All cooking methods involve heat. The heat must be transferred from the heat source to the food. This can be done by conduction, convection and radiation.
Method Conduction How it happens
• Transfer of heat from one molecule to another by vibration.
• The food being heated must be in direct contact with the heat source, e.g. heat passing from the cooker hob through the base of the saucepan into the food.
Convection
• Molecules near heat source become hotter and less dense, and rise up.
• This allows cold molecules to take their place.
• This sets up convection currents and heat is spread through liquids and gases.
• This movement of hot and cold gas/ liquid creates an even temperature in the oven or saucepan.
Radiation
• Heat passes in straight rays from the source to the first solid object they reach, without heating air in between.
• The food needs to be as close as possible to the heat rays.
Cooking methods Cooking methods can be divided into groups.
Did You Know? Most cooking methods involve more than one method of heat transfer, e.g. boiling involves conduction (heating of the saucepan) and convection (heating the water and food), and grilling involves radiation (heating the surface molecules) and conduction (heating the food molecules).
