First, find out how fresh the eggs really are. The freshest ones are the eggs that sink and lie flat on their sides when submerged in cool water. These eggs can be used for any dish. By the time the egg is a week old, the air pocket inside, near the broad end, has expanded so that the broad end tilts up as the egg is submerged in cool water. The yolk and the white inside have begun to separate; these eggs are easier to peel when hard-cooked. A week or two later, the egg's air pocket has expanded enough to cause the broad end of the egg to point straight up when you put the egg in water. By now the egg is runny and should be used in sauces where it doesn't matter if it isn't picture-perfect. After four weeks, the egg will float. Throw it away.
Eggs are easily contaminated with Salmonella microorganisms that can slip through an intact shell. NEVER EAT OR SERVE A DISH OR BEVERAGE MADE WITH RAW FRESH EGGS. SALMONELLA IS DESTROYED BY COOKING EGGS TO AN INTERNAL TEMPERATURE OF 145