it should outcompete anything nasty that will make your beer taste yucky and maybe your stomach turn.
I think the key to this is the type and form of the food relative to the time. For example, I probably wouldn’t worry about soup sitting out for two hours because of its salinity and/or acidity. I might get worried about a Helllman’s Potato Salad with Hard Boiled Eggs, but not a vinegary sweet coleslaw. Now, Raw ground meat sitting for two hours… might be a problem.
I believe personally you can build up tolerance to the bacteria. My father is very tolerant of how old food can be and still be acceptable to eat. The man has a stomach of iron and never gets sick. He eats lunch meat that you can smell turning. It turns my stomach to watch him. I swear he’s made himself invulerable to most bacteria over the years. Either that or he’s a very, very lucky man who should buy a lottery ticket immediately.
I read recently that putting the food in a dish and then putting the dish in an ice water bath will reduce the temp of the food faster than just setting it in the fridge, with water being a better conductor of heat and all. You might try that if you don’t have time to get it to room temp to put it in the fridge before you have to leave in the morning. Even if you have to put the dish and it’s ice water bath in the fridge to cool, it would be better than leaving it out all day.
Hell, my wife threw away leftover Thanksgiving turkey and ham (a Honey-baked ham, nonetheless) because, gasp(!), the meats sat out during dinner. :rolleyes:
It’s not the re-heating that’s the issue, it’s the food sitting out and incubating all day that’s the problem. As a former microbiology tech, let me put it to you this way; if you make a beef soup in the morning, and leave it on the stove so it is warm then at room temperature all day, you have created an almost perfect medium of growth for some very common bacterial pathogens. Labs make efforts to create these conditions to encourage bacterial cultures to grow. A lot of your common bacteria grow into nice big colonies overnight; you’re giving them almost as long on your stovetop.
On re-reading, I see that you are probably saying that you’ll start putting the food in the fridge before going to work. Here is a website with basic food safety tips (to ease your mind that we’re not all just making stuff up here 
). With regard to cooling food before putting in the fridge:
(4ºC to 60ºC being 39ºF to 140ºF. You may note that room temperature is in the middle of that range. Most fridges are at about 4ºC or 39ºF.)
Just make sure that you heat it thoroughly when you nuke it. Stirring the food is critical for insuring evenly heated leftovers. Otherwise, you just encourage bacteria growth. I’m constantly after my spouse about making sure the food is HOT before she eats it. Well, that and trying to convince her after 16 years, goddamnit, that she doesn’t have to turn the burner on high to melt butter, and that you never leave the kitchen with a burner above simmer, goddamnit. We’ve had three kitchen fires and two melted pots because of this.
A lot depends on the food. When I grew up, we had bacon, eggs and biscuits for breakfast. Leftover bacon and bicuits were left on a plate at room tempature on the stove. They would sit there until I devoured them when I got home from school.
Eggs were never kept in such a manner. Nor anything with mayonaise.