Hot Pot, Cold Fridge: What's The Deal?

There are a lot of misconceptions about putting hot food in the refrigerator. Some people believe that it will spoil the food, while others think that it will harm the appliance. However, according to food and health agencies in the US, these are all myths. In fact, not putting hot food in the fridge could put you at risk of foodborne illness.

The danger zone for food is between 40° and 140° Fahrenheit (or 5° and 57° Celsius). This is the temperature range in which harmful bacteria, such as E. coli, Staphylococcus, Campylobacter, and Salmonella, grow rapidly. To prevent this, food must be refrigerated within two hours of cooking.

While it is safe to put hot food in the fridge, large amounts of hot food can raise the temperature of the fridge to the danger zone. To avoid this, it is recommended to divide large batches of food into smaller containers to help them cool faster. An ice bath can also be used to chill leftovers before placing them in the fridge.

It is a myth that hot food will spoil other food in the refrigerator

This advice contradicts previous guidance. For example, the US government's War Department Technical Manual from 1942 specified that hot food should be allowed to cool to room temperature before being placed in the refrigerator. However, by the second half of the 20th century, official guidance had changed, with the FDA declaring that food should be refrigerated as soon as possible.

While it is true that placing hot food in the fridge can temporarily raise the appliance's ambient temperature, modern refrigerators are capable of rebounding from this increase. To help hot food cool faster in the fridge, it is recommended to divide large batches of food into smaller or shallower containers. An ice bath can also be used to speed up the cooling process before placing food in the fridge.

Of course, how you chill food in the fridge is a matter of preference and depends on the type of food. For example, foods with a crispy top, like a pie or baked mac and cheese, can be chilled uncovered or lightly covered with a clean cloth to prevent condensation from forming and affecting the texture.

Hot food should be put in the fridge within two hours of cooking

It is important to refrigerate hot food within two hours of cooking to prevent foodborne illnesses. This guideline also applies to reheated food or food that has been kept warm in an oven. Perishable cold foods, such as deli meats and cheeses, should also be treated with the same urgency.

While it is safe to put hot food in the refrigerator, it is important to be mindful of the quantity of food. Large amounts of hot food can raise the overall temperature of the refrigerator, creating a “danger zone” where harmful bacteria, such as E. coli, Staphylococcus, Campylobacter, and Salmonella, can thrive and multiply. To avoid this, it is recommended to divide large batches of food into smaller portions and place them in shallow containers for quicker cooling. An ice bath can also be used to rapidly chill food before placing it in the refrigerator.

It is worth noting that the longer food is left out, the higher the risk of bacterial growth. Therefore, it is crucial to prioritise refrigerating hot food as soon as possible. If you are forgetful or won't be around to store the food after it has cooled, it is better to put it in the refrigerator immediately rather than risk leaving it out for too long.

Additionally, when refrigerating hot food with a crispy top, such as a pie or baked mac and cheese, it is recommended to leave it uncovered or lightly covered with a clean cloth to prevent condensation from forming and affecting the texture. Once the food has chilled, it can be wrapped or stored in an airtight container.

By following these guidelines, you can ensure that your hot food is safely stored in the refrigerator and reduce the risk of foodborne illnesses.

Large amounts of hot food should be divided into smaller portions and put into shallow containers

While it is safe to put hot food in the refrigerator, it is not advisable to put a large amount of hot food into the fridge all at once. This is because it can take a long time for a large amount of hot food to cool down, and during this time, the food can stay in the "danger zone" for bacterial growth—between 40° and 140° Fahrenheit (or 5° and 57° Celsius)—for too long, increasing the risk of foodborne illnesses.

To avoid this, it is recommended that large amounts of hot food be divided into smaller portions and placed into shallow containers. This will help the food to cool down faster once it is in the fridge. The recommended depth of food in these containers is three inches or less.

To further expedite the cooling process, you can place the containers in an ice bath or run them under cold water before putting them into the refrigerator. This will help the food pass through the danger zone for bacterial growth more quickly. It is important to note that an ice bath or cold water shower is not necessary for the food to be safely stored in the refrigerator, but it can help speed up the cooling process.

Additionally, when storing hot food in the refrigerator, it is recommended to loosely cover the food with something like parchment paper until it is cold. This will help address cross-contamination concerns while still allowing for adequate cooling. Once the food is chilled, it can be wrapped with plastic wrap or aluminium foil to help extend its shelf life.

Refrigerators should be set to 40°F or lower

Refrigerators should be set to a temperature of 40°F or lower to prevent bacteria from multiplying. The U.S. Food and Drug Administration (FDA) recommends that your refrigerator temperature should be at or below 40°F, and your freezer temperature at or below 0°F. However, the ideal refrigerator temperature is slightly lower, between 35° and 38°F (or 1.7 to 3.3°C). This temperature range is as close as your refrigerator can get to freezing without freezing your food.

Bacteria, such as E. coli and Salmonella, multiply rapidly at temperatures above 40°F. Setting your refrigerator to 40°F or lower will help to keep your food fresh and safe to eat for longer.

It is important to note that not all refrigerators have accurate temperature gauges. Your refrigerator may be a few degrees off the mark you set, so it is recommended to purchase an appliance thermometer to ensure your refrigerator is at the correct temperature.

Additionally, it is advised to let hot food cool down a bit before storing it in the refrigerator. This is because hot food can raise the temperature inside the refrigerator, creating an environment for bacteria to multiply. However, it is important not to let the food cool down to room temperature, as this increases the risk of foodborne illness. Instead, divide large batches of hot food into smaller containers to help them cool faster, and then place them in the refrigerator.

Containers should not be stacked on top of each other in the fridge

While it may be tempting to stack containers on top of each other in the fridge, especially if you're running out of space, it's important to avoid doing so. Here are several reasons why you should avoid stacking containers on top of each other in your refrigerator:

Impaired Ventilation: Stacking containers can block the fridge's ventilation system, hindering proper airflow. This blockage can cause the appliance to work harder to maintain its temperature, leading to increased energy consumption and higher electric bills.

Food Safety: Stacking containers can create an environment conducive to bacterial growth. The lack of proper airflow between containers can result in pockets of warmer temperatures, providing an ideal environment for bacteria to thrive. This increases the risk of foodborne illnesses.

Spoilage and Food Quality: Inadequate airflow due to stacked containers can lead to uneven cooling and affect the overall quality of your food. Certain foods, such as crispy dishes or baked goods, can become soggy due to condensation. Additionally, stacking containers can make it challenging to maintain proper food rotation, potentially leading to food spoilage.

Difficulty in Accessing Items: Stacking containers can make it cumbersome to access the items you need, especially those at the bottom of the stack. This inconvenience may cause you to spend more time rearranging items and could result in spills or broken containers if you're not careful.

Limited Visibility: Stacking containers can obstruct your view of the items inside the fridge. This can lead to forgotten leftovers, hidden expired products, or difficulty in finding what you need, ultimately resulting in food waste.

To ensure food safety and maintain the optimal performance of your refrigerator, it is best to avoid stacking containers on top of each other. Instead, utilise other storage methods, such as using shelves, drawers, or containers of varying sizes, to maximise space efficiently without compromising ventilation and food quality.

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