Food storage requires great care, as errors can lead to bacterial contamination with potentially serious consequences. The question that often comes up is:can you put hot food in the fridge? While very few scientific studies have looked at the issue, several health authorities have issued recommendations regarding methods of storing hot foods as well as the different times during which they can be left outside the refrigerator to cool.
Some people insist that leftovers should be kept out of the fridge until they reach room temperature, while others are fine with putting them in the fridge while they're still a bit warm. . So, who is right ? Is one method safer than the other, or are they equivalent? There are several things to consider, including the safety of the food in your leftovers and the safety of your food already stored in the fridge.
First, although it should be avoided, hot food can be placed in the refrigerator according to the Washington state Department of Health . Large quantities of food should be divided into small portions and placed in shallow containers for faster cooling in the refrigerator. In fact, hot foods placed in large containers will take much longer to cool.
And this can be problematic for two reasons. The first is that the heat released by the dish, if it is too high, can be communicated to the surrounding food and cause it to deteriorate more quickly. The second is that the internal temperature of the refrigerator may increase due to the condensation effect, and your appliance will have to spend more energy to rebalance the temperature.
This also applies to the freezer, in which it is strictly inadvisable to place food that is still hot. As the temperature is much lower than in a refrigerator, there is a significant risk of thermal shock which can cause other foods to defrost and damage the internal coating of the freezer.
However, leaving food to cool at room temperature for too long is also dangerous, as it risks the proliferation of several pathogenic bacteria (Staphylococcus aureus , Salmonella Enteritidis , Escherichia coli O157:H7 , and Campylobacter ) at levels that may endanger health.
According to the United States Department of Agriculture , there is a range of temperatures between 4°C and 60°C, called the “Danger Zone”, in which bacteria proliferate extremely quickly. Between these temperatures, the number of bacteria doubles approximately every 20 minutes. This is why the authorities have established two recommendations:below 32°C, food should not be left outside for more than 2 hours; and above 32°C, no more than one hour.
Foods kept outside the refrigerator for too long therefore risk becoming contaminated, and also contaminating the foods stored in the refrigerator. It is also not recommended to cool your food outside your home (on an easily accessible window sill, for example). The outside temperature is variable and can, in some cases, change within minutes. And animals could put the food at risk of bacterial contamination.
