Macheesmo declares the most important step to proper food freezing is to cool it down first. Putting warm or hot food directly into your freezer runs the risk of lowering the freezer’s overall temperature, which may begin the defrosting process for other frozen items. While the need to cool small portions of hot food before popping them in the refrigerator may be a myth, there’s more safety at stake with the science occurring in your freezer. It’s an issue for two reasons. First, the previously frozen foods can enter the temperature “danger zone” where bacteria wake up and begin to multiply rapidly (40 to 140 degrees Fahrenheit, per the FDA). Macheesmo notes that it will also take the warm or hot food you put in the freezer much longer to freeze, once again opening the door to the danger zone.
One thing to remember — there are two foods that should never be frozen, regardless of temperature: canned foods still in the can, and eggs still in their shells (per FDA). If you have some leftover Chef Boyardee that you want to freeze, though, that’s fine — just pop it in the fridge until it’s cooled off, then transfer it to the freezer.