Impacts Of Cooking Methods On Nutrition

Question 1

Boiling

Answer 1

• Up to 50% of vitamin C is damaged when green vegetables are boiled in water
• Vitamins B1, B2 and B3 are damaged by heat and also dissolve in the water
• Some calcium and sodium dissolves in the water that food is boiled in
• Starch (carbohydrate) is gelatinised when cooked in a liquid, which makes it easier for the body to use

Question 2

Steaming

Answer 2

• Steaming is the best method for conserving vitamin C, as only about 15% is lost because the food does not come into direct contact with the boiling water

Question 3

Stir frying

Answer 3

• The fat used in stir frying increases the amount of vitamin A the body can absorb from some vegetables
• The heat will damage vitamin C and some B vitamins, but as they are only cooked for a short time, the damage is minimal

Question 4

Deep fat frying

Answer 4

• The high heat will damage vitamin C and some B vitamins, and can lead to over-coagulation of proteins if cooked for too long
• If the oil is not hot enough when the foods are added, they will absorb oil, which will significantly increase their fat content and energy value

Question 5

All cooking methods

Answer 5

• Protein is denatured and coagulated by heat, which makes it easier for the body to use it
• Protein can be overcooked, which will make it harder and more difficult for the body to use it
• Fat/oil is damaged by repeatedly being heated to fry foods, and it breaks down into substances that are harmful to the body