While shopping at a farmers market I asked various vendors what the difference was between more expensive organic eggs and cheaper supermarket eggs available. Most agreed that the flavor of organic eggs is superior. One broke open a fresh egg and tossed it from one hand to the other to demonstrate the firmness of the yolk. But the vendors’ responses made me wonder if the average consumer knows the facts.
Egg color
• Shell color is determined by the breed of the hen that lays the egg. White eggs are most common. Brown eggs are more expensive because the hens that lay them are bigger and require more food.
• The shell color has no effect on the nutrition value of the egg.
• The fresher the egg, the cloudier the egg white. As the egg ages, the white becomes clearer and thinner.
• Egg yolk color is determined by what the chicken eats. Deep yellow yolks are typically from chickens that are fed yellow corn and alfalfa meal. Pale yellow yolks are from hens fed wheat or barley. Cage-free chickens that forage and eat a variety of grains lay eggs with a deep orange-yellow yolk.
Egg nutrition
• A large egg contains 70 calories, 6 grams of protein, and 5 grams of fat, of which 2 grams are saturated fat. The white contains most of the protein, and the yolk has all the fat.
• Eggs are excellent sources of nutrients including vitamin B12 and the antioxidant lutein, which is important for healthy eyes.
• Research on the effects of the 212 milligrams of cholesterol in a large egg has shown no association between eating one egg a day and heart disease for the healthy person. But remember to account for eggs in other products — cakes, cookies and pasta for example — if counting dietary cholesterol is important to your health.
• Omega-3-enhanced eggs contain substantially more heart-healthy DHA than regular eggs. These eggs come from hens fed a special diet.
• Organic and conventional eggs are equally nutritious.
Egg safety
• Eggs eaten raw or undercooked may cause serious illness from salmonella contamination. Bacteria can exist inside an uncracked, uncooked whole egg. Avoid eating raw cookie dough or making ice cream or Caesar salad dressing with raw eggs. Fully cooking eggs destroys the bacteria.
• Cook eggs until the yolk and the whites are firm. Cook egg custards used in eggnog, homemade ice cream and quiches to 160 degrees. Bake meringues at 350 degrees for 15 minutes on the lower rack.
• Substitute pasteurized eggs in recipes requiring raw eggs. No documented food-borne illness has ever been linked to the use of pasteurized eggs.
Storing eggs
• Store eggs in their original carton to prevent them from absorbing odors from other foods in the refrigerator.
• Avoid storing eggs in the door of the refrigerator. The air at the door is warmer.
• Leaving eggs unrefrigerated even for short periods of time diminishes freshness.
• Eggs retain freshness up to approximately one month after purchase.
• Raw egg whites will keep one week in the refrigerator and 12 months in the freezer. Egg yolks will keep three days in the refrigerator and 12 months in the freezer. Eggs frozen whole in their shell will crack, allowing bacteria to enter.
• Refrigerate hardcooked eggs unpeeled up to one week.
Egg labels
• Organic eggs come from cage-free hens that can roam freely outside. They are fed organic grain and no antibiotics. This is the only label that is backed by USDA standards and regulations.
• Cage-free hens are not confined to cages but may not have access to the outdoors. Their environment and eggs are not audited by a third party.
• There is no consensus of a definition or enforced or regulated standards for these terms: free range, natural, no pesticides or no antibiotics.
Registered dietitian Shirley Perryman is an Extension specialist with the Department of Food Science and Human Nutrition at Colorado State University.
