Don't put hot food in the refrigerator

[snopes]

Q. I remember my grandmother would let food cool down on the counter before storing it in the refrigerator. Someone told me that you should never put hot food in the refrigerator as germs/bacteria would multiply. Is this true? Is this an urban myth?

http://www.jsonline.com/story/index.aspx?id=747500

[Troberg]

I doubt it. Cooling is cooling, there is nothing magical about cooling it in a refrigerator.

There might be another reason for it, though, which coincidentally is the reason I havn't put some servers into my freezer even though it's exactly the correct size for 19" rack servers. The fridge is made to keep stuff cool in an insulated environment, with the door opening a few times each day. Put hot food in it (or a bunch of servers that each constantly burn off a couple of hundred watts) and it will have to work much harder, wearing down the compressor unit faster.

[songs78]

Proper technique is to cool in an ice bath. Cooling in a refrigerator is better than cooling on the counter but it also increases risk to other food near the hot food.

[stagemanager0610]

I vote for no on the bacteria - I put food in the fridge right away to cool it off, weather it's cooling to eat faster or to store. I haven't gotten sick off of doing that, so I doubt that it increases the risk of illness. YMMV of course.

[Four Kitties]

I also vote no on bacteria (exactly the opposite, in fact), but I can think of several reasons off the top of my head why not to put hot food in the fridge:

• It could heat up the fridge, putting the internal temp over 40F and placing everything else in there at risk for bacterial growth
• I have a glass shelf in my refrigerator: the temp shock of a hot container on cold glass might shatter it
• If food cools uncovered before being refrigerated, there is less condensation to make the food soggy.

Four Kitties

[Hapax Legomena]

The reason my mother always gave for not immediately putting hot food in the fridge was to avoid condensation. Several years ago I was told by a woman who worked for the local health dept. that hot food had to be cooled down as quickly as possible by putting it into a fridge and the idea that it would "make the fridge work harder" was a holdover from the days of actual iceboxes in which the block of ice would melt faster if hot food was put inside. According to her, modern refrigerators have no problem dealing with hot foods and there is no risk to anything else inside.

[RichardM]

"Having no problem" with the added work to cool some thing hot in the refrigerator is not the same as requiring extra electrical energy to cool something hot in the refrigerator. In others, just because the refrigerator can handle the load doesn't mean you should do it. Speaking as an electrical engineer, not a food specialist of any sort (well I do like food), I recommend air cooling first, then refrigerating.

[Grand Illusion]

My grandmother observed this rule. Back then, everyone used the old glass mayo and jelly jars with metal lids to store leftovers in the fridge, Her rationale was that condensation would cause the metal in the lids to rust.

[Arriah]

Your refrigerator will use more energy to cool food from 140° than it will if it only cools the food down from 90° so if you're worried about energy consumption, that's a consideration. If it's cold outside and you're running your heater, it can save some energy that way as well. However, if it's 95° outside and you're running the AC it's probably a wash. There is also the magical 4 hours for food to be between 40° and 140° so if you're saving 5 cents on electricity but risking spoiling $5 worth of food it's a different matter.

(All temperatures made up for clarity)

[lynnejanet]

I think this is also a holdover from the days before frost-free refridgerators and freezers. Modern refridgerators extract the excess moisture from the fridge, so there's no excess condensation.

This advice is in direct contradiction to what you are supposed to do with chicken, in particular. According to health departments everywhere, poultry should never be allowed to cool down at room temperature, but should go as soon as possible into the fridge, to avoid bacterial growth.

[Troberg]

There might be another reason for it, though, which coincidentally is the reason I havn't put some servers into my freezer even though it's exactly the correct size for 19" rack servers. The fridge is made to keep stuff cool in an insulated environment, with the door opening a few times each day. Put hot food in it (or a bunch of servers that each constantly burn off a couple of hundred watts) and it will have to work much harder, wearing down the compressor unit faster.

I found the manual to my freezer, and there is no way it could handle it if I stuffed it full of file servers, but it should certainly handle reasonable amounts (ie, don't tip it onto it's back and pour it full of boiling soup) of hot food without problem.

[snapdragonfly]

Originally Posted by lynnejanet

I think this is also a holdover from the days before frost-free refridgerators and freezers. Modern refridgerators extract the excess moisture from the fridge, so there's no excess condensation.

This advice is in direct contradiction to what you are supposed to do with chicken, in particular. According to health departments everywhere, poultry should never be allowed to cool down at room temperature, but should go as soon as possible into the fridge, to avoid bacterial growth.

Yes - as far as food spoilage goes, leaving it to cool at room temp is definitely unpreferable to getting it immediately in the fridge. The faster you can get food out of the danger range (bacteria like the same temperatures we do - not too hot or too cold) the better. Either keep food hot or get it cold right away.

You need to sort of, you know, not put a hot pot right on top of something perishable, and I would transfer the food into a fresh, cool container rather than putting a hot casserole dish or pan into the fridge, for sure. But my mom the home economist agrees with lynnejanet.

~back when she was still working they had to do the turkey hotline at Thanksgiving and people would get mad when they called and asked "we left the turkey out overnight, is it still safe to eat?" and were told no. "But that's wasting FOOD!" my mom just wanted to say, fine, get food poisoning then, see if I care. But of course she didn't. Not to them, anyway.

[Arriah]

Originally Posted by snapdragonfly

~back when she was still working they had to do the turkey hotline at Thanksgiving and people would get mad when they called and asked "we left the turkey out overnight, is it still safe to eat?" and were told no. "But that's wasting FOOD!" my mom just wanted to say, fine, get food poisoning then, see if I care. But of course she didn't. Not to them, anyway.

Wow. That's just an impressive amount of... something bad. I could understand asking about 6 or 7 hours since that's sortof borderline but overnight? The refrigerator was invented for a reason people.

[bjohn13]

Songs78 had it. The proper technique, according to our state health department, is to cool down hot food in an ice bath before transferring to the refrigerator.

An ice bath is actually slightly cooler than a refrigerator, and it will actually cool hot food down a little bit more quickly. The real danger, though, comes from hot food being placed in the vicinity of other perishables, which will then raise in temperature for the duration of the time it takes for the hot food to cool down. Don't believe me? I once had a vat of margarine start to melt when I put a 24-pack of Diet Coke that had been sitting in the sun all day long on the shelf immediately below it.

We also had thermometers placed in several different locations in our walk-in cooler when I worked at a local Denny's several years ago. It was actually quite common to find the area around warm items that had been recently placed in the cooler five to ten degrees warmer than other areas in the cooler unless the recently placed items were right next to the condenser.

Plus, the whole energy concept is a wash. For one thing, I'd never cool anything down on the counter (without an ice bath) before transferring it to the fridge. However, if cooled the proper way (by an ice bath), one would probably be paying more in energy costs for the ice in the ice bath than to run the refrigerator condensor a little longer.

[Sly Dog]

Well, my Grandmother used to say the same about not putting hot food in the fridge but I always figured it was because for much of her life she didn't have a fridge, she had an ice box. When she wanted to cool something down fairly quickly she would put it in the "spring house".

[Silkenray]

Originally Posted by Four Kitties

I have a glass shelf in my refrigerator: the temp shock of a hot container on cold glass might shatter it

I have had this happen.

[Mama Duck]

Originally Posted by Silkenray

I have had this happen.

My MIL had this happen. That's how I knew not to do it.

[Sunny Lea]

Originally Posted by Mama Duck

My MIL had this happen. That's how I knew not to do it.

I think most fridges I've seen recently, though, have tempered glass. Wouldn't that solve that problem?

[rosa who else]

Try putting the hot pan on top of a folded dishtowel or a trivet wrapped in a dishtowel when you put it in the fridge.