How Does Salmonella Infect Eggs?
Bacteria can be on the outside of a shell egg. That's because the egg exits the hen's body through the same passageway as feces is excreted. That's why eggs are washed and sanitized at the processing plant. 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. SE doesn't make the hen sick. It is also possible for eggs to become infected by Salmonella Enteritidis fecal contamination through the pores of the shells after they're laid.
What Part Carries Bacteria?
Researchers say that, if present, the SE is usually in the yolk or "yellow." However, they can't rule out the bacteria being in egg whites. So everyone is advised against eating raw or undercooked egg yolks and whites or products containing raw or undercooked eggs.
What Safe Handling Instructions are on Egg Cartons?
All packages of raw, shell
eggs not treated to destroy Salmonella
must carry the following safe handling
Who is "At Risk" for Eating Raw or Undercooked Eggs?
People with health problems, the very young, senior citizens, and pregnant women (the risk is to the unborn child) are particularly vulnerable to SE infections. A chronic illness weakens the immune system, making the person vulnerable to foodborne illnesses.
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. However, in-shell pasteurized eggs may be used safely without cooking.
Who is Working on Eliminating the Salmonella in Eggs?Federal and state governments, the egg industry, and the scientific community are working together to solve the problem. Involved government agencies include: USDA's Food Safety and Inspection Service (FSIS), Agricultural Marketing Service (AMS), and the Animal and Plant Health Inspection Service (APHIS); the U.S. Food and Drug Administration (FDA); and State departments of agriculture.
Government agencies have implemented an Egg Safety Action Plan to eliminate Salmonella Enteritidis illnesses due to eggs. The Action Plan identifies the systems and practices that must be carried out in order to meet the goal of eliminating SE illnesses associated with the consumption of eggs by 2010. The interim goal of the Egg Safety Action Plan is a 50 percent reduction in egg-associated SE illnesses by 2005.
What Government Agencies are Responsible for the Safety of Shell Eggs?Many government agencies cooperate to ensure the safety of shell eggs from farm to table.
USDA Agencies: Agricultural Marketing Service (AMS)
Animal and Plant Health Inspection Service (APHIS)
Food Safety and Inspection Service (FSIS)
Agricultural Research Service (ARS)
National Agricultural Statistics Service (NASS)
State Agriculture Departments
State and Local Health Departments
What is Candling?Candling is the process of using light to help determine the quality of an egg. Automated mass-scanning equipment is used by most egg packers to detect eggs with cracked shells and interior defects. During candling, eggs travel along a conveyor belt and pass over a light source where the defects become visible. Defective eggs are removed. Hand candling - holding a shell egg directly in front of a light source - is done to spot check and determine accuracy in grading.
How Are Eggs Transported Safely to Stores?The U.S. Department of Commerce's 1990 Sanitary Food Transportation Act requires that vehicles be dedicated to transporting food only. On August 27, 1999, FSIS made effective a new rule requiring:
What Is Included Under the Egg Products Inspection Act?The term "egg products" refers to eggs that have been removed from their shells for processing at facilities called "breaker plants." The safety of these products is the responsibility of FSIS. Basic egg products include whole eggs, whites, yolks, and various blends -- with or without non-egg ingredients -- that are processed and pasteurized. They may be available in liquid, frozen, and dried forms. Most are not available in supermarkets, but are used in restaurants, hospitals, and other foodservice establishments as well as by bakers, noodle makers, and other food manufacturers.
Egg products are pasteurized. The 1970 Egg Products Inspection Act (EPIA) 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.
Can Shell Eggs Be Pasteurized?Shell eggs can be pasteurized by a processor if FDA approves the process. Pasteurized shell eggs are available in some parts of the country, but are not yet available nationwide. Also, the equipment necessary to pasteurize eggs isn't available for home use, and it's not possible to pasteurize eggs in the home.
Are Powdered Egg Whites Pasteurized?Yes. Egg white powder is dried egg white (pure albumen). It can be reconstituted by mixing the powder with water. The reconstituted powder whips like fresh egg white and, because it is pasteurized, can be used safely without cooking or baking it. The product is usually sold along with supplies for cake baking and decorating.
What Points Should You Consider When Buying Eggs?Always purchase eggs from a refrigerated case. Choose eggs with clean, uncracked shells. Don't buy out-of-date eggs. Look for the USDA grade shield or mark. Graded eggs must meet standards for quality and size. Choose the size most useful and economical for you.
Is Grading of Eggs Mandatory?USDA's grading service is voluntary; egg packers who request it, pay for it. The USDA grade shield on the carton means that the eggs were graded for quality and checked for weight (size) under the supervision of a trained USDA grader. Compliance with quality standards, grades, and weights is monitored by USDA. 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.
What Are Egg Grades?There are three consumer grades for eggs: U.S. Grade AA, A, and B. The grade is determined by the interior quality of the egg and the appearance and condition of the egg shell. Eggs of any quality grade may differ in weight (size).
Sizing of EggsSize tells you the minimum required net weight per dozen eggs. It does not refer to the dimensions of an egg or how big it looks. While some eggs in the carton may look slightly larger or smaller than the rest, it is the total weight of the dozen eggs that puts them in one of the following classes:
Dating of CartonsMany eggs reach stores only a few days after the hen lays them. Egg cartons with the USDA grade shield on them must display the "pack date" (the day that the eggs were washed, graded, and placed in the carton). The number is a three-digit code that represents the consecutive day of the year (the "Julian Date") starting with January 1 as 001 and ending with December 31 as 365.
Always purchase eggs before the "Sell-By" or "EXP" (expiration) date on the carton. After the eggs reach home, they may be refrigerated 3 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.
Why Should Eggs Be Refrigerated?Temperature fluctuation is critical to safety. With the concern about Salmonella, eggs gathered from laying hens should be refrigerated as soon as possible. After eggs are refrigerated, they need to stay that way. A cold egg left out at room temperature can sweat, facilitating the growth of bacteria. Refrigerated eggs should not be left out more than 2 hours.
Should You Wash Eggs?No. When the egg is laid, a protective coating is put on the outside by the hen. At the plant, government regulations require that USDA-graded eggs be carefully washed and sanitized using special detergent. Then the egg is coated with a tasteless, natural mineral oil to protect it.
Why Do Hard-Cooked Eggs Spoil Faster than Fresh Eggs?When shell eggs are hard cooked, the protective coating is washed away, leaving bare the pores in the shell for bacteria to enter and contaminate it. Hard-cooked eggs should be refrigerated within 2 hours of cooking and used within a week.
Safe Storage in StoresAt the store, choose Grade A or AA eggs with clean, uncracked shells. Make sure they've been refrigerated in the store. Any bacteria present in an egg can multiply quickly at room temperature. When purchasing egg products or substitutes, look for containers that are tightly sealed.
Bringing Eggs Home from the StoreTake eggs straight home and store them immediately in the refrigerator set at 40 F or below. Keep them in their carton and place them in the coldest part of the refrigerator, not in the door. Don't wash eggs. That could remove the protective mineral oil coating and increase the potential for bacteria on the shell to enter the egg.
Is It Safe to Use Eggs That Have Cracks?Bacteria can enter eggs through cracks in the shell. Never purchase cracked eggs. However, if eggs crack on the way home from the store, break them into a clean container, cover it tightly, keep refrigerated, and use within 2 days. If eggs crack during hard cooking, they are safe.
How Are Eggs Handled Safely?Proper refrigeration, cooking, and handling should prevent most egg-safety problems. Persons can enjoy eggs and dishes containing eggs if these safe handling guidelines are followed.
Are Easter Eggs Safe?Sometimes eggs are decorated, used as decorations, and hunted at Easter. Here are some safety tips for Easter eggs.
Does the Color of the Shell Affect the Egg's Nutrients?No. The breed of the hen determines the color of her eggs.
Araucuna chickens in South America lay eggs that range in color from medium blue to medium green. Nutrition claims that araucuna eggs contain less cholesterol than other eggs haven't been proven.
Are Fertilized Eggs More Nutritious?No. There is no benefit in eating fertilized eggs. There is no nutritional difference in fertilized eggs and infertile eggs. Most eggs sold today are infertile; roosters are not housed with the laying hens. If the eggs are fertile and cell development is detected during the candling process, they are removed from commerce.
Per Capita ConsumptionEgg consumption in America was on a 40-year downward slide until the 1990's. Then eggs became increasingly popular. The following figures are from USDA's Economic Research Service.
Is the Appearance of Eggs Related to Food Safety?Sometimes, but not usually. Variation in egg color is due to many factors.
How Do Time and Refrigeration Affect Egg Quality?The egg, as laid at 105 F, normally has no air cell. It forms as the egg cools, usually in the large end of the egg, and develops between the two shell membranes. The air cell is formed as a result of the different rates of contraction between the shell and its contents.
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 cord-like strands of egg white that anchor the yolk in 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.
What Does It Mean When an Egg Floats in Water?An egg can float in water when its air cell has enlarged sufficiently to keep it buoyant. This means the egg is old, but it may be perfectly safe to use. Crack the egg into a bowl and examine it for an off-odor or unusable appearance before deciding to use or discard it. A spoiled egg will have an unpleasant odor when you break open the shell, either when raw or cooked.
Safe Cooking MethodsMany cooking methods can be used to cook eggs safely including poaching, hard cooking, scrambling, frying and baking. However, eggs must be cooked thoroughly until yolks are firm. Scrambled eggs should not be runny. Casseroles and other dishes containing eggs should be cooked to 160 F. Use a food thermometer to be sure.
Use Safe Egg RecipesEgg mixtures are safe if they reach 160 F, so homemade ice cream and eggnog can be made safely from a cooked egg-milk mixture. Heat it gently and use a food thermometer.
What Makes Hard-Cooked Eggs Hard to Peel?The fresher the egg, the more difficult it is to peel after hard cooking. That's because the air cell, found at the large end of the shell between the shell membranes, increases in size the longer the raw egg is stored. As the contents of the egg contracts and the air cell enlarges, the shell becomes easier to peel. For this reason, older eggs make better candidates for hard cooking.
What Are Thousand-Year-Old Eggs?These Chinese eggs are not really 1,000 years old, but are somewhere between a month and several years old. The egg is not retained in its original state, but rather converted into an entirely different food, probably by bacterial action. They are exempt from inspection and grading. The following are several types of thousand-year-old Chinese eggs.
"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.
Do Pickled Eggs Keep a Long Time?Pickled eggs are hard-cooked eggs marinated in vinegar and pickling spices, spicy cider, or juice from pickles or pickled beets. Studies done at the American Egg Board substantiate that unopened containers of brined eggs -- marinated, hard-cooked eggs -- keep for several months on the shelf. After opening, keep refrigerated.
EGG STORAGE CHART
For additional food safety information about meat, poultry, or egg products, call the toll-free USDA Meat and Poultry Hotline at 1-888-MPHotline (1-888-674-6854); for the hearing-impaired (TTY) 1-800-256-7072. The Hotline is staffed by food safety experts weekdays from 10 a.m. to 4 p.m. Eastern time. Food safety recordings can be heard 24 hours a day using a touch-tone phone.