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PARTS OF THE EGG Germinal Disk

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2 PARTS OF THE EGG Germinal Disk
contains more than half the egg's total protein, niacin, riboflavin, chlorine, magnesium, potassium, sodium and sulfur. The albumen consists of 4 alternating layers of thick and thin consistencies. From •Composed of calcium Carbonate •Color determined by breed of hen and does not effect flavor, nutritive value or shell thickness •Color varies with feed of the hen •Major source of vitamin A; Iron; Fat; and Protein Germinal Disk •Clear membrane that holds the egg yolk •Twisted cord-like strands of egg white •Anchors yolk in the center of the egg •A prominent chalazae indicates freshness •pocket of air formed at large end of the egg •increases as egg ages •two membranes-inner and outer- surround the albumen •provides a protective barrier against bacterial penetration •air cell forms between these two membranes •Nearest to the shell •Spreads around the thick white of high quality eggs •Major source of riboflavin and protein •Stands higher and spreads less than thin egg white in higher grade eggs •Thin becomes indistinguishable from thin white in lower grade eggs Air Cell
The empty space between the white and shell at the large end of the egg.When an egg is first laid, it is warm. As it cools, the contents contract and the inner shell membrane separates from the outer shell membrane to form the air cell.The candler uses the size of the air cell as one basis for determining grade. In Grade AA eggs, the air cell may not exceed 1/8-inch in depth and is about the size of a dime. The air cell of Grade A eggs may exceed 3/16-inch in depth. For Grade B eggs, there is no limit on air cell size.As the egg ages, moisture and carbon dioxide leave through the pores of the shell, air enters to replace them and the air cell becomes larger.Although the air cell usually forms in the large end of the egg, it occasionally moves freely toward the uppermost point of the egg as the egg is rotated. It is then called a free or floating air cell. If the main air cell ruptures, resulting in one or more small separate air bubbles floating beneath the main air cell, it is known as a bubbly air cell.You can see the air cell in the flattened end of a peeled, hard-cooked egg. Albumen
Also known as egg white. Albumen accounts for most of an egg's liquid weight, about 67%. It the yolk outward, they are designated as the inner thick or chalaziferous white, the inner thin white, the outer thick white and the outer thin white. Egg white tends to thin out as an egg ages because its protein changes in character. That's why fresh eggs sit up tall and firm in the pan while older ones tend to spread out.Albumen is more opalescent than truly white. The cloudy appearance comes from carbon dioxide. As the egg ages, carbon dioxide escapes, so the albumen of older eggs is more transparent than that of fresher eggs.When egg albumen is beaten vigorously, it foams and increases in volume 6 to 8 times. Egg foams are essential for making souffles, meringues, puffy omelets, and angel food and sponge cakes. Chalaza
 Ropey strands of egg white which anchor the yolk in place in the center of the thick white. They are neither imperfections nor beginning embryos.The more prominent the chalazae, the fresher the egg. Chalazae do not interfere with the cooking or beating of the white and need not be removed, although some cooks like to strain them from stirred custard. Germinal Disc The entrance of the latebra, the channel leading to the center of the yolk. The germinal disc is barely noticeable as a slight depression on the surface of the yolk. When the egg is fertilized, sperm enter by way of the germinal disc, travel to the center and a chick embryo starts to form. Shell The egg's outer covering, accounting for about 9 to l2% of its total weight depending on egg size. The shell is the egg's first line of defense against bacterial contamination.The shell is largely composed of calcium carbonate (about 94%) with small amounts of magnesium carbonate, calcium phosphate and other organic matter including protein.Shell strength is greatly influenced by the minerals and vitamins in the hen's diet, particularly calcium, phosphorus, manganese and Vitamin D. If the diet is deficient in calcium, for instance, the hen will produce a thin or soft-shelled egg or possibly an egg with no shell at all. Occasionally an egg may be prematurely expelled from the uterus due to injury or excitement. In this case, the shell has not had time to be completely formed. Shell thickness is also related to egg size which, in turn, is related to the hen's age. As the hen ages, egg size increases. The same amount of shell material which covers a smaller egg must be "stretched" to cover a larger one, hence the shell is thinner.Seven to 17 thousand tiny pores are distributed over the shell surface, a greater number at the large end. As the egg ages, these tiny holes permit moisture and carbon dioxide to move out and air to move in to form the air cell. The shell is covered with a protective coating called the cuticle or bloom. By blocking the pores, the cuticle helps to preserve freshness and prevent microbial contamination of the contents.Uses for eggshells vary from the thrifty (compost) to the creative Yolk
The yolk or yellow portion makes up about 33% of the liquid weight of the egg. It contains all of the fat in the egg and a little less than half of the protein.With the exception of riboflavin and niacin, the yolk contains a higher proportion of the egg's vitamins than the white. All of the egg's vitamins A, D and E are in the yolk. Egg yolks are one of the few foods naturally containing vitamin D.The yolk also contains more phosphorus, manganese, iron, iodine, copper, and calcium than the white, and it contains all of the zinc. The yolk of a Large egg contains about 59 calories.Double-yolked eggs are often produced by young hens whose egg production cycles are not yet completely synchronized. They're often produced, too, by hens who are old enough to produce Extra Large eggs. Genetics is a factor, also. Occasionally a hen will produce double-yolked eggs throughout her egg-laying career. It is rare, but not unusual, for a young hen to produce an egg with no yolk at all.In fertilized eggs, the yolk is the site of embryo formation.It is the yolk which is responsible for the egg's emulsifying properties.

3 EGG SIZES peewee small medium large Extra large Jumbo
15 ounces per dozen small medium large Extra large Jumbo Select by Weight (Size) (U.S. Weight Class) Size 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. Eggs of any weight (size) class may differ in quality. Most published recipes are based on large-size eggs. Size or weight class Minimum net weightper dozen Jumbo 30 ounces Extra Large 27 ounces Large 24 ounces Medium 21 ouncesSmall 18 ounces Peewee 15 ounces Sizes ム Size is determined by the following USDA minimum egg weights expressed in ounces per dozen eggs:

 SizeOunces per Dozen Extra Large27ハ Large24ハ Medium21ハ Small18ハ Peewee15

4 Candling . 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.

5 Quality and freshness Grade A Grade AA Select by U.S. Grade (Quality)
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). 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. U.S. Grade A eggs have whites that are reasonably firm; yolks that are high, round, and practically free from defects; and clean, unbroken shells. 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 the higher grades; the shells must be unbroken, but may show slight stains. This quality is seldom found in retail stores. U.S. Grade AA and A eggs are good for all purposes, but especially for poaching and frying where appearance is important. U.S. Grade B eggs, if available, are fine for general cooking and baking. Grade Shields Marks of Quality 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. Grade A Grade AA

6 FRESHNESS DATING Dating of Cartons
Many 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.

7 EGG COLOR Color Egg shell and yolk color may vary.
Color has no relationship to egg quality, flavor, nutritive value, cooking characteristics or shell thickness. As far as hue, the difference lies in the breed of chicken. In general, white chickens lay white eggs, brown chickens lay brown eggs, and blue eggs come from a South American breed called Araucana. When it comes to taste and nutrition, however, there is no difference. Color is not an indicator of quality. Yet preferences persist, perhaps due to misinformation, tradition, or aesthetic attraction. According to poultry farming publications of the 1910s and 20s, there existed a strong geographic divide; New Yorkers and San Franciscans were said to prefer white eggs, while Bostonians insisted upon brown. Even today, many consumers expect brown eggs to be more "natural." Brown eggs also tend to be more expensive, as the hens that lay white eggs are smaller, eat less, and are therefore preferred by commercial producers.

8 Handling eggs safely Safe Handling
Wash hands, utensils, equipment, and work areas with hot, soapy water before and after they come in contact with eggs and egg-containing foods. Remove only the number of eggs needed from the carton and return the carton to the refrigerator. Cook eggs until the white is completely firm and the yolk begins to thicken but is not hard. Scrambled eggs should be cooked until no visible liquid remains. Fried eggs should be cooked on both sides or in a covered pan. Take care when preparing egg-containing foods that are not cooked or are only lightly cooked before serving, such as ice cream, eggnog, mayonnaise, Caesar salad, hollandaise sauce, or béarnaise sauce. Only use recipes that start with a stirred egg custard base that is first cooked to 160 。F. If a recipe calls for adding raw eggs to a previously cooked dish, the dish must be cooked further until it reaches 160 。F. When preparing any recipe that contains eggs, resist the temptation to taste-test the mixture during preparation. Egg-containing foods should be thoroughly cooked before eating. When preparing and serving eggs and egg-rich foods, keep them out of the refrigerator no more than 2 hours total, not including cooking time. If hot egg-rich foods are not going to be served immediately after cooking, put the hot foods into shallow containers and refrigerate at once so they will cool quickly. SAFE HANDLING INSTRUCTIONS: To prevent illness from bacteria: Keep eggs refrigerated, cook eggs until yolks are firm, and cook foods containing eggs thoroughly. 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 food borne 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. Fresh eggs must be handled carefully. Even eggs with clean, uncracked shells may occasionally contain bacteria called Salmonella that can cause an intestinal infection. The most effective way to prevent egg-related illness is by knowing how to buy, store, handle and cook eggs—or foods that contain them—safely. That is why the U.S. Food and Drug Administration (FDA) requires all cartons of shell eggs that have not been treated to destroy Salmonella must carry the following safe handling statement: Eggs that have been treated to destroy Salmonella—by in-shell pasteurization, for example—are not required to carry safe handling instructions. Serve Safely Bacteria can multiply in temperatures from 40°F (5°C) to 140°F (60°C), so it's very important to serve foods safely. * Serve cooked eggs and egg-containing foods immediately after cooking. * For buffet-style serving, hot egg dishes should be kept hot, and cold egg dishes kept cold. * Eggs and egg dishes, such as quiches or soufflés, may be refrigerated for serving later but should be thoroughly reheated to 165°F (74°C) before serving. Chill Properly * Cooked eggs, including hard-boiled eggs, and egg-containing foods should not sit out for more than 2 hours. Within 2 hours either reheat or refrigerate. * Use hard-cooked eggs (in the shell or peeled) within 1 week after cooking * Use frozen eggs within one year. Eggs should not be frozen in their shells. To freeze whole eggs, beat yolks and whites together. Egg whites can also be frozen by themselves. * Refrigerate leftover cooked egg dishes and use within 3-4 days. When refrigerating a large amount of a hot egg-containing leftover, divide it into several shallow containers so it will cool quickly. On the Road * Cooked eggs for a picnic should be packed in an insulated cooler with enough ice or frozen gel packs to keep them cold. * Don't put the cooler in the trunk—carry it in the air-conditioned passenger compartment of the car. * If taking cooked eggs to work or school, pack them with a small frozen gel pack or a frozen juice box. Handling eggs safely

9 NUTRITION Protein Vitamin A Fats Omega 3 Cholesterol riboflavin
Nutritional value Eggs provide a significant amount of protein to one's diet, as well as various nutrients. Chicken eggs are the most commonly eaten eggs, and are highly nutritious. They supply a large amount of complete, high-quality[3] protein (which contains all essential amino acids for humans), and provide significant amounts of several vitamins and minerals, including vitamin A, riboflavin, folic acid, vitamin B6, vitamin B12, choline, iron, calcium, phosphorus and potassium. They are also one of the least expensive single-food sources of complete protein. One large chicken egg contains approximately 7 grams of protein.3 egg yolks in a glassAll of the egg's vitamin A, D and E is in the yolk. The egg is one of the few foods which naturally contain vitamin D (although this nutrient is naturally produced in humans when their skin is exposed to sunlight). A large egg yolk contains approximately 60 calories (250 kilojoules); the egg white contains about 15 calories (60 kilojoules). A large yolk contains more than two-thirds of the recommended daily intake of 300 mg of cholesterol (although one study shows that your body does not absorb much cholesterol from eggs[4]). The yolk makes up about 33% of the liquid weight of the egg. It contains all of the fat in the egg and slightly less than half of the protein. It also contains all of the choline, and one yolk contains approximately half of the recommended daily intake. Choline is an important nutrient for development of the brain, and is said to be important for pregnant and nursing women to ensure healthy fetal brain development [5].Recently, chicken eggs that are especially high in Omega 3 fatty acids have come on the market. These eggs are made by feeding laying hens a diet containing polyunsaturated fats and kelp meal. Two brands available in the UK are "Columbus Eggs"[6] and "The Hearty Egg"[7]. Nutrition information on the packaging is different for each of the brands Cholesterol and fat Chicken egg yolks contain a small amount of fat. People on a low-cholesterol diet may need to cut down on egg consumption, although most of the fat in egg is unsaturated fat and may not be harmful. The egg white consists primarily of water (87%) and protein (13%) and contains no cholesterol and little, if any, fat.Some people try to avoid eggs in their diet because they are high in cholesterol, which is concentrated in the yolk. This issue is sometimes addressed by eating only some or none of the yolk. People sometimes remove the yolk themselves, or may use prepared egg substitutes such as Egg Beaters.There is debate over whether egg yolk presents a health risk. Some research suggests it may lower total Low density lipoprotein ("bad" cholesterol) while raising High density lipoprotein ("good" cholesterol) levels.[citation needed] Some people advocate the eating of raw eggs and egg yolks for this reason, claiming that uncooked cholesterol in the yolk is healthier than when it is cooked.The United States egg industry launched its continuing "Incredible Edible Egg" campaign, which touts eggs as a healthy part of a balanced diet. The American Egg Board publicizes modern research which shows that dietary cholesterol has less effect on blood cholesterol than previously thought. Nutritive Value Eggs provide protein, vitamin A, riboflavin, and other vitamins and minerals. The yolk contains all the fat, saturated fat, and cholesterol in an egg. In 1 large egg, the yolk contains 5 grams total fat, 2 grams saturated fatty acids, 213 milligrams cholesterol, and 60 calories. The egg white contains 15 calories. Use the Nutrition Facts panel on each individual product label to learn about the nutrient content of that food and how it fits into an overall daily diet. Choose a diet low in fat, saturated fat, and cholesterol to help reduce the risk of getting certain diseases and to help maintain a healthy weight. The Dietary Guidelines for Americans suggest choosing a diet containing 30 percent or less of calories from fat, and less than 10 percent of calories from saturated fatty acids. Also, some health authorities suggest that dietary cholesterol be limited to an average of 300 milligrams or less per day.The Food Guide Pyramid suggests 2 to 3 servings each day of food from the meat group, the equivalent of 5 to 7 ounces of cooked lean meat, poultry, or fish. Because egg protein is of high quality, eggs are an alternative to lean meat, poultry, and fish. Count one whole egg as 1/3 serving, and remember that egg yolks should be limited to four per week. Tips: Substitute 2 egg whites for each whole egg in muffins, cookies, puddings, and pie fillings. Some specialty egg products are available, such as liquid whole eggs that are lower in fat and cholesterol, liquid products made without yolks, and dried whites for cake decorators. When you choose a whole egg, balance your cholesterol intake by choosing other foods that are low in cholesterol. Protein Vitamin A Fats Omega 3 Cholesterol riboflavin Vitamin B6, B12, and folic acid

10 STORING Egg Storage Eggs are a perishable food and need to be refrigerated. Keep eggs in the original carton in the coldest part of your refrigerator. Throw away any eggs that are cracked, broken, or leaking. It is best not to wash eggs before storing or using them. Washing is a routine part of commercial egg processing and the eggs do not need to be rewashed. Buying and Storing Tips Only buy refrigerated eggs with clean, unbroken shells. It is best not to wash eggs before storing or using them. Washing is a routine part of commercial egg processing and the eggs do not need to be rewashed. At home, keep raw eggs in their original carton on an inside shelf in the refrigerator (40 。F). For best quality, use within 5 weeks after bringing them home. Keep hard-cooked eggs (in the shell or peeled) in the refrigerator (40 。F). Use within 1 week after cooking. Most eggs sold today are infertile; roosters are not housed with the laying hens. Shell color depends on the breed of the hen. Yolk color depends on the feed the hen consumes. There is no nutritional difference between fertile and infertile eggs, brown- and white-shelled eggs, or pale or dark egg yolks. 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. ハIs Fresh eggs in the shell - 3 to 4 weeks Fresh egg whites - 2 to 4 days Fresh egg yolks (unbroken and covered with water) - 2 to 4 days Hard-cooked eggs - 1 week Deviled eggs - 2 to 3 days Leftover egg dishes - 3 to 4 days

11 Eggs in cooking Commercially, the term 'egg' refers to hen's eggs.ハ Eggs from ducks, geese, quails, ostriches are also sold but they must be labeled accordingly.Egg is the reproductive body laid by the female encased in a round or oval shell.ハ The egg consists of the thick, clear white (albumen),ハ approximately 60% of total weight of egg, and a yellow yolk, approximately 30% of total weight of egg.ハ The white is 87% water and 10% protein.ハ The protein in egg whites coagulate at 150 degrees F (65 degrees C).ハ The yolk consists of 50% water, 16% protein and 32% fat.ハ The protein in the yolk coagulates at 158 degrees F (70 degrees C).Eggs, as well as flour, are the structural ingredients in baking. Eggs provide leavening; add color, texture, flavor and richness to the batter. They are very important in helping to bind all the other ingredients together. Beaten eggs are a leavening agent as they incorporate air into the batter, which will expand in the oven and cause the cake to rise. Some cakes use beaten eggs as their only source of leavening. Eggs are also used as a thickener in custards and creams, and to glaze pastries and breads. Egg whites are used to make meringues.Eggs are inspected and graded according to their freshness and quality. The color of the eggshell (brown or white) is determined by the breed of hens and they have the same nutritional content. The color of the yolk is dependent on the hen's diet.ハ The grading system established by the USDA is AA, A, and B and refers to the egg's exterior and interior qualities, not the size of the egg.ハ The egg size ranges from jumbo, extra large, large, medium, and small. Grade AA means the egg has a firm yolk and a thick white, which does not spread. Grade A eggs have round yolks, thick whites, but have more thin whites than Grade AA. If the egg carton is labeled "fancy fresh" this means the eggs are less than 10 days old. Always check the carton of eggs before buying to make sure there are no cracked eggs. Eggs must be refrigerated and usually keep one month refrigerated. Eggs shells are porous and therefore pick up odors easily, so store eggs in their carton away from strong odors (e.g. Onions). Do not store eggs at room temperature, as eggs will deteriorate more in one day at room temperature than one week refrigerated.Once cracked, eggs will keep in the refrigerator a couple of days if tightly sealed. Leftover egg whites can be stored in a tightly sealed container in the refrigerator for 7-10 days or frozen for a month. A good way to freeze egg whites is to place them in individual plastic ice cube trays. Once frozen, transfer the whites to a plastic freezer bag. To thaw, simply place in refrigerator overnight. After freezing, the whites tend to be watery and are best used in recipes where the whites are not the sole leavening agent.Eggs contain a yolk and a white (albumen). The egg yolk is rich in fat and a source of vitamins and minerals. A fresh egg yolk will be rich in color and will stand upright with little spread. Blood spots are not harmful and will disappear with age. Egg yolks add tenderness and color to baked goods. Some recipes call for beating egg yolks and sugar until thick, light, and forms a ribbon. This means beating the yolks and sugar together until the batter will drop from the beaters in a slow ribbon-like shape (this takes about five minutes at high speed).The egg white is mostly protein. To get maximum volume when beating egg whites they should be at room temperature and make sure your bowl and beaters are clean and free of grease. Copper is the best type of bowl to use. If whites are over beaten the protein molecules will lose their elasticity and the whites will become dry and flaky and won't hold as much air. If this happens, add another white and beat again only until the whites are creamy and glossy. When adding beaten egg whites to your batter, always fold the whites into the heavier mixture. Not vice versa. Fold gently and quickly so as not to deflate the mixture. Add the egg whites in three stages using a rubber spatula. Cut down and through the batter making sure not to over mix. A few unmixed parts are fine as the most important thing is not to deflate the egg whites.It is best to separate eggs when they are cold. Make sure you do not get any yolk in with the white, as it will reduce the volume of the whites when whipping. When separating eggs have three bowls ready. Crack the egg in half and let the white drain into one bowl by transferring the yolk between the two halves of the shell. When done, put the yolk in the second bowl. When breaking the second egg, use the third bowl for the new egg white, so if some yolk gets mixed in with the white, you have not wrecked all your whites. If you do happen to get some egg yolk in with the white, remove the unwanted yolk by using an empty eggshell. Egg yolks will immediately start to form a skin after being separated. Cover the yolks with plastic wrap, if you need to bring them to room temperature before using.Always use the size egg that is called for in the recipe. If the size is not given, assume it is large. Most eggs used in baking are at room temperature. A quick way to warm eggs to room temperature is to place them in warm water for minutes, or else leave them out for minutes..ハハ

12 Mrs. Wilcox What is the History of the Egg?Eggs existed long before chickens, according to On Food and Cooking: The Science and Lore of the Kitchen by Harold McGee. These all-in-one reproductive cells, incorporating the nutrients to support life, evolved about a billion years ago. The first eggs were hatched in the ocean. As animal life emerged from the water about 250 million years ago, they began producing an egg with a tough leathery skin to prevent dehydration of its contents on dry land. The chicken evolved only about 5,000 years ago from an Asian bird. f you believe in the Bible, the chicken came first. "And the evening and the morning were the fourth day. And God said, 'Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven'." Genesis 1: Chickens are a type of fowl, so the Christian Bible says that chickens came first. If you have a different religion, you might have a different belief about the how the treasures of the earth came to be. In the science of evolution, both chickens and eggs came before man. Since both the birds and the eggs were on earth first, historians weren't around to record which came first. Whichever answer you gave, it's okay. A chicken can't be born without a chicken egg and a chicken egg can't be laid without a chicken. Both chickens and eggs are important!



15 When you start with a portrait and search for a pure form, a clear volume, through successive eliminations, you arrive inevitably at the egg. Likewise, starting with the egg and following the same process in reverse, one finishes with the portrait. Pablo Picasso

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