First, the extra-safe rules from the people who cover all the bases: Raw eggs should be refrigerated at 40 degrees Fahrenheit or lower when you’re not using them, says Elisa Maloberti, a spokesperson for the American Egg Board. “[Eggs] should not be left at room temperature for more than two hours, including the time used to prepare and serve them. Allow no more than 30 minutes to one hour when it’s 85 degrees Fahrenheit or hotter [out].”

“The main safety concern with shell eggs is Salmonella enteritidis [SE] bacteria inside the egg,” says Hilary Shallo Thesmar, PhD, director of the Egg Safety Center in Washington DC. “Occasionally, hens become infected with SE and deposit the bacteria in the egg as it is being formed in the reproductive tract. Eggs look, taste, and smell completely normal.” The Egg Safety Center says that 1 egg in 20,000 may contain salmonella, which is a contamination rate of 0.005 percent. Storing eggs below 40 degrees Fahrenheit “keeps bacteria from growing to large enough numbers to cause illness,” says the American Egg Board’s Maloberti.

But if you’re buying local eggs at a farmers’ market, you may have more leeway. The organic egg farmers we spoke with said it depends on the egg. Alvin Schlangen, owner and manager of Schlangen Family Farm in Minnesota, says that he would not recommend leaving out “just any old egg” and that following the cold storage guideline is “vitally important if your egg quality is lacking.” But he suggests relying more on common sense than federal regulations: “Know your farmer and know how he manages his flock of hens. If your source hens are pastured and on chemical-free feed, you’ll have no concerns about leaving cartoned eggs out at room temperature for a few days. If you plan to keep them longer than that, I’d chill them.”

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