1. 4.4 b The performance Characteristics of eggs (p 115)
Coagulation (Denaturation)
Peptide bonds between amino acids broken
Permanent change
3D network – water trapped
Heat, acid or mechanical
Egg white coagulates 60-65°C
Egg yolk 65-70°C
Over cooking = syneresis
Bain Marie protects overheating
Acid firmer set, sugar looser
1 egg sets 250ml milk
More yolk – firmer set

2. Foam Gas in a liquid – air through egg white
Ovalbumin stretches & holds air
Proteins denatured – uncurl
3D air / liquid structure = stable
Salt - lower pH resists foaming
Sugar – interferes with bonds more whisking
Fat – (inc egg yolk) won’t foam
Alkalis – increases pH less time to foam
Acids – softens foam
Egg yolk foam – Swiss roll – over steam – mechanical & heat

3. Emulsification
Emulsion = one liquid dispersed in small droplets into another liquid (doesn’t naturally mix)
e.g. milk, salad dressing, mayonnaise
Emulsifying agent needed
Egg yolk – holds fat in emulsion
Lecithin in yolk – hydrophobic & hydrophilic components = suspension
Creamed cake mixture = fat in sugar emulsion

4. Eggs also . . . Colours & enriches – nutrition &
colour through carotene (vit A)
Flavours –Baked products due to fat content

5. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Beating = incorporating air into a mixture
Creaming method = Sugar & fat creamed = air in fat
foam. Abrasive action of sugar
separates fat & traps air

6. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Whisking - Adding air – denatured = mechanical & some coagulation as heat produced
Shortening – fat = crumbly texture. Particles coated with fat = waterproof barrier. Reduces
gluten formation. Also traps air

7. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Kneading = adds strength to dough. Gliadin & Glutenin = proteins = gluten when kneaded. Structure of bread – holds pockets of Co2. Produces springy, elastic dough

8. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Heating = cooking food = chemical & physical changes
Melting method = sugar & fat melted other ingredients added. Bicarbonate of soda released Co2 = soapy taste masked by spices

9. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Moist heat on Carbohydrates = starch grains soften & absorb liquid = gelatinisation 75-87°C. Sauce making
Roux sauce All in one
Blended method

10. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Dry heat on Carbohydrates = non enzymic browning
Maillard reaction – proteins (amino acids) & starch (maltose) = brown colour. Starch – dextrin = dextrinisation = brown crust
Caramelisation = oxidation of sugars - sucrose

11. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
Heat on proteins = denatured. Permanent change = coagulation
Heat on fat = solid fat melts – assists with gelatinisation
Over heating = break down to glycerol & fatty acids

12. 4.4 c Behaviour Changes (bread, cakes, sauces & pastry) (p123)
What happens in the oven?
Creamed cake – Self raising flour, margarine/butter, caster sugar, eggs
Whisked sponge – plain flour, egg, caster sugar
Pastry – plain flour, lard, margarine & water
Bread – Strong flour, fat, yeast, salt, water