Bacteria can be inside an uncracked, whole egg. Contamination of eggs may be due to bacteria within the hen’s ovary or oviduct before the shell forms around the yolk and white. Salmonellae bacteria don’t make the hen sick. It is also possible for eggs to become infected by fecal contamination through the pores of the shells after they’re laid.

No one should eat foods containing raw eggs. This includes "health food" milk shakes made with raw eggs, Caesar salad, Hollandaise sauce, and any other foods like homemade mayonnaise, ice cream, or eggnog made from recipes in which the egg ingredients are not cooked.

USDA Agencies:

Agricultural Marketing Service (AMS)

• AMS administers a voluntary egg-quality grading program for shell eggs paid for by processing plants.
• AMS also is responsible for the shell egg surveillance program to assure that eggs in the marketplace are as good as or better than U.S. Consumer Grade B. AMS visits shell egg handlers and hatcheries four times each year to ensure conformance with these requirements.
• The USDA grade mark on egg cartons means the plant processed the eggs following USDA’s sanitation and good manufacturing processes.
• On April 27, 1998, AMS announced a prohibition on the repackaging of eggs packed under its voluntary grading program.

Animal and Plant Health Inspection Service (APHIS)

• APHIS conducts activities to reduce the risk of disease in flocks of laying hens.
• APHIS administers the voluntary National Poultry Improvement Plan (NPIP), which certifies that poultry breeding stock and hatcheries are free from certain diseases. Participation is necessary for producers that ship interstate or internationally.
• APHIS' National Animal Health Monitoring System is currently conducting a nationwide survey of the egg industry whose purpose is to estimate the national prevalence of Salmonella enteritidis in layer flocks.

Food Safety and Inspection Service (FSIS)

• FSIS is responsible for imported shell eggs from all countries. Due to AMS' expertise in these areas, AMS carries out these tasks on behalf of FSIS.
• USDA also strives to educate consumers about the safe handling of eggs. FSIS has developed numerous publications on egg safety and uses a variety of networks (such as the USDA Meat and Poultry Hotline and USDA cooperative extension agents) to get this information to consumers.

Agricultural Research Service (ARS)

• USDA also carries out food safety research through ARS and through a program administered by USDA's Cooperative State Research, Education & Extension Service (CSREES). Subjects include studying how Salmonella adheres to chicken cells, and developing an oral vaccine against Salmonella enteritidis.

National Agricultural Statistics Service (NASS)

• USDA collects processing and distribution information for the economic analysis of the egg products industry through NASS.

FSIS/FDA Cooperation

• FSIS and the Food and Drug Administration (FDA) share authority for egg safety and are working together toward solving the problem of Salmonella enteritidis in eggs.
• FSIS and FDA are working to strengthen the Food Code and to encourage its adoption by States and local jurisdictions.

State Agriculture Departments:

• State agriculture departments monitor compliance with official U.S. standards, grades, and weight classes by egg packers not using the USDA/AMS shell egg grading service.

State and Local Health Departments:

• State and local health departments monitor compliance with state and local health department requirements by food retail and foodservice establishments.

• shell eggs packed for consumers be stored and transported under refrigeration at an ambient (surrounding) air temperature not to exceed 45 °F;
• all packed shell eggs be labeled to state that refrigeration is required; and
• any shell eggs imported into the United States, packed for consumer use, include a certification that they have been stored and transported at an ambient temperature of no greater than 45 °F.

Egg products are pasteurized. The 1970 Egg Products Inspection Act requires that all egg products distributed for consumption be pasteurized. They are rapidly heated and held at a minimum required temperature for a specified time. This destroys Salmonella, but it does not cook the eggs or affect their color, flavor, nutritional value, or use. Dried eggs are pasteurized by heating in the dried form.

While inspected pasteurized egg products are used to make freeze-dried egg products, imitation egg products, and egg substitutes, these products are not covered under the EPIA and are under FDA jurisdiction. No-cholesterol egg substitutes consist of egg whites, artificial color, and other non-egg additives. Direct questions about egg substitutes to the manufacturer or to the FDA.

State agencies monitor compliance for egg packers who do not use the USDA grading service. These cartons will bear a term such as "Grade A" on their cartons without the USDA shield.

U.S. Grade AA eggs have whites that are thick and firm; yolks that are high, round, and practically free from defects; and clean, unbroken shells. Grade AA and Grade A eggs are best for frying and poaching where appearance is important, and for any other purpose.

U.S. Grade A eggs have characteristics of Grade AA eggs except that the whites are "reasonably" firm. This is the quality most often sold in stores.

U.S. Grade B eggs have whites that may be thinner and yolks that may be wider and flatter than eggs of higher grades. The shells must be unbroken, but may show slight stains. This quality is seldom found in retail stores because they are usually used to make liquid, frozen, and dried egg products.

Always purchase eggs before the "sell-by" or "EXP" (expiration) date on the carton. After the eggs reach home, they may be refrigerated 4 to 5 weeks from the day they are placed in the refrigerator. The "sell-by" date will usually expire during that length of time, but the eggs are perfectly safe to use. This date is not federally required, but may be State required.

• Wash hands, utensils, equipment, and work areas with hot, soapy water before and after contact with eggs.
• Don’t keep eggs out of the refrigerator more than 2 hours.
• Raw eggs and other ingredients, combined according to recipe directions, should be cooked immediately or refrigerated and cooked within 24 hours.
• Serve cooked eggs and dishes containing eggs immediately after cooking, or place in shallow containers for quick cooling and refrigerate at once for later use. Use within 3 to 4 days.

Dyeing eggs: After hard cooking eggs, dye them and return them to the refrigerator within 2 hours. If eggs are to be eaten, use a food-safe coloring. As with all foods, persons dyeing the eggs should wash their hands before handling the eggs.

Decorations: One Easter bread recipe is decorated with dyed, cooked eggs in the braided bread. Because the bread is kept at room temperature, these eggs should be considered a decoration only and not eaten.

Blowing out eggshells: Because some raw eggs may contain Salmonella, you must use caution when blowing out the contents to hollow out the shell for decorating, such as for Ukranian Easter eggs. Use only eggs that have been kept refrigerated and are uncracked. To destroy bacteria that may be present on the surface of the egg, wash the egg in hot water and then rinse in a solution of 1 teaspoon chlorine bleach per half cup of water. After blowing out the egg, refrigerate the contents and use within 2 to 4 days; cook thoroughly before eating.

Hunting Eggs: Hard-cooked eggs for an egg hunt must be prepared with care to prevent cracking the shells. If the shells crack, bacteria could contaminate the inside. Eggs should be hidden in places that are protected from dirt, pets, and other sources of bacteria. The total time for hiding and hunting eggs should not exceed 2 hours. The "found" eggs must be re-refrigerated until eaten.

Today’s large egg contains 70 calories, 5 grams of fat, and 6 grams of protein. The egg is a good source of complete protein, vitamins A and B-12, riboflavin, folacin, iron, zinc, and phosphorus.

Nutrition claims that araucuna eggs contain less cholesterol than other eggs haven’t been proven.

Blood spots are caused by a rupture of one or more small blood vessels in the yolk at the time of ovulation. It does not indicate the egg is unsafe.

A cloudy white (albumen) is a sign the egg is very fresh. A clear egg white is an indication the egg is aging.

Pink or iridescent egg white (albumen) indicates spoilage due to Pseudomonas bacteria. Some of these microorganisms – which produce a greenish, fluorescent, water-soluble pigment – are harmful to humans.

The color of yolk varies in shades of yellow depending upon the diet of the hen. If she eats plenty of yellow-orange plant pigments, such as from marigold petals and yellow corn, the yolk will be a darker yellow than if she eats a colorless diet such as white cornmeal. Artificial color additives are not permitted in eggs.

A green ring on a hard-cooked yolk is a result of overcooking, and is caused by sulfur and iron compounds in the egg reacting on the yolk’s surface. The green color can also be caused by a high amount of iron in the cooking water. Scrambled eggs cooked at too high a temperature or held on a steam table too long can also develop a greenish cast. The green color is safe to consume.

Over time, the white and yolk of an egg lose quality. The yolk absorbs water from the white. Moisture and carbon dioxide in the white evaporate through the pores, allowing more air to penetrate the shell, and the air cell becomes larger. If broken open, the egg’s contents would cover a wider area. The white would be thinner, losing some of its thickening and leavening powers. The yolk would be flatter, larger and more easily broken. The chalazae (kah-LAY-zuh), the twisted cork-like strands of egg white that anchor the yolk to the center of the white, would be less prominent and weaker, allowing the yolk to move off center. Refrigeration slows the loss of quality over time.

• Fried eggs -- cook 2 to 3 minutes on each side, 4 minutes in a covered pan;
• Scrambled eggs -- cook until firm throughout;
• Poached eggs -- 5 minutes over boiling water;
• Soft-cooked eggs -- 7 minutes in the shell in boiling water.

• Dry meringue shells are safe. So are divinity candy and 7-minute frosting, made by combining hot sugar syrup with beaten egg whites. Avoid icing recipes using uncooked eggs or egg whites.
• Meringue-topped pies should be safe if baked at 350 °F for about 15 minutes. Chiffon pies and fruit whips made with raw, beaten egg whites cannot be guaranteed to be safe. Instead, substitute pasteurized dried egg whites, whipped cream, or a whipped topping.
• To make a recipe safe that specifies using eggs that aren’t cooked, heat the eggs in a liquid from the recipe over low heat, stirring constantly, until the mixture reaches 160 °F. Then combine it with the other ingredients and complete the recipe.
• To determine doneness in egg dishes such as quiche and casseroles, insert a knife in the center. It should come out clean and the mixture should reach 160 °F on a food thermometer.

"Hulidan" results when eggs are individually coated with a mixture of salt and wet clay or ashes for a month. This process darkens and partially solidifies the yolks, and gives the eggs a salty taste.

"Dsaudan" eggs are packed in cooked rice and salt for at least 6 months. During this time, the shell softens, the membranes thicken, and the egg contents coagulate. The flavor is wine-like.

"Pidan," a great delicacy, is made by covering eggs with lime, salt, wood ashes, and a tea infusion for 5 months or more. The egg yolks become greenish gray and the albumen turns into a coffee-brown jelly. Pidan smell ammonia-like and taste like lime.