Eggs

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Eggs
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Egg Composition

• Egg components that cooks should know
• Egg white water (90), protein (almost 10)
• Ovalbumin (54 of albumen protein) flavor,
  texture, color of cooked egg sets when heated to
  180oF/80oC
• Ovomucin (1.5 of albumen protein) stabilizes
  foam
• Ovotransferrin (12 of albumen protein) sets
  when heated to 140oF/60oC or foamed
• Egg yolk
• Fat bound to protein-cholesterol-lecithin
  aggregates
• Yolk proteins wont form stable foams
• Color from plant xanthophylls
• Only about 45 water, mostly bound to other
  material

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The Chemistry of Egg Cooking

• Beating an egg unfolding protein into
  water-filled pockets
• Cooking Moderate protein coagulation
• White firms at lower temperature than yolks
• Milk, cream sugar , acid, salt tenderize eggs
• Dilution
• Acid and salt get protein close early, block
  S-S- crosslinking (thicken w/o toughening)

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EggLiquid Mixtures

• Custards
• Mixture of egg and liquid (dont need whites)
• Served in same container as prepared
• Often baked and unstirred
• Sets into a gel
• Creams
• Same mixtures as custards
• Stovetop stirred continuously to pour

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EggLiquid Mixtures

• Preparation of custards
• 1-2 eggs 1 cup liquid with minerals
• Gentle heat
• Always add hot mixture to cold mixture
• Often baked and unstirred, sets into a gel
• Curdling defense starch
• Water bath useful (temp required 185oF/83oC)
• No clinging to toothpicks

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Egg-Liquid Mixtures

• Types of Custard
• Quiche, savory custard
• 1 or more cheese, veggies, meat
• 21 egg liquid (milk in quiche)
• No water bath
• Crust or no crust

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Egg-Liquid Mixtures

• Types of Custard
• Crème caramel and crème brûlée sweet custards
• About 11 egg/cup milk ratio
• Crème caramel
• Caramelized sugar on bottom of baking dish end up
  on top of served custard by inverting
• Bake and chill
• Crème brûlée
• Chill then burn sugar on top

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Egg-Liquid Mixtures

• Types of Custard
• Cheesecake
• 11 egg/cup liquid filling, but more sugar (4
  tbsp/cup)
• Cheese (ricotta, cream cheese)
• Sugar cheese, then eggs flavorings
• No stovetop cooking
• Gentle mixing
• 325oF/163oC
• Water bath helpful
• Cool slowly in open oven

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Egg-Liquid Mixtures

• Creams
• Pourable creams
• Same whole eggmilk ratio as custards (1-2 1)
• Or can be all yolks (up to 4-5/cup milk)
• Scalded milk or cream added to beaten eggs and
  sugar
• Stir constantly (180oF/80oC)
• If fruit purees added, wait until cool
• Stiff creams
• Custard mixture stiffened with flour (1-2
  tbsp/cup liquid)
• Must be boiled and stirred 1 min to kill yolk
  amylase (destroys starch)
• Cool with little stirring

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Egg Foams

• Meringues
• Egg whites only!
• Whip em good!
• Copper bowl blocks S-S- bonds between denatured
  protein, which collapses foam
• Acid blocks S-S- bond formation too
• Avoid yolk, oil, fats, detergent
• Soft peaks to stiff peaks to dry peaks
• Early sugar addition, firmer meringue

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Uses of Egg Foams

• Chocolate mousse a use of meringue
• Mousse base
• Melted chocolate (100oF/38oC)
• Butter
• Raw egg yolks whisked in
• Whipped egg whites
• Stiffly beaten egg whites, 3-4 x volume of base,
  with salt and confectioners sugar
• Fold into base
• Chill

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Folding Technique
Click here for video.
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Uses of Egg Foams

• Soufflés
• Whisk stiff foam
• Lighten liquid base with ¼ to 1/3 egg foam
• Fold slowly into liquid base (except with fruit
  puree or cooked fruit syrup)
• Water bath
• Air expansion with heating (Charles law)
• Starch in base stabilizes foam
• Reheat to rise again

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Egg Yolk Foams

• Yolks need liquid to foam
• Zabaglione and Sabayon
• Equal volumes yolks and sugar, Marsala wine (1-4x
  volume of yolks), water bath heat, whisk to foam
  at 120oF/50oC, stop before solid