When Americans travel abroad and visit a market or grocery store, some may encounter eggs for sales nowhere near a refrigerator. The Egg Safety Center has many readers who often ask a similar question: why is it safe to eat room temperature eggs in some parts of the world, but not in the USA? The answer has to do with bacteria: Salmonella.
In the United States, it’s more than a food safety recommendation that eggs be refrigerated – it’s the law. The U.S. Department of Agriculture (USDA) determined that the best way to fight Salmonella contamination is by sanitizing the eggs before they reach the consumer. The washing process removes contaminants, but it also removes the natural coating of the egg, leaving the shell porous. On U.S. commercial egg farms, it is required that eggs are thoroughly washed and immediately refrigerated before they leave the farm and during transportation to the grocery store.
In other parts of the world, such as Europe, authorities approach the threat of Salmonella quite differently. Eggs there are not required to go through extensive washing, which leaves the protective coating on the egg. Because this coating remains on the eggs, authorities feel it is safe for them to be sold at room temperature. In some European countries, vaccines are used to prevent Salmonella in laying hens.
In America, food safety officials emphasize that once eggs have been refrigerated, it is critical they remain that way. A cool egg at room temperature can sweat, facilitating the growth of bacteria that could enter the egg through its porous shell.
Marianne Gravely, who has been answering consumer food safety questions at the USDA for 27 years explains: “Eggs shouldn’t be left at room temperature for more than two hours. There is no way to know if a shell egg is pathogen-free. Food poisoning bacteria don’t affect the taste, smell, or appearance of a food. You can’t tell if a chicken is infected with Salmonella, so any egg, whether it came from a grocery store, a farmers’ market, or from your neighbor’s backyard hens, could contain Salmonella.”
Refrigeration also preserves egg quality. Learn more about the correlation between refrigeration and egg quality from a study by USDA Agricultural Research Service.
Another important way to address Salmonella concerns is through proper cooking. Eggs should be cooked until both the whites and yolks are firm. Casseroles and other dishes that contain eggs should be cooked to at least 160°F. If you like eggs with a runny yolk or are preparing a recipe requiring raw eggs, use pasteurized eggs, which have been heated to a temperature that kills bacteria. The Food and Drug Administration recommends pasteurized eggs for the elderly, the very young, or anyone with a compromised immune system.
Eggs are an important source of protein and other nutrients. Keeping eggs stored properly ensures that eggs remain an integral part of a healthy diet.