Everything About Eggs

Egg labels can be confusing. Discover what the words cage free, natural, or certified organic we find on many boxes of eggs at the grocery store really mean. Complete information about eggs and their nutritional value.

Everything you ever wanted to know about eggs

And Some Facts You Didn't...

Most of the time, when it comes to eggs, people don't pay attention to what they buy.

Other times, they pay too much attention to the egg itself, discarding perfectly edible eggs because they might be aesthetically displeasing.

In the following paragraphs, we will explore the egg, dispel myths, and explain what the words on an egg carton really mean.

The dates on the egg carton, if inspected by the USDA, must display a Julian date. If you start with January first as number 1, you end with December thirty first as 365, representing the consecutive days of a given year. Sometimes this numbering system is used on egg cartons to say when they are packed. Some will also carry the expiration date; which indicates the last date those eggs should be sold. With USDA inspected eggs, the expiration date cannot exceed thirty days. Fresh eggs, though, can be stored in a refrigerator for four to five weeks beyond the packed on date.

Grading classes are determined by interior and exterior quality, and given letters to denote this quality: AA, A, and B. The USDA provides the grading service for eggs in many packing plants. The official grade shield reflects it has been graded under federal USDA standards; it is not compulsory. Some packers, grade their eggs under state regulations which must meet, and usually exceed, federal standards.

The process for grading eggs, examines both the interior qualities, as well as being sorted by size or weight. Grade and size are not related. Between the grades of AA, A, and B, there is no difference to nutritive value Because the production and marketing methods used today move eggs so quickly from the laying house to market, rarely will you find grade B's in your local supermarket -B graded eggs are wholesome to eat, but not as visually pleasing as the higher grades- as they tend to go to bakeries and other food service operations.

The egg sizes, Jumbo, Extra Large, Large, Medium, Small and Peewee. Medium, Large and Extra Large are classified according to the minimum net weight expressed in ounces per dozen. There are a few factors that decide the size of an egg; the first, and most important being the age of the hen. The older she becomes, the bigger her eggs are. Secondly, it depends on the breed of a hen, as well as weight. If the hen is underweight, she will produce small eggs. Heat, stress, overcrowding, and poor nutrition are also factors in generating smaller eggs.

Careful flock management is important to an egg producer. The smallest shift in the egg weight can change what size the eggs will be classified under, and it will reflect in the pricing.

Most of U.S. egg producers comply with a voluntary program which routinely inspects factory and farms for cruel and inhumane practices. These eggs come with the label, United Egg Producers Certified.

Other labels you may see on the carton are:

Cage free - the hens are left to roam inside of a barn or warehouse, not in cages, but are not generally allowed to go outside.

Certified Humane - the same as cage free, but they follow certain regulations on how many birds to a barn or warehouse, number of nesting boxes and perches, and is a program by Humane Farm Animal Care.

Certified Organic - it means that the hens are cage free and required some outdoor time. They are feed organic, vegetarian diets; free of antibiotic and pesticides as required by the USDA's National Organic Program -Commercial laying hen rations never contain hormones.

Fertile - means that the hens have access to a rooster, and the eggs can be incubated and hatched. There are no known advantages to eating fertile eggs, and because of the cost of feeding the hens and roosters, you will end up paying more for the fertile eggs. They also do not keep as well as well as the non-fertile ones.

Free Range - this is another label you might see. There are no standards for an egg to be called free range, or free roaming. Most instances the free range hens are cage free in barns, and have access to the outdoors.

Because of seasonal conditions, there is no such thing as a true free range or free roaming chicken. The eggs labeled in this manner tend to be more expensive due to the higher production costs and lower volume. The nutrient contents of free range, or free roaming eggs are not affected. Though as a writer that raises her own layers, I can attest the taste is different, more flavorful than the store-bought eggs. Free range hens have more access to greens and insects to eat then those in barns.

Eggs from hens that are fed all vegetarian diets, and no recycled or processed food, are labeled as natural. This can be misleading because, by nature, hens eat small insects. The label natural also means that the eggs are produced without hormones, antibiotics or steroids. The same type of egg can also be labeled as Vegetarian-Fed.

There is debate over eggs that are labeled as Omega-3 enriched. They claim that these eggs are the same as the classic egg, except that they have a higher content of polyunsaturated fatty acid, a.k.a. omega-3. They are produced by altering the diet of the hens, feeding them a diet that contains between ten and twenty percent ground flaxseed which is higher in omega-3, and lower in saturated fatty acids then that of other grains. The debate rises from the claims that this type of egg is heart healthy. There has been no long term research into this.

Now let us take about freshness. There are many factors when it comes to the freshness of an egg. Under the ideal conditions a week old egg can be fresher than an egg only one day old. It isn't just the date that an egg is laid, but how it is handled that determine the freshness. Ideally an egg should be promptly gathered, washed and oiled within a few hours after being laid, and kept refrigerated at 40° F with a humidity of seventy to eighty percent. Most of the eggs that you buy at the local supermarket arrive within a few days of leaving the laying house. If handled properly, they will still be fresh when they reach your table.

If you have your own layers in your backyard, unless you are oiling them, they should not be washed prior to refrigeration. There is a myth about testing the freshness of an egg by placing it in salt water, as I said, this is only a myth and is not based in any facts. A controlled brine test is sometimes used to judge the thickness of a shell for hatching. As an egg ages, the whites will become thinner and the yolk will be flatter. These things do not have a significant effect on the nutritional quality or function in a recipe. Appearance can be affected when poached or fried; the older egg tends to not hold its form and spreads in the pan. But when dealing with boiled eggs, week old eggs will be easier to peel.

The shell accounts for nine to twelve percent of its total weight. It is the egg's first line of defense against contamination. The egg shell is made of ninety-four percent calcium carbonate and small amounts of magnesium as well as other organic matter, such as protein. The strength of a shell depends on the hen's diet. If not given enough calcium, or the hen is young, you get soft-shelled eggs. The shell has thousands of tiny pores, and as the egg ages, these tiny holes allow moisture and carbon dioxide to move out and allow air to move in to form the air cell. The shell is covered in a protective coating called cuticle. This coating helps preserve the egg preventing contamination of the contents. The color of the shell (white, brown or blue) does not affect the taste or nutritional values.

Albumen, a.k.a. the egg white, accounts for most of the eggs' liquid weight. It contains more than half the total protein, chlorine, potassium, sulfur, riboflavin and niacin of the egg. Depending on the diet of the hen, the yolk's color will be different shades of yellow. The yolk contains most of the iron, copper, manganese, phosphorus, iodine, and calcium, and the yolk of a large egg contains about 59 calories. All of the egg's vitamins are in the yolk (A, D, and E). An egg is one of the few natural foods that contain vitamin D. Double yolk eggs are produced mainly by young hens, and, occasionally, the younger hens can produce eggs with no yolk at all.

Sometimes you will find a blood spot on the yolk. This does not mean that the egg is fertilized. It is only a blood vessel on the yolk's surface that ruptured during the egg's formation. Producers use mass candling to try and weed out the yolks that have blood spots, but they cannot always catch them all. A blood spot can also indicate the egg's freshness, as the egg ages the yolk takes up water from the albumen, diluting the blood spot. They are fine to eat, but you can remove the blood spot with the tip of a butter knife if needed.

The chalaza is the white rope-like strands that anchor the yolk. They are not imperfections, nor to indicate the beginnings of an embryo. They do not interfere with cooking and do not need to be removed. It also reflects the freshness of an egg, the more predominant the chalaza, the fresher the egg.

The risk of getting a food borne illness from eggs is very low. Salmonella infection has been found inside a small number of eggs. Scientists estimate that, on average across the U.S., only one of every twenty thousand eggs might contain the bacteria. An average egg consumer might encounter a contaminated egg only once every eighty-four years.

Salmonella is found widely in nature and spreads easily. It is found in the intestinal tracts of animals, reptiles, insects as well as birds and humans. The egg itself may not be contaminated when you buy it, but can become so from various sources, such as your pets, other foods, you kitchen equipment as well as your hands. Most of all the reported salmonellosis outbreaks involving eggs have occurred in food service kitchens, caused by inadequate refrigeration, improper handling, and under cooking. The United States Department of Agriculture (USDA) and the Food and Drug Administration (FDA) are developing new national standards to reduce and eventually eliminate egg related salmonellosis.