Cooking Methods and Food Science: notes

Why cook

• Reasons: kill germs, make food soft, improve taste and make it easier to digest.

Heat transfer

• Conduction: heat passes through a pan. Convection: hot liquid or air moves around. Radiation: heat travels as rays, for example a grill.

Methods

• Boiling and steaming: moist, no added fat. Frying: hot oil, crisp food. Baking: dry heat in an oven.

Food science

• Gelatinisation: starch grains swell and thicken a liquid when heated, as in porridge.
• Protein: sets (coagulates) when heated, as an egg does.
• Raising agents: yeast gives carbon dioxide; baking powder reacts with liquid and heat; whisking traps air.
• Nutrient loss: vitamin C is lost in long boiling.