Ever made huge pots of beans or soup or whatever and wondered whether to let the pot sit out before sticking it into the refrigerator? Here’s a useful piece of advice from the Sacramento Bee‘s food section:
Basically, you want to get the food below 40 degrees as soon as possible. There are a few ways to do that. You can spread the food out in a wide, shallow pan, to expose as much of it to air, cooling faster, or you can put a sealed double plastic bag filled with ice into the center, which also helps get rid of some of the fat (it sticks to the bag when you pull it out). Or, if you’ve got a free sink, fill it with ice water and float the pot in the middle. Then refrigerate it once it’s cool.
Basically, I want to laugh. Dirty up more dishes? Waste plastic bags? Fill the sink with ice water?
Who on earth do they really think is ever going to follow this advice? It’s a lot easier to just heat up leftovers enough to fry the bacteria before eating it, and the CDC says that 160 degees F works.
The way that food is handled after it is contaminated can also make a difference in whether or not an outbreak occurs. Many bacterial microbes need to multiply to a larger number before enough are present in food to cause disease. Given warm moist conditions and an ample supply of nutrients, one bacterium that reproduces by dividing itself every half hour can produce 17 million progeny in 12 hours. As a result, lightly contaminated food left out overnight can be highly infectious by the next day. If the food were refrigerated promptly, the bacteria would not multiply at all. In general, refrigeration or freezing prevents virtually all bacteria from growing but generally preserves them in a state of suspended animation. This general rule has a few surprising exceptions. Two foodborne bacteria, Listeria monocytogenes and Yersinia enterocolitica can actually grow at refrigerator temperatures. High salt, high sugar or high acid levels keep bacteria from growing, which is why salted meats, jam, and pickled vegetables are traditional preserved foods.
Microbes are killed by heat. If food is heated to an internal temperature above 160°F, or 78°C, for even a few seconds this sufficient to kill parasites, viruses or bacteria, except for the Clostridium bacteria, which produce a heat-resistant form called a spore. Clostridium spores are killed only at temperatures above boiling. This is why canned foods must be cooked to a high temperature under pressure as part of the canning process.
The toxins produced by bacteria vary in their sensitivity to heat. The staphylococcal toxin which causes vomiting is not inactivated even if it is boiled. Fortunately, the potent toxin that causes botulism is completely inactivated by boiling.
Posted in Writing because someone‘s bound to get a story idea about food poisoning.