Eggs; identification of different types of eggs, nutritive value of eggs, factors to consider when choosing eggs and test for freshness, uses of eggs in cookery
WEEK 4
CLASS: SS 2
SUBJECT: FOOD AND NUTRITION
TOPIC: FOOD STUDY – Eggs
CONTENT:
(a) type of eggs
(b) nutritional value of eggs
(c) test for egg
(d) egg cookery
(e) Uses of eggs in cookery
Sub-Topic 1:
TYPES OF EGG
Eggs are oval objects with a thin but hard shell produced by birds or female reptiles. An egg is composed of several parts which perform different functions. Beside the shell, yolk and white, the egg contains an air cell, chalazae, a cutline membrane and shell membrane
STRUCTURE OF THE EGG
Eggs are produced by domesticated bird such as chicken, turkey, duck, goose and guinea fowl. The hen’s egg of average size weights approximately 56 g, they are covered with a hard protective shell which can be either be white or brown in colour. The colour of the bird depends upon the breed of the chicken and it is unrelated to the food value and quality of the egg. Eggs are spherical in shape with one end pointed and the other blunt.
Immediately beneath the egg shell are two inner membranes which separate at the blunt end of the egg forming what is known as air space. At the centre of the egg is the egg yolk which is held in position by two cords-like structures called Chalazae. The egg-yolk is covered by a membrane known as Vitaline membrane. Immediately after the vitaline membrane is the thick egg white. A high proportion of thick white. A high proportion of thick white is an indication of good quality of the egg.
TYPES OF EGG
(a) Fertile Egg: these are eggs that can be incubated and developed into a chick.
(b) Organic egg: are produced from hens that have been given feeds that are aided by commercial fertilizers, pesticides or herbicides.
(c) Free range Egg: a name given to egg produced by hens that have been raised outdoors.
NUTRITIONAL VALUE OF EGG
- Eggs are fantastic foods that contain a hug number of vitamins and minerals tat are required by the body for optimal health and growth.
- They provide vitamin A, B and especially a rich source of vitamin B12 and B2, D and E.
- They are rich in calcium, iron, selenium phosphorus, potassium, sodium and magnesium.
- They are low in sugar and do not contain any carbohydrate and vitamin C.
- Eggs provide essential amino acid to the body and their proteins are highly digestible.
- Protein: the protein of eggs as a whole is of good biological value and is easily digested. Eggs can therefore be used to replace meat, fish and poultry in a diet.
- Vitamins: eggs also contain some vitamins such as Vitamins A, D and B-Complex. Both egg yolk and white are good source of riboflavin and is this vitamin that is responsible for the slightly greenish tint to an egg white.
- Mineral Salts: eggs are rich in mineral salts like iron, sulphur, phosphorus and calcium.
- Water: 51 percent of the yolk of egg contains water and the white contains 87 percent. This shows that egg contains a reasonable amount of water.
- Fat: the yolk of an egg contains appreciable amount of fat than the fat which is totally devoid of fat.
A large boiled egg only contains 78calories and 5.3g fat. The fat present is saturated and not good to the body. The level of cholesterol in egg is high.
EVALUATION
1) What type of egg is known for its deep orange yolk and rich flavor?
A) Quail
B) Chicken
C) Duck
D) Ostrich
2) Which nutrient found in eggs has been shown to improve brain function and eye health?
A) Protein
B) Cholesterol
C) Vitamin A
D) Folate
3) Which of the following is not a factor to consider when choosing eggs at the grocery store?
A) The color of the eggshell
B) Whether or not the eggs are organic
C) The size of the egg
D) The date stamped on the carton
4) What is the “float test” commonly used for to determine the freshness of an egg?
A) Checking the texture of the yolk
B) Checking for cracks in the shell
C) Seeing if the egg sinks or floats in water
D) Checking the expiration date on the carton
5) What is meringue made from?
A) Egg whites and sugar
B) Egg yolks and sugar
C) Egg whites and flour
D) Egg yolks and flour
6) What is the name of a dish made with beaten egg whites, meat or vegetables, and cheese?
A) Frittata
B) Quiche
C) Omelette
D) Souffle
7) How many egg whites are typically used to make an angel food cake?
A) 1-2
B) 6-8
C) 10-12
D) 15-18
8) What kind of egg is used in the classic dish Eggs Benedict?
A) Hard boiled
B) Soft boiled
C) Poached
D) Fried
9) Which type of egg is often used in Asian cuisine, such as ramen or udon noodle dishes?
A) Pickled
B) Soft boiled
C) Hard boiled
D) Scrambled
10) What is the name of a dish made with beaten egg yolks and milk or cream, often flavored with vanilla or citrus zest and served as a dessert or breakfast item?
A) Scrambled eggs
B) Omelette
C) Quiche
D) Custard
Marking Guide.
1) B 2) A 3) A 4) C 5) A 6) D 7) D 8) C 9) B 10) D. 1) B 2) A 3) A 4) C 5) A 6) D 7) D 8) C 9) B 10) D.
Test for egg
1. WATER TEST
Fill a fairly deep bowl with salted water and carefully lower the egg into the water. A very fresh egg will immediately sink to the bottom and lie flat on its side. This is because the air cell within the egg is small. The egg would also be quite heavy.
2. EYE VIEW TEST
When an egg is held against a source of light, it should be bright to the eye and not cloudy or opaque.
3. FRESHNESS:
Another way to test for egg’s freshness is when you shaken, it should not produce any sound.
Sub-Topic 2: EGG COOKERY
Eggs are versatile, they may be boiled (hard or soft), poached, fried, scrambled, baked, used to make an omelette, pancake batter etc. They can be added to savoury or sweet dishes etc.
Methods of cooking Eggs
1. Boiling
2. Poaching
3. Frying
4. Scrambling
5. Plain omelette
USES OF EGGS IN COOKERY
1. Eggs are used to increase food value and to improve the flavour of foods to which they are added, e.g. doughnuts, banana pancakes, egg and corned beef stew
2. As a binding medium, e.g. fish cakes, yam balls
3. For coating foods for frying e.g. fish, yam balls, etc
4. As thickening agent e.g. in sauce, custard etc.
5. As a raising agent in cake making
6. For garnishing: hard boiled eggs are sliced or wedged and used for garnishing salad, etc. The yolk may be sieved and the white chopped foe garnishing, eat or fish dishes.
7. For glazing pastry, bread dough, biscuits etc, before baking
8. Eggs are valuable in the diet especially in that of growing children and invalid because they are rich in nourishment and are easily digested.
9. Eggs act as emulsifying agent, e.g. in creams like mayonnaise and cake mixture.
10. They serve as core part of the dish.
11. Eggs are used to glaze pastry before baking to give a golden brown gloss t the finished dish
12. They may be incorporate into a delicious home-made recipe, e.g. cake making, custard, puddings and nourishing drinks.
Eggs are used to increase food value and to improve the flavours of food to which eggs are added. E.g. doughnut, pan cakes e.t.c.
As a binding medium e.g. fish, cakes, yam balls.
For coating foods for frying, e.g. fish, yam balls e.t.c.
As thickening agents e.g. in sauce, custard e.t.c.
As a raising agent in cake making.
For garnishing, hard boiled eggs are sliced or wedged and used for garnishing salads.
For glazing pastry, bread dough, biscuits e.t.c. before baking.
Eggs are valuable in diet especially in that of growing children and invalids because they are rich in nourishment and easily digested.
EVALUATION
State 5 indications of egg freshness.
Describe the structure of a typical egg.
ASSIGNMENT
Draw and label the structure of an egg.
Note: eggs do not contain carbohydrate or starch; they should be combined with carbohydrate foods in order to give the necessary bulk.
FACTORS TO CONSIDER WHEN CHOOSING EGGS AND TEST FOR FRESHNESS
- When held against the source of light, it should be bright and not opaque.
- When broken, the yolk should be intact and surrounded by the egg white. A diffused yoke i.e. one in which yoke and egg white are mixed together is bad.
- When immersed in salt water, it should sink and float.
- When broken, there should be no offensive odour produced.
- When shaken, no sound should be produced if the egg is of good quality
EVALUATION
1. Give 10 uses of Eggs.
2. Explain practically how egg is used as raising agents.
3. Describe the use of eggs in cookery
4. Explain the binding property of egg in cake making
5. Describe the garnishing ability of egg in a practical you demonstrated.
6. Explain the methods of cooking eggs.
7. Describe the use of eggs in cookery.
8. Explain the process of poaching egg.
9. Draw and label the structure of an egg
10. Identify different types of eggs
11. Discuss the nutritive value of eggs.
OBJECTIVE TEST
1. In the baking of cakes, _________ is one of the uses of egg. (a) bleaching (b) raising (c) firming
2. Eggs are used to ________ except. (a) garnish (b)bind (c) dissolve
3. In water test, a good egg wills ________. (a) float (b) sink (c) break
4. When a good egg is taken close to the eye, it should be. (a) opaque (b) translucent (c) bright to the eye
5. ___________ is a method of cooking egg except. (a) boiling (b) Poaching (c) sterilizing
6. Which of the following are uses of eggs? i. Boil in hot water
ii. Serve as a coating agent
iii. add to nutritive value of the dishes
iv use as mayonnaise v. serve as glazing agent.
(a) i, ii and iii only (b) ii, iii and iv only (c) i, iv and v only (d) ii, iii and v only
7. The yolk of an egg contains
(a) carbohydrate, riboflavin and calcium
(b) protein, water, iron and sulphur
(c) carbohydrate, iron, and ascorbic acid
(d) protein, fats and vitamins
8. The dark ring between the albumen and yolk of a boiled egg is caused by ____
(a) iron in the yolk
(b) fat in the yolk
(c) protein in the yolk
(d) carotene in the yolk
9. Which of the following is not a use of an egg? (a) raising agent (b) a glaze (c) a dehydrating agent (d) an emulsifier
10. Which of the following is an indication of the freshness of an egg (a) light weight (b) smooth shell (c)pungent smell (d) strong smell