List and describe the five components of an eggs structure PDF

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1. List and describe the five components of an eggs structure. Yolk: nourishment, Albumen (egg white): anchors the yolk, Shell membrane: protect against bacteria, Air cell: between the inner shell & outer cell. Allows baby chick to take first breath to break out of shell, and Shell: protection. Pg 251

2. Describe the protein, fat, cholesterol, vitamin, and mineral contents of eggs. Fat: about 5 grams. Cholesterol: 213 mg/large egg. vitamins: A, E, D, K, D and certain B vitamins. Minerals: selenium, iodine, zinc, iron.pg 255

3. List the USDA quality grades for eggs and describe the methods used to grade eggs. Quality grades include: USDA Grade AA USDA Grade A USDA Grade B Grade AA and A are the grades sold at supermarkets. Three methods used to judge the quality of eggs: Candling- method based on observing eggs against a light Measuring haugh units- cracking it open onto a flat surface and looking at the height of its thick albumen. Fresh egg whites sit up tall and firm, whereas older ones spread out. Appearance- broken on a flat surface, the egg is evaluated on thickness of the albumen, prominence of the chalaze and roundness and firmness of the yolk and the shape, cleanliness and texture of the shell. Interior quality typically based on candling. Pg 2 54

4. Describe the following functions of eggs in food preparation: emulsifying, binding, interfering, and clarifying. EMULSIFYING: lecithin in egg yolks keeps liquids from separating and thickens and stabilizes foods. BINDING: high protein count causes to act as an adhesive when cooked. INTERFERING: inhibit the formation of ice crystals (added to ice cream). CLARIFYING: used to make clear soups. Pg 256

5. Explain how the following affect the quality of whipped egg whites: beating technique, tempature, bowl type, separation of eggs abd whites, sugar, fluid, salt, and acid. Egg whites are alkaline and whip easier with the addition of acid (lemon juice, cream of tartar). This makes proteins less stable and more likely to whip into foam. Salt decreases stability and volume of egg-white foam. Protein films surrounding air cells rupture, creating bubbles that are too large and unstable. Sugar stabilizes egg white foam but also inhibits coagulation of proteins. Therefore, sugar should be added at end of whipping. Egg yolk, like all fats, can interfere with whipping. Eggs should be broken in a way that reduces risk of yolks entering whites. Deep bowls with high sides allow egg whites to be picked up by beater. Plastic should not be used because they may carry a thin layer of grease that could interfere with beating. Bowl, beater and eggs should be at room temperature, which decreases surface tension of whites and allows them to whip larger and more easily. Too much time at room temp can destabilize the foam. Eggs should be beaten moderately slow and even at first, then speed should be increased when whites are half whipped and can hold shape. Pg 258/259/260

6. Describe the difference in rate of coagulation for egg whites and yolks, and explain how added ingridents change the coagulation temperature. Egg whites first start to coagulate at about 140F and become completely coagulated at 149F158F. slightly warmer temps of about 144F-158 are needed for the egg yolks to start coagulating. Adding other ingredients to eggs changes their coagulation temperature. Incorp milk into whole eggs in a custard dish increases the coagulation temperature to about 175F. sugar also increases coagulation temperature whereas the addition of salt and or acid lowers it. Pg

7. Discuss how undesirable color changes may occur during egg whites and yolks, and explain what can be done to prevent this. Undesirable color changes may occur during egg preparation when eggs are overcooked or heated at too high of a temp, the sulfur in the egg white may combine with the iron in the yolk, the cooking water, or other iron sources to form ferrous sulfride, a green colored compound with a strong odor

and flavour. In order to prevent the problem of the "green yolk" it is best to use stainless steel equipment and low cooking temps, to avoid over cooking. Pg 260/261

8. Briefly describe the process of preparing the following types of egg dishes: over easy, shirred, soufflé, and poached. Over easy- egg flipped when whites are 75 percent set. Whites completely cook, yolks still runny. Shirredwhole eggs baked in individual dishes, sometimes with other ingredients. Souffle- white sauce, egg white foam, flavoring ingredients. Poached- eggs are cracked and simmered in enough water to cover egg by at least twice its depth. Can be hard or soft poached. Pg 262/263

9. What is a meringue? Describe the potential causes of weeping and breading. Meringue - egg white foam used in desserts, made by whipping egg white into foam and then adding sugar. weeping - underbeating eggs, or by undercoagulation (putting it over cold filling). beading - undissolved sugar or overcooking. Pg 262

10. List at least six precautions that maybe taken to prevent foodborne illness from eggs. Purchase- only buy refrigerated eggs. Refrigerate promptly after purchase or during preparation. Preparation ensures that eggshells are not left in the food products, this can be a potential hazard. Consuming raw or undercooked eggs- should never be consumed, this holds especially true for people who are very young, very elderly, or immunocomprised (aids, cancer, etc). Before purchase, open carton to make sure eggs are clean and not cracked. Preparation- bake egg dishes such as quiches, baked custards, and most casseroles until an inserted knife comes out clean. Pg 267/268

Brown, A. C. (2019). Understanding food: Principles and preparation (Fifth ed.). Boston, MA: Cengage.

Brown, A. C. (2019). Understanding food: Principles and preparation (Fifth ed.). Boston, MA: Cengage. !...