In order to preserve foods safely, and for the longest possible time, it is important to follow basic refrigerator temperature guidelines. The basic rule of thumb to remember is that refrigeration should be occurring at temperatures of 40 degrees Fahrenheit or below.
Food that is stored at temperatures over 40 °F can quickly develop outbreaks of pathogenic bacteria. This is the type of bacteria that causes food poisoning when eaten. Clearly, these outbreaks should be avoided at all costs, as they can cause severe harm – and are sometimes fatal.
If food is kept out of the fridge for over 2 hours – or stored at above 40 °F for two hours – it should not be consumed, but instead discarded. It does not take long for any Pathogenic bacteria to present to reproduce and contaminate food stored at these temperatures.
Note there are two broad categories of bacteria that effect food. While the pathogenic type is the dangerous one, there are also spoilage bacteria. Spoilage bacteria are capable of growing at even refrigerated temperatures, and are the ones that cause visual deterioration in foods. They cause unappealing odors, textures and tastes in impacted foods.
While most people will discard visibly spoiled foods, it is important to be aware that the presence of Pathogenic bacteria – the ones responsible for food poisoning – is not always obvious. Foodstuffs can be contaminated with these organisms with no outwards signs.
For this reason it is very important to follow food storage guidelines when deciding whether a particular food item is safe to consume. Do not solely rely on your senses, as mistakes can be very dangerous.
Rather than relying solely on your refrigerators internal thermometer, it is a good idea to purchase a dedicated refrigerator thermometer to serve as a secondary check on the internal temperature of your fridge. It only costs a few dollars to buy that piece of mind.
Maintaining proper refrigerator temperatures are an important part of safe food handling procedures. They should be observed by all users of refrigeration, from the homeowner to the largest commercial applications. For more information on safe food handling contact the USDA for the latest guidelines and suggestions.