Nov. 18, 2011 — -- In the wake of an ABC News "20/20" investigation into potentially unhealthy conditions at one of America's top egg producers, fast food giant McDonald's announced it would be finding eggs for its famous breakfast menu elsewhere.
Watch the full story on "20/20" tonight at 10 p.m. ET.
But how can you be sure the eggs you're picking up at the local supermarket are clean and safe to eat, no matter where they come from?
According to the Food and Drug Administration, an estimated 142,000 illnesses every year are caused by people eating eggs that are contaminated with salmonella. And though the FDA has regulations in place meant to keep the eggs clean before they hit your pan, the administration says consumers are their own best safeguard.
Whether the chicken that produced the eggs was infected with salmonella or the eggs were subjected to unsanitary conditions, the most effective way to be safe is simply to cook them, according to former FDA food safety chief David Acheson, and cook them well.
"What do I mean by cook them? Salmonella will be killed if you cook your eggs so that everything is hard," Acheson told ABC News. "The white is hard and the yolk is hard."
To be totally safe that means, according to Acheson, no runny yolks or eggs sunnyside up.
"If the yolk is runny or the white is runny, the salmonella -- if it's in there -- can survive," he said.
For any recipes that require eggs be undercooked, the FDA recommends using eggs that have been treated to destroy salmonella through pasteurization.
Before cooking, the FDA emphasizes that everything needs to be kept clean.
"Wash hands, utensils, equipment, and work surfaces with hot, soapy water before and after they come in contact with eggs and egg-containing foods," the FDA says on its website.
After cooking, the FDA says to serve immediately so bacteria doesn't get a chance to get back into the dish.
As far as storing eggs for long periods, you can freeze whole eggs, beat yolks and whites together, but eggs should not be frozen in their shells. If you want to refrigerate left-over eggs, make sure to use them within three or four days, the FDA says.
For more on egg safety, including an instructional video, visit the FDA website by clicking here.