Methods Of Cooking Flashcards
Methods of heat transfer (3)
- conduction
- convection
- radiation
Conduction
Heat travels from the heat source to the food by direct contact. Heat causes the molecules in the cooking utensil (Eg; frying pan) to vibrate more vigorously. These molecules collide with neighbouring molecules, causing them to vibrate more vigorously as well. Through this process, heat is also transferred to the food, which is in direct contact with the frying pan
Food is cooked as heat is continuously transferred from the heat source to the frying pan to the surface of the food to the Centre of the food.
Convection
Heat is transferred by the movement of liquid/gas. As liquid/gas is heated, the hotter portion rises, while the cooler portion sinks, creating a convection current. This current passes energy from the hot liquid/gas to the food. (Eg; oven or boiling water)
Radiation
The transfer of energy from the heat source in the form of rays and waves.
Does not require a medium for heat transfer
Heat transfer occurs when microwaves or infrared rays are emitted. Food absorbs it and gets cooked
Explain how heat is transferred in baking and state the advantages & disadvantages of it
Conduction from baking tray
Convection from convection currents within the oven
Radiation from the heat source
Sometimes, oven fans are turned on to increase the rate of heat transfer, reducing cooking time.
Advantages;
- more food can be baked at the same time
- healthier cooking method as little/no oil is used
- development of colour, flavour & texture due to browning reactions at high temperatures
Disadvantages;
- relatively long cooking time
- loss of B group & C vitamins
- high energy consumption
Explain how heat is transferred in grilling and state the advantages & disadvantages of it
Huge amounts of Radiation by infrared waves is the primary form of heat transfer
Convection also contributes some heat
Advantages;
- quick cooking method
- low-fat cooking method
- development of colour, flavour & texture due to browning reactions at high temperatures
Disadvantages;
- need for constant attention to prevent food from charring
- loss of B group & C vitamins
- risk of forming carcinogenic compounds on grilled food
Explain how heat is transferred in dry/stir frying / sautéing and state the advantages & disadvantages of it
Conduction is the main form of heat transfer in dry frying
Advantages;
- quick cooking methods
- development of golden brown colour, flavour & texture due to browning reactions at high temperatures
- reduced loss of nutrients
- healthier cooking method as little/no oil is used
Disadvantages;
- constant attention required during cooking to prevent the food from charring
- low-fat food is unsuitable to be cooked using dry-frying
- very delicate food is unsuitable to be cooked using stir frying
Explain how heat is transferred in shallow frying and state the advantages & disadvantages of it
Heat is transferred via conduction from the hot pan to the food
Advantages;
- quick cooking method
- development of golden brown colour, flavour & texture due to browning reactions at high temperatures
Disadvantages;
- constant attention required during cooking to prevent the food from charring
- loss of B group & C vitamins than stir-frying/sautéing
- possibility of accidents as the oil used for frying is very hot
Explain how heat is transferred in deep-frying and state the advantages & disadvantages of it
Convection is the main form of heat transfer during deep frying
Advantages;
- quick cooking method
- development of golden brown colour, flavour & texture due to browning reactions at high temperatures
Disadvantages;
- constant attention required to prevent the food from charring
- loss of B group & C vitamins compared to stir-frying/sautéing
- possibility of accidents as the oil used for frying is very hot
- a large amount of oil is needed in deep frying, thus increasing the fat content of food significantly
Explain how heat is transferred in boiling and state the advantages & disadvantages of it
Convection is the main form of heat transfer.
Advantages;
- quick & easy method
- softening of food
- healthier cooking method as little/no oil is used
Disadvantages;
- loss of shape & colour of delicate food as a result of excessive boiling
- loss of water-soluble group vitamins (B group & C)
Explain how heat is transferred in simmering and state the advantages & disadvantages of it
Convection is the main form of heat transfer
Advantages;
- softening of food
- healthier cooking method as little/no oil is used
Disadvantages;
- relatively longer cooking time comparing to boiling
- loss of water soluble vitamins (B group & C)
Explain how heat is transferred in steaming and state the advantages & disadvantages of it
Convection is the main form of heat transfer in steaming
Advantages;
- softening of food
- healthier cooking method as little/no oil is used & the conservation of most nutrients
- retention of original food flavour
- a few dishes can be cooked at the same time with a tiered steame, hence saving fuel
Disadvantages;
- requires the longest cooking time among all moist heat cooking methods & is not suitable for tough meat
- requires attention to prevent water in the steamer from drying out
Explain how heat is transferred in microwave cooking and state the advantages & disadvantages of it
Radiation is the main form of heat transfer in the microwave. The microwave produces a type of electromagnetic wave that can penetrate food. As microwaves are able to vibrate water molecules more vigorously producing heat, food can be heated up directly & quickly
Advantages;
- quick & healthier cooking method with low heat, so most nutrients can be conserved
- ease of use
- suitable for reheating food & quick thawing of frozen food
Disadvantages;
- difficulty in controlling doneness, & possibility of a drier texture
- greater moisture loss compared to stir-frying/sautéing
- possibility of large pieces of food being heated up unevenly, leaving the centre of the food cold or uncooked
