Transcript Get Crackin`: Eggs!

Get Crackin’: Eggs!
Anatomy
Nutrition
Science
Functions
Safety
The Shell’s Game
• Defends against bacteria
• Can be brown or white
• provides calcium & minerals to the growing embryo.
• small pores (holes) in the shell
–
allow the transfer of gases into and out of the egg
–
Oxygen in CO2 Out
Albumin: Egg white
• Function:
–
cushion the yolk and
embryo
– stop the entry of bacteria
into the yolk and embryo
area
•
made of water, high quality
protein and some minerals
• No Fat
Yolk
• primary food source for the growing
embryo
 source of vitamins and minerals, protein and
essential fatty acids
 1/3 of the egg's weight (without shell)
 yolk colour ranges from light yellow to deep orange,
-depends on the hen's food
• 70-80% Fat
Air Cell
 forms at the wide end of the egg as it cools
after being laid
 the fresher the egg the smaller the air cell
Cell Membrane
 two membranes on the inside of the shell
 one membrane sticks to the shell
 one membrane surrounds the white (albumen)
 the second line of defense against bacteria
 Made of thin layers of protein fibers
Yolk Membrane
• surrounds and holds the
yolk
• fresher the egg the
stronger the membrane
Chalaza
• a pair of spiral bands
• anchor the yolk in the center
of albumin (white)
•
the fresher the egg the more
prominent the chalazas
•
unnoticeable when the egg
is cooked
Whole Egg Nutrition
• excellent source of high quality protein.
• Complete Protein:
– contains all nine essential amino acids
• Egg used as a standard to measure the
protein quality of other foods
• One egg = 71 calories.
Science and Cooking
• Eggs are made up of:
– Protein
– fat
– water
• Proteins are coils
Heat and Eggs
• Heat + Protein = breakdown of coils
• Protein uncoils and becomes tangled
– Bonds with other protein strands
• Coagulation: Proteins forms a Tangled web (Cooked Egg)
Coagulation and Eggs
• Coagulation begins at 140 F
– egg proteins begin to form web and begin to
scramble
– good when you want scrambled eggs
– bad when you’re using eggs to thicken a sauce
or custard
Functions of Eggs in Cooking
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Main Ingredient
Thickening Agent
Leavening Agent
Emulsifying Agent
Binding Agent
Coating Agent
Main Ingredient
How prepared:
• Usually done on stove,
sometimes in oven
Examples:
• Omelets, Scrambled
Eggs, Poached Eggs
Thickening Agent: Ice Cream,
Crème Brulee, Flan (Custards)
• Eggs are heated in liquid
• Coagulation of eggs cause liquid
mixture to thicken or set
– Must be cooked gently or Else Scrambled
Eggs
Foods that use eggs to
thicken their liquid
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Flan
Crème Brulee
Pumpkin Pie
Pudding
Custard
Ice cream
Eggs Function as Leavening
Agent
How?
• High Protein traps steam
and creates rise
Did you know?
Eggs whites can be whipped
up to 8 times their original
volume
Examples:
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Soufflés
Angel Food Cake
Popovers
German Pancakes
Eggs function as
Emulsifying Agent
Emulsify
• Helps to combine 2 liquids
that normally will not
combine and stay
combined
– Example: Vinegar & Oil
– Lemon Juice & Oil
Examples
• Mayonnaise
• salad dressing
• hollandaise sauce
Note about emulsifications
• Emulsions must be blended slowly or
emulsion will “break”
– Break: Fats separate from non-fats
Emulsified Hollandaise
Broken Hollandaise
Eggs Act as Binding Agent
What this means:
• Helps a mixture stick
(BIND) together
Examples
• Meatballs
• Meatloaf
• Ricotta cheese in lasagna
EGGS as Coating Agent
What?
• Food is dipped in egg and
other coating stick to it
– Breadcrumbs
– Panko
– Cornflakes
Examples
• Chicken fingers
• Fish sticks
• Tonkatsu (Japanese breaded
pork chop)
Safety and Sanitation
• Eggs can carry Salmonella
• Most dangerous part of egg is the outer egg shell
• Toss
– cracked or broken eggs
• Pregnant women, elderly, children, etc should not eat
– Eggs sunny side up
– Hollandaise sauce
• Undercooked= less than 160F
Where you might be
undercooked/ raw eggs
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Caesar Salad
Sunny side up eggs
Hollandaise Sauce (for Eggs Benedict)
Home made mayonnaise
Lemon Meringue Pie
• COOKIE DOUGH!
How to avoid safety problems
• Buy Pasteurized Eggs
• Coddle your eggs
– Dip eggs in boiling water
– submerge for 20 seconds
– rinse in cold water to stop cooking