CH 4 ENERGY VALUE OF FOOD

Question 1

what is the value of 1 kcal?

Answer 1

1kcal = quantity of heat needed to raise temp of 1kg of H20 at 1 degree C

Question 2

what is direct calorimetry?

Answer 2

burning food in a bomb calorimeter

Question 3

what are the average gross energy values of the macronutrients?

Answer 3

CHO: 4.2 kcal/g

lipid: 9.4 kcal/g
protein: 5.65 kcal/g

Question 4

what is net energy?

Answer 4

energy available to the body

Question 5

what is the difference between gross and net energy?

Answer 5

gross: energy value of foods determined by direct calorimetry
net: quantity of energy that can be used by the body from food

Question 6

coefficient of digestibility (definition)

Answer 6

proportion of food consumed that is digested and is absorbed

Question 7

what is the avg. coefficient of digestibility for each macronutrient?

Answer 7

CHO: 97%

lipid: 95%
protein: 92%

Question 8

what are Atwater General Factors?

Answer 8

provide useful estimate of the net energy value of typical foods a person consumes

Question 9

what are the average Atwater values?

Answer 9

CHO: 4kcal/g

lipid: 9kcal/g
protein: 4kcal/g
alcohol: 7kcal/g