Heat Transfer

Question 1

Conduction

Answer 1

Transferred through direct contact

Stoves that conduct heat through the pan to the food

Question 2

Convection

Answer 2

Heat from one place to another by the movement of fluid or gas

Mechanical- whisking a sauce or a fan oven
Normal- less dense, heat rises, cool sinks and is heated

Question 3

Radiation

Answer 3

Electro magnetic waves go through air (infrared or microwaves)

Used In microwaves or the grill

Question 4

Boiling

Answer 4

Boiling, simmering and poaching use water in cooking

Poaching: under 82c
Simmering: 85-93c
Boiling: 100c

Question 5

Heat damage

Answer 5

50% Vit C is damaged in boiling
Vit B is heat damaged and dissolved in water
Starch is gelatinised

Question 6

Steaming benefits

Answer 6

Save Vit c as food is not submerged

Question 7

Baking

Answer 7

Uses dry heat
High temp can overcook proteins
Damaged Vits B + C

Question 8

Roasting

Answer 8

Dry heat
Refers to meat + veg whereas baking is for breads and cakes
High heat damages B+C

Question 9

Grilling

Answer 9

Dry heat
Heat from above
Damages B Vits
Overcooks protein

Question 10

Stir frying

Answer 10

Food is cooked in a saucepan with a small amount of fat at high heat for very little time
Heat damage is less because of the short time
Fat increases Vit a absorption

Question 11

Microorganisms

Answer 11

Bacteria in yogurt make lactic acid
Cheese uses mound (+rennet)
Yeast in alcohol and bread
Mound in chorizo and salami