Eli5 why is it that food can be left in steamers and under heat warming lamps for hours but it harbors harmful bacteria if you leave it in a hot place like a car for a few hours?

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Eli5 why is it that food can be left in steamers and under heat warming lamps for hours but it harbors harmful bacteria if you leave it in a hot place like a car for a few hours?

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Anonymous 0 Comments

Because you’re underestimating how hot heat lamps and steam are. Or overestimating how hot a car is, but that seems less likely.

Anonymous 0 Comments

there’s a danger zone where bacteria are most harmful

food under heating lamps are constantly kept at a temperature *above* the danger zone, where bacteria die

food left in a car rapidly hits the danger zone, where bacteria multiply

Anonymous 0 Comments

In higher temperatures bacteria reproduce faster, but once temperature hits about 65 °C (150 °F) they start dying because it’s too much heat for them. The inside of a car doesn’t get quite as hot as that, but gets sufficiently warm for bacteria to reproduce very fast. Food in steamers and under lamps does get hot enough to kill off bacteria.

Anonymous 0 Comments

between 41°F and 135°F is known as the temperature danger zone, which is the perfect temp for dangerous bacteria to grow. hot steam tables keep foods above this temperature while a car sitting in the sun isnt always able to get above the temperature danger zone.

Anonymous 0 Comments

According to US food safety standards, there is the “Rule of 4”:

#Between 40 and 140 degrees Fahrenheit is safe for 4 hours.*

This applies to cars and heat lamps. Keeping food outside of that temp range is safe, as bacteria have difficulty operating/surviving.

*it’s technically between 41 and 135 degrees, but that’s harder to remember.

Anonymous 0 Comments

Your car might get hot, but it doesn’t get nearly as hot as a steamer.

You also don’t clean your car nearly as well as that steamer is cleaned.

Anonymous 0 Comments

Food is supposed to be kept at 140F in order to kill bacteria. Cars can get hot, but it’s rare for them to get THAT hot. Warm areas over 90, but below 130, are ideal conditions for bacteria growth. So a car will most likely encourage bacteria growth rather than kill it.

So if the heat source heats the food to 140 then bacteria will die and it can be left out pretty much all day. If not then the food can only be kept out for a couple of hours before it is deemed unsafe.

Anonymous 0 Comments

When I worked in food service, nothing could stay under a warning lamp for longer than 15 min. There was pretty high turnover or we tossed it, sadly. The food was so cheap produce, it only cost us a a few pennies to throw out and replace every 15 min.

Anonymous 0 Comments

I worked in a deli for years, we had to temperature probe the hot food every hour or so to make sure its internal temperature was about 60C or 65C or something.

Basically, you keep the food too hot for bacteria to survive and multiply.

Anonymous 0 Comments

Certain temperature control. At very high temperatures, bacteria is killed (about 140°F +), and at cold temperatures (40°F or below), it doesn’t reproduce.

Anything in-between allows for rapid growth of harmful bacteria. I suppose if you had a thermometer in the car to ensure it was consistently above 140°F or below 40°F, it would be OK, but we don’t generally have that.