Unofficial: JNHS Cookery 9&10

Unofficial: JNHS Cookery 9&10 updated their business hours.

SEPTEMBER 9-13, 2019

LESSON 2
PREPARE AND COOK SEAFOOD DISHES

Overview
Seafood is any form of sea life regarded as food by humans. Seafood includes fish and shellfish. Shellfish include various species of mollusks, crustaceans, and echinoderms. A wide variety of fish and seafood are available in the market from many different sources. There are so many methods for cooking seafood, most of them are fast and easy, making them the perfect choice for a quick and healthy meal. This lesson provides information about fish and shellfish, ways on preparing and cooking fish, along with some of the most popular seafood recipes, and presenting and storing seafood.
Classifications of Seafood
Fish products are divided into two categories
1. Fin fish – fish with fins and internal skeletons
A. Saltwater fish
a. Flatfish -
Flounder
Sole
b. Round fish
Black sea bars Bluefish

Cod

Grouper
B. Freshwater fish
Cat fish 

Eel 

Tilapia 

2. Shell fish – fish with external shells but no internal bone structure. They have hard outer shells.
Two classifications of Shellfish
A. Mollusks – are soft sea animals
Bivalves – they have a pair of hinged shells (clams, oysters) 

Univalves – they have a single shell (abalone)
Cephalopods – (octopus, squid) 

B.Crustaceans – are animals with segmented shells and jointed legs (shrimps, crabs) 


Composition and Structure:
Fish consists of water, protein, fats and small amount of minerals and vitamins.
Fish has very little connective tissue. It means:
1. Fish cooks very quickly, even at low heat.
2. Fish is naturally tender. High heat will result to toughening of protein.
3. Moist-heat methods are used not to create tenderness but to preserve 
moistness and provide variety.
4. Cooked fish must be handled very carefully.

Fat Fish -- are those that are high in fat. (salmon, tuna, trout, mackerel)
Lean Fish – are those that are low in fat. (sole, cod, red snapper, bass)

September 5, 2019

Vegetable Dishes Performance Output of Cookery 10

JUNE-AUGUST

THE SUMMATIVE TEST OF COOKERY 10 WILL BE SENT THRU MESSENGER. PLEASE SEND ME A PRIVATE MESSAGE ON MY FB ACCOUNT.

Cereals are usually starchy pods or grains. Cereal grains are the most important group of food crops in the world named after the Roman goddess of harvest, Ceres. Rice, wheat and corn are the three most cultivated cereals in the world. Starch on the other hand, exists in nature as the main component of cereals and tubers. In manufactured and processed foods, it plays an obvious role in achieving the desired viscosity in such products as cornstarch pudding, sauces, pie fillings, and gravi
Starch is the second most abundant organic substance on earth. It is found in all forms of leafy green plants, located in the roots, fruits or grains. Many of the food staples of man throughout the world are basically starchy foods, such as rice, corn, cassava, wheat, potato and others. Starch is the source of up to 80% of calories worldwide. Besides this significant role, starches have been used in food manufacture, cosmetics, pharmaceuticals, textiles, paper, construction materials, and other industries.
Tools and Equipment Needed
The success of cooking starch and cereal dishes depends on the proper tools and equipment used in the preparation of food. The preparation of starch and cereal dishes requires the various tools and equipment below. Each tool must be used according to its function.
1. Mixing bowl – used when preparing cake mixture, salads, creams, and sauces. 

2. Sifter – used for separating coarse particles of flour, sugar, baking powder, and powdered ingredients to retain finer textures. 
products as cornstarch pudding, sauces, pie fillings, and gravies.
3. Wire whip – used for beating egg whites, egg yolk, creams and mayonnaise. 

4. Wooden spoon – used for mixing creams, butter, and for tossing salads. 

5. Slotted spoon – used to separate solid particles from soup; also for stirring purposes, such as making egg white fine in texture for bird‘s nest soup and mock nido soup. 

6. Blending fork – used for testing the tenderness of meat, combining big cuts and particles of meat and vegetables, and for blending other ingredients with flour. 

7. Rubber scraper – used for scraping off mixtures of butter, sugar, and egg from the sides of the mixing bowl. 

8. Strainer – used for separating liquids from fine or solid food particles, such as coco cream from coconut and tamarind extract.
9. Tongs – used for handling hot foods.
10.Measuring Cups – used for measuring dry and liquid ingredients 11.Measuring spoon – used for measuring dry and liquid ingredients
which require a little amount
12.Sauce pan and pots – used for cooking meat and fish dishes with
gravy and sauce.
13.Kettle and rice cooker – used for cooking rice and other foods. 14.Pressure cooker – used for tenderizing or cooking meat, chicken, and
other grains or legumes, such as mongo and white beans in lesser
time..
15.Double boiler – used for preparing sauces which easily get scorched
when cooked directly on the stove.
16.Steamer – used for cooking food by steaming.
17.Colander - a perforated bowl of varying sizes made of stainless steel,
aluminum or plastic, used to drain, wash, or cook ingredients from
liquid
18.Canister - a plastic or metal container with a lid that is used for keeping
dry products
19.Butcher knife – used for cutting, sectioning, and trimming raw meats 20.Channel knife – a small hand tool used generally in decorative works such as making garnishes.
Sources of Starch
The parts of plants that store most starch are seeds, roots, and tubers. Thus, the most common sources of food starch are:
cereal grains, including corn, wheat, rice, grain, sorghum, and oats; 

legumes; and
roots or tubers, including potato, sweet potato, arrowroot, and the 
tropical cassava plant (marketed as tapioca) 
Common Source of Manufactured Food Starch 

1. corn 

2. potato 

3. T apioca (cassava) 

Starches are named after its plant sources
corn starch from corn 

rice starch from rice 

tapioca from cassava 
Classification of Starch 

1. Native or Natural Starch refers to the starches as originally derived from its plant source. 

2. Modified Starches are starches that have been altered physically or chemically, to modify one or more of its key chemicals and/or physical property. 

3. Purified starch may be separated from grains and tubers by a process called wet milling. This procedure employs various techniques of grinding, screening, and centrifuging to separate the starch from fiber, oil, and protein. 

Starch Composition and Structure The Starch Molecule
Starch is polysaccharide made up of hundreds or even thousands of glucose molecules joined together. The molecules of starch are two general types, called fractions: amylose and amylopectin.
Amylose is a long chain-like molecule, sometimes called the linear fraction, and is produced by linking together 500 to 2, 000 glucose molecules. The amylose fraction of starch contributes gelling characteristics to cooked and cooled starch mixtures. A gel is rigid to a certain degree and holds a shape when molded.
Amylopectin has a highly branched, bushy type of structure, very different from the long, string-like molecules of amylose. In both, amylose and amylopectin, however, the basic building unit is glucose. Cohesion or thickening properties are contributed by amylopectin when a starch mixture is cooked in the presence of water, but this fraction does not produce a gel.
Most natural starches are mixtures of the two fractions. Corn, wheat, rice, potato, and tapioca starches contains 24 to 16 percent amylose, with the remainder being amylopectin. The root starches of tapioca and potato are lower in amylose content than the cereal starches of corn, wheat, and rice.
Starch Properties and Reactions
1. Gelatinization.The sum of changes that occur in the first stages of heating starch granules in a moist environment which includes swelling of granules as water is absorbed and disruption of the organized granule structure.
2. Viscosity. The resistance to flow; increase in thickness or consistency. When the newly gelatinized starch is stirred, more swollen granules break and more starch molecules spill causing increase in viscosity or thickness.
Learning Outcome 2 Prepare and Cook Starch and Cereal Dishes
One of the properties of starch is viscosity which is the resistance to flow of starch and modified starch paste. In the preparation and cooking of starch and cereal dishes, factors affecting starch paste viscosity and starch gel strength should be considered.
Factors Affecting Starch Paste Viscosity and Starch Gel Strength
Stress or other factor. Stirring Amount and Type. This is a gelatinized cornstarch dispersion that is likely to break; the granules broke apart due to stirring. 

Kind and Amount of Starch. Certain type of starch will influence the characteristics of the starch paste viscosity and gel strength. Generally speaking, with "native starches" the greater the amount of amylopectin the more viscous the starch paste, whereas, the greater the amount of amylase, the firmer the gel is (greater the gel strength). 

Heating rate. The faster starch-water dispersion is heated; the thicker it will be at the identical endpoint temperature. 

Endpoint Temperature
Each type of starch has a specific endpoint temperature at 
which it will undergo optimum gelatinization. 

Incompletely gelatinized starch will not attain optimum starch 
paste viscosity or gel strength. 

Over gelatinization results in decreased starch paste viscosity 
and gel strength because the swollen granules fragmented with stirring and/or imploded due to the extensive loss of amylase from the granule. 

Cooling and storage conditions
If cooled too fast, the amylase will not have time to form the 
vital micelles necessary for the three dimensional structure. 

If cooled too slowly, the amylase fractions will have a chance to align too much and become too close together and the liquid portion will not be trapped in the micelles. In both instances 
there will be weeping and syneresis


Common Problems in Starch Cookery
1. ThinningofGel.Thisproblemisusuallyencounteredwhenusingacid or acid ingredients such as lemon or vinegar. 

2. WeakGel.Weakgelresultsifthereistoomuchliquidinrelationtothe starch 

3. Skin Formation. Skin formation is due to loss of water from the starch and protein molecules near the surface of the mixture. To reduce this problem, cover container of the starch gel with a waterproof cover. 

4. Scorching. This can be avoided by temperature control and constant stirring so the starch granules do not settle at the bottom of the cooking pan. 

5. Raw Starch Flavor. This is due to ungelatinized starch.
Principles in Cooking Cereals
In cooking all cereal products, the following points should be observed:
1. Useadoubleboiler.
2. Observe carefully the correct proportions of cereal, water and salt.
3. Cook at boiling temperature (212° F.).
4. Watch the time by the clock, and always cook the full time prescribed, preferably longer.
5. Serveattractively. 

6. Improper cooking and poor serving are largely responsible for 
unpopularity of cereal foods 

Cooking Pasta
Pasta should be cooked al dente, or ―to the tooth‖. This means the cooking should be stopped when the pasta still feels firm to the bite, not soft and mushy. The pleasure of cooking pasta is its texture, and this is lost if it is overcooked. To test for doneness, break pasta into small piece and taste it. As soon as pasta is al dente, cooking must be stopped at once. Half a minute extra is enough to overcook it.
Cooking times differ for every shape and size of pasta. Timing also depends on the kind of flour used, and the moisture content.
Fresh egg pasta, if it has not been allowed to dry, takes only 1 to 1 1⁄2 minutes to cook after the water has returned to a boil.
Italian practice is to toss the pasta with the sauce the minute it is drained, the sauce immediately coats all surfaces of the pasta, and the cheese, melts in the heat of the boiling hot noodles.
Basic Principles in Preparing Pasta Pasta Shapes
There are hundreds of shapes and sizes of pasta with each shape used for different preparations based on how the sauce will cling, the texture desired, or how the product will be used. For example:
• Pasta shapes with holes or ridges, such as wagon wheels or rotini, are perfect for chunkier sauces. 

• Thin, delicate pastas, such as angel hair or vermicelli, are better served with light, thin sauces. 

• Thicker pasta shapes, such as fettuccine, work well with heavier sauces. 

• Very small pasta shapes, like alphabet shapes and acini di pepe, are good for soups. 

. Cooking Time Depends on the Shape 
It is important to be familiar with different shapes of pasta so cooking times can be adjusted. The larger and fuller the pasta shape, the longer the cooking time. Most pasta recipes specify cooking times for pasta cooked al dente, tender but firm. Al dente is an Italian phrase that means ―to the tooth.‖ Some of the pasta shapes and cooking times are shown in the ―Cooking Chart for Various Pasta Shapes.‖ Just seeing this chart helps to emphasize how important it is to follow the recipe and cook pasta the right way
Pasta Gets Bigger and Heavier when Cooked
Generally, pasta doubles or triples in weight when it is cooked. Likewise, the volume increases 2 to 2 1⁄2 times during cooking.
Follow the Recipe
The general rule for cooking pasta in boiling water is for 1 pound of pasta, use 1 gallon of water, 1 teaspoon of salt, and 1 teaspoon of oil. For 100 servings of spaghetti, 6 gallons of water, 2 tablespoons of salt, and 2 tablespoons of oil are needed to cook 6 pounds of dried spaghetti.
When pasta is to be used as an ingredient in a recipe that will be cooked more, like macaroni and cheese, it should be slightly undercooked. This means reducing the cooking time by about 2 minutes. Pasta that is not cooked enough is tough and chewy. Pasta that is overcooked is soft and pasty. When overcooked pasta is combined with a sauce, it often breaks apart. Handle pasta the right way after it is cooked. Like most foods, pasta is best when it is cooked and served right away. However, it is sometimes necessary to cook it ahead and hold it until time for service.

Prepare Egg Dishes
In cookery, egg refers to poultry or fowl products. The versatility of eggs is evident in its presence in numerous food items. Eggs may be eaten cooked in its shell, fried or poached or may be combined with other ingredients to produce another dish. In baking, egg acts both as an emulsifier and leavener.
The egg‘s protective coating or mucin layer which aids in the maintenance of its freshness by covering the small holes in the shell is called bloom. Bloom is removed during washing so it is not advisable to wash eggs prior to storage unless it is very dirty. Removal of the mucin layer will expose the holes making the egg susceptible to bacterial pe*******on and dehydration, thus hastening deterioration of its quality.
Eggs are produced commercially in farms with a few hundred laying chickens, or in large laying complexes with thousands of layers. Small and micro-sized backyard poultry either in small poultry cages or as free range chicken are also producing eggs. Egg is indeed a convenient food for any meal in and out of the house.
Learning Outcome 1 Perform Mise’en Place
At the end of the lesson, you are expected to:
1. identify tools, utensils and equipment needed in egg preparation; 

2. clean, sanitize and prepare tools, utensils and equipment needed 
in preparing egg dishes; 

3. identify egg components and its nutritive value; and 

4. identify and prepare ingredients according to standard recipe. 

In the preparation of egg dishes, the first consideration is to identify the needed tools and equipment and how to clean and sanitize them after each use.
Tools, Utensils and Equipment Needed In Egg Preparation Kitchen Tools
1. Channel Knife – a small hand tool used generally in decorative works such as making garnishes.
2. Colander – a perforated bowl of varying sizes made of stainless steel, aluminum or plastic, used to drain, wash or cook ingredients from liquid.
3. Offsetspatula–abroad–bladedimplementbenttokeepthehandoff hot surfaces. It is used for turning and lifting eggs, pan cakes, and meats on griddles, grills, sheet pans, and the likes and also used to scrape and clean griddles.
4. PastryBrush–asmallimplementusedtobrushthesurfaceof unbaked pastries or cookies with egg white, egg yolk or glaze.
5. Rubber spatula or scraper – a broad flexible plastic or rubber scraper, that is rectangular in shape with a curve on one side. It is used to scrape off all the contents of bowls and pans from the sides and fold in beaten eggs in batter or whipped cream. 

6. Sieve–ascreen–typemeshsupportedbyaroundmetalframeused for sifting dry ingredients like starch and flour.
7. Spoons: solid, slotted and perforated – large stainless spoons holding about 3 ounces used for mixing, stirring, and serving. Slotted and perforated spoons are large, long-handled spoons with holes in the bowl used to remove larger solid particles from liquids.
8. Wire whip or Whisk – a device with loops of stainless steel wire fastened to a handle. It is used for blending, mixing, whipping eggs or batter, and for blending gravies, sauces, and soups. 
Kitchen Utensils
1. Egg Poacher – A miniature Bain Marie with an upper dish containing indentations each sized to hold an egg or contains separate device for poaching.
2. Omelet Pan – a heavy-based frying usually of cast iron or copper, with rounded sloping sides used exclusively for omelets and never washed after used but cleaned with absorbent paper.
3. Measuring cup- a kitchen utensil used for measuring liquid or bulk solid cooking ingredients such as flour and sugar
4. Measuringspoon-usedtomeasureanamountofaningredient,either liquid or dry, when cooking. Measuring spoons may be made of plastic, metal, and other materials.
5. Sauce pan- deep cooking pan with a handle used primarily for cooking sauce. 

6. Mixing bowl - these containers have smooth, rounded interior surfaces with no creases to retain some mixture and is used for mixing ingredients.
Kitchen Equipment
1. Oven - a chamber or compartment used for cooking, baking, heating, or drying.
2. Electric mixer - A hand-held mixer which usually comes with various attachments including a whisk attachment for whisking cream, batters and egg whites, and sugar.
3. Refrigerator - a kitchen appliance where you store food at a cool temperature. 

Cleaning and Sanitizing Tools and Equipment
A cleaning program that is an overall system should be prepared to organize all your cleaning and sanitizing tasks. The program should also help identify your cleaning needs, set up a master cleaning schedule, select the supplies and tools to use, and train yourselves to make the best of your skills.
Cleaning is the removal of visible soil while sanitizing means reducing the number of harmful microorganisms by using very hot water or a chemical sanitizing solution. To be effective, cleaning and sanitizing must be two-step process. Surfaces must first be cleaned and rinsed before being sanitized.
There are many cleaning products or agents and a variety of equipment in the market. Choose the best for your workplace and follow instructions in the label.
Here are some points to support your workplace training:
1. Clean in a logical order.
2. Different cleaning tasks require different methods. Getting things wrong can cause damage to surface, harm to yourself, and spread bacteria and dirt.
3. Many cleaning agents are harmful. Their contact with your skin or eyes or breathing in the fumes can cause a serious illness.
4. Mixing one agent with another can be very dangerous. A chemical reaction can be set up, or in some cases, produce poisonous fumes. 

Ware washing
Ware washing is the process of washing and sanitizing dishes,
glassware, flatware, and pots and pans either manually or mechanically. Manual ware washing uses a three-compartment sink and is used primarily for pots and pans. It may be used for dishes and flatware in small operations. Mechanical ware washing requires a dishwashing machine capable of washing, rinsing, and drying dishes, flatware, and glassware. In large operations, heavy-duty pot and pan washing machines have been designed to remove cooked-on food.
Manual Dishwashing Procedure
1. Scrape and pre-rinse.
The purpose of this step is to keep the wash water cleaner 
longer.
2. Wash. 
Use warm water at 1100F to 1200F and a good detergent. Scrub well with a brush to remove all traces of leftover and grease. 

3. Rinse.
Use clean warm water to rinse off detergent. Change the 
water frequently, or use running water with an overflow.
4. Sanitize. 
Place utensils in rack and immerse in hot water at 1700F for thirty seconds. (A gas or electric heating element is needed to hold water at this temperature.)
5. Drain and air-dry.
Do not towel-dry. This may contaminate utensils. 

Mechanical Dishwashing
The steps in washing dishes by machine are the same as in the
manual methods. Except that the machine does the washing, rinsing, and sanitizing.
Procedure
1. Scrape and pre-rinse.
2. Rack dishes so that the dishwasher spray will strike all surfaces.
3. Run machine for a full cycle.
4. Setthesanitizingtemperaturesat1800Fformachinethatsanitizes 
by heat and at 1400F for machine that sanitizes by chemical 
disinfectant.
5. Air-dryandinspectdishes.Donottouchfood–contactsurfaces.
Physical Structure and Composition of Eggs
We normally distinguish 3
parts of an egg, the shell, the egg white, and the egg yolk, but a closer scrutiny reveals a much more detailed structure of an egg.
Structure
1. Shell. The
egg‘s outer covering, the shell, accounts for about 9 to 12 % of its total weight depending on egg size. The shell is the egg‘s first line of defense against bacterial contamination.
The shell is produced by the shell gland (uterus) of the oviduct, and has an outer coating, the bloom or cuticle. The cuticle somewhat seals the pores and is useful in reducing moisture losses and in preventing bacterial pe*******on of the egg shell.
2. Air cell. This is the empty space between the white and shell at the large end of the egg which is barely existent in newly laid egg. When an egg is first laid, it is warm. As it cools, the contents contract and the inner shell membrane separate from the outer shell membrane to form the air cell. 

3. Albumen/Egg white. Albumen, also called egg white, accounts for most of an egg‘s liquid weight, about 67%. This is produced by the oviduct and consists of four alternating layers of thick and thin consistencies. From 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. The outer thin white is a narrow fluid layer next to the shell membrane. The outer thick white is a gel that forms the center of the albumen. The inner thin white is a fluid layer located next to the yolk. The inner thick white (chalasiferous layer) is a dense, matted, fibrous capsule terminates on each end in the chalazae, which are twisted in opposite directions and serve to keep the yolk centered. 

4. Chalaza. This is the ropey strands of egg white at both sides of the egg, which anchor the yolk in place in the center of the thick white. They are sometimes mistaken for egg imperfections or beginning embryos, which of course they are not. The twist in the chalaza is meant to keep the germinal disc always on top whichever way the egg may turn. The more prominent the chalazae the fresher is the egg. 

5. Germinal Disc. This is 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, s***m enter by way of the germinal disc, travel to the center and a chick embryo starts to form. Since table eggs are not fertilized, this is not as easy to recognize as when the egg is fertilized. 

6. Membranes. There are two kinds of membranes, one just under the shell and the other covering the yolk. These are the shell membrane and the vitelline membrane. Just inside the shell are two shell membranes, inner and outer. The air cell formed due to the contraction of egg as it cools, is found between the two layers of this shell membrane. The outer membrane sticks to the shell while the inner membrane sticks to the albumen. During storage, the egg losses water by evaporation, causing the air cell to enlarge. The vitelline membrane is the covering that protects the yolk from breaking. The vitelline membrane is weakest at the germinal disc and tends to become more fragile as the egg ages. Every cook has experienced that the yolk of eggs that are no longer fresh easily break. 

7. Yolk. The yolk or the yellow to yellow- orange portion makes up about 33% of the liquid weight of the egg. The egg yolk is formed in the o***y. On the surface of the yolk, there is a small white spot about 2 mm in diameter. This is the germinal disc and it is present even if the egg is infertile. In infertile eggs, the germinal disc contains the genetic material from the hen only but when fertilized, it contains the zygote that will eventually develop into a chick. The yolk material serves as a food source for embryonic development. It contains all the fat in the egg and a little less than half of the protein. The main protein in the egg yolk is vitelline, a lipoprotein. It also contains phosvitin which is high in phosphorus and has antioxidant properties, and livetin which is high in sulfur. 

Composition of an Egg
Nutritive Value of Egg
Egg is indeed one of nature‘s complete food. It contains high quality protein with all the essential amino acids, all of the vitamins except vitamin C, and many minerals. Egg products are particularly good for fortifying food low in protein quality. Except for mother‘s milk, eggs provide the best protein naturally available. Egg protein is often used as a reference standard for biological values of their proteins.

Market Forms of Egg
There are three market forms of eggs namely: fresh, dried (whole, egg whites/egg yolks), and frozen (whole, egg whites/egg yolks).
1. Fresh Eggs or shell eggs may be purchased individually, by dozen or in trays of 36 pieces.
2. Frozen Eggs – are made of high quality fresh eggs. They come in the form of whole eggs with extra yolks and whites. Frozen eggs are pasteurized and must be thawed before use.
3. Dried Eggs – are seldom used. Their whites are used for preparing meringue. Dried eggs are used primarily as ingredients in food industry. They are not commonly sold directly to consumers. 
Eggs are also sold in several processed forms: bulk or fluid 

whole eggs (which sometimes includes a percentage of extra yolks to obtain a specific blend), egg whites, and egg yolks. Pasteurized eggs are used in preparations such as salad dressings, eggnog, or desserts, where the traditional recipe may have indicated that the eggs should be raw. These products generally are available in liquid or frozen form. Frozen egg products on the other hand are used as ingredients by food processors. Products containing egg yolk usually have salt, sugar or corn syrup added to prevent gelation or increased viscosity during freezing. They are packed in 30- lB.containers and in 4-, 5-, 8-, and 10-lB.pouches or waxed or plastic cartons.
Dried powdered eggs are also sold and may be useful for some baked goods or in certain circumstances. For food service use, they are generally sold in 6-oz. pouches, and 3-lB.and 25-lB.poly packs.
Egg substitutes may be entirely egg-free or may be produced from egg whites, with dairy or vegetable products substituted by yolks. These substitutes are important for people with reduced-cholesterol diet requirement.

Uses of Eggs in culinary
Egg is cooked in many ways. It can be the main protein dish; it can be a main or accessory ingredient in dishes from appetizers to desserts. It can be cooked by dry heat, moist heat, with or without oil, as simply or as elaborately as one‘s inclination for the moment. Indeed it can be eaten anywhere.
Effect of Heat on Eggs
1. Coagulation of proteins: white at 60-65 0C, yolk at 65-700C.
Beyond this temperature, over coagulation occurs and water is squeezed out causing shrinkage resulting in a
tough product.
2. Formation of greenish discoloration at the interface of the yolk and
white when egg is overcooked
Due to the reaction between the iron in the yolk and the 
hydrogen sulfide liberated from the sulfur containing ferrous 
sulfide. 

Reaction is favored by
- High cooking temperature 

- Prolonged cooking 

Reaction is prevented by immediate cooling of the egg (e.g. 
immersing in cold water) after cooking 
Uses of Egg
1. Cooked and served ―as is‖, e.g. 

in the shell – soft cooked ( 5 minutes simmering) or hard cooked (15 minutes simmering) 

poached – cooked in simmering water; addition of salt and vinegar hastens coagulation 

fried – keep low to moderate temperature 

scrambled – addition of sugar delays coagulation; addition of liquids 
and acids decreases coagulation point 

omelet 
2. Eggs as emulsifier 

Lecithin and lysolecithin are responsible for the remarkable ability of
egg yolk to act as an emulsifying agent; both are phosphoproteins containing polar and non-polar ends such that the polar end holds water while the non-polar end holds the fat, thus, prevent oil droplets in suspension from coalescing.
3. As binding, thickening agent, and gelling agents
Eggs are useful as binding, thickening and gelling agents because they 
contain proteins that are easily denatured by heat 

Using whole egg requires lower coagulation temperatures resulting in a 
stiffer gel 

Addition of sugar, raises coagulation temperature producing softer, 
weaker gel 

Softer gel is produced with the addition of scalded milk and acid 

In cooking custards, Bain Marie, double boiler or steamer is used to 
avoid boiling which can produce a porous custard 

Soft custards are produced by constant stirring. 
4. As foam 

When egg is beaten albumen is denatured, air is incorporated as white 
is stretched into thin films 

With continued beating, the air cells are subdivided and volume is 
increased 

Protein network dries up and stabilizes the gas or air foams
- If only egg whites are used, the color turns white and soft peaks are formed. The egg proteins collect at the air/liquid interface of the air bubble and undergo surface denaturation. 

- If whole eggs or only egg yolks are used, the color becomes pale yellow with continued beating; volume is increased (but not as much as when only whites are used); no surface denaturation occurs. 

- With further beating of egg whites, liquid drains out, air bubbles coalesce and foam breaks. 

- The same changes occur when the foam is allowed to stand too long. 

- Maximum stability is reached at soft stage while maximum volume attained is at stiff stage 

- Stages in foam formation
A. frothy – large air bubbles that flow easily
B. soft foam – air cells are smaller and more numerous; foam 
becomes whiter; soft peaks are formed when be**er is lifted C. stiff foam – peaks hold their shape; when bowl is tipped, it 
holds, moist and glossy
D. dry – moistness and glossiness disappear; specks of egg
Factors to be considered in foam formation (leavening agent)
a. Beating time and temperature: as the time of beating 
increases, both volume and stability of the foam increases initially, then, decreases; white can be beaten/whipped more readily at room temperature than at refrigerator temperature – refrigerated eggs are more viscous, thus, hard to beat/whip. 

b. Eggs beaten at room temperature whip better resulting in bigger volume and finer texture. 

c. Whole eggs or egg yolk require more beating to produce a good foam 

d. Stored eggs foam faster but produce smaller volume than fresh eggs. 

e. Acids (e.g. cream of tartar, 1 t per cup) increase the stability of foams, but when added too early, delay foam formation (reduced volume) thus, increases the time necessary for beating 

f. Sugar also increases the stability of foams but delays foams formation (reduced volume), thus, it should be added after foaming has started and soft peaks are formed; sugar retards the denaturation of egg white 

g. Addition of soda increases stability and volume 

h. Addition of salt lowers quality of the foam
i. Type of egg: duck eggs do not foam well because they lack 
ovumucin
j. Dilution of egg white by water produces bigger volume but 
lesser foam; this produces more tender cakes, but in 
meringues, syneresis occurs.
k. Applications of foam in cookery
as leavening e.g. in angel cake, sponge cake, chiffon cakes
as meringue, e.g.
. (a) soft meringue for topping of cream, chocolate, or lemon 
pie, requires a proportion of two tablespoons sugar per 
egg white 

. (b) hard meringue for confections, base of fruit pies or 
Sans Rival Cake, requires a proportion of 1⁄4 cup sugar 
per egg white 

structural and textural agent – tenderness and fluffiness to 
products, e.g. fluffy or foamy, soufflé, divinity, foam cakes, popovers 

5. As coloring and flavoring agent
Egg Products
1. Balut from duck eggs 2. Pidan eggs
3. Century eggs
4. Pickled eggs
Eggs may be cooked in a lot of ways:
Egg Dishes
Eggs cooked in a shell
Hard and soft-cooked eggs are cooked this way. Eggs should 
only be simmered and not boiled to prevent overcoagulation which would cause the eggs to be tough. The optimum cooking time for eggs in shells is 20 to 25 minutes. To avoid cracking of the eggs during cooking, refrigerated eggs should be warmed at ambient temperature before cooking. Before boiling, water at room temperature should be used. 
Sometimes yolks of eggs may become greenish during cooking. This color is due to the formation of iron sulfide. Darkening often occurs in eggs wherein the pH of the albumen is high. It may also be a result of cooking too long at very high temperature. 
To avoid this, fresh eggs should always be used. Eggs should be cooked within a minimum period and cooled immediately in running water after cooking. 

Eggs prepared out of the shell
This method involves breaking the egg and using both the yolk 
and white during cooking. Poaching, frying, and the process of making scrambled eggs or omelet are some of the common methods done. 
Culinary Uses: 

Eggs as a thickening agent and binder
When used as a binder or thickener, the hydrophilic colloids of
yolks and whites, due to the presence of proteins are converted into a hydrophobic colloid thus turning it into a gel.
At high temperature, the gel toughens. This explains why the white becomes an opaque mass when cooked at a temperature of 620C. For egg yolk, coagulation starts at 650C.

Eggs as leavening agent
Baked products such as sponge cakes, chiffon cakes, meringues, and
soufflés make use of eggs as leavened resulting in a light, airy texture. This is explained by the incorporation of air during the beating of eggs. Foam is formed when the albumen surrounds a colloidal system of air bubbles. When beating eggwhites, overbeating must be avoided as this tends to stretch the albumen and would result in a dry, watery appearance.
Why do you need to eat eggs?
Eggs may be considered as "functional foods". Functional foods are foods that may have health benefits beyond their traditional nutritional value. Eggs as functional foods contain lutein and zeaxanthin that reduce the risk of cataracts and macular degeneration. Eggs may also belong to "designer foods". Designer foods are foods that have been modified through biotechnology to enhance their quality or nutritional value. Eggs as designer foods contain omega-3-polyunsaturated fatty acids and vitamin E. So learn now and explore the various egg dishes below.