Chapter 41, Problem 1TYK

Summary Introduction

To analyze:

The caloric content of whole milk and skim milk.

Introduction:

The milk consists of proteins, fatty acids, vitamins, energy compounds, inorganic elements, and water. Skim milk is the type of milk from which all the cream or milk fats have been removed. However, whole milk is the normal type of milk, which contains the proper amount of fat content. Skim milk contains 12 g (gram) carbohydrates and 8 g protein. Whole milk contains 12 g carbohydrates, 8 g protein, and 8 g fat.

Explanation of Solution

The calorie content of food is the amount of energy contained in a particular food. The calorie content is measured in kilocalories (kcal). The energy provided by fats is 9 kcal/g, and the energy provided by carbohydrates and proteins is 4 kcal/g each.

The caloric content of skim milk containing 12 g carbohydrates and 8 g protein can be calculated as follows:

$\begin{array}{c}1\text{ g carbohydrate}=\text{4 kcal/g}\\ \text{12 g carbohydrates}=\text{12}\times \text{4 kcal/g}\\ =\text{48 kcal/g}\end{array}$

Similarly,

$\begin{array}{c}1\text{ g protein}=\text{4 kcal/g}\\ \text{8 g protein}=\text{8}\times \text{4 kcal/g}\\ =\text{32 kcal/g}\end{array}$

Therefore, the total caloric content of skim milk is $\text{48 kcal/g}+\text{32 kcal/g}=8\text{0 kcal/g}$.

The caloric content of whole milk containing 12 g carbohydrates, 8 g protein, and 8 g fat can be calculated as follows:

$\begin{array}{c}1\text{ g carbohydrate}=\text{4 kcal/g}\\ \text{12 g carbohydrates}=\text{12}\times \text{4 kcal/g}\\ =\text{48 kcal/g}\end{array}$

Similarly,

$\begin{array}{c}1\text{ g protein}=\text{4 kcal/g}\\ \text{8 g protein}=\text{8}\times \text{4 kcal/g}\\ =\text{32 kcal/g}\end{array}$

and

$\begin{array}{c}\text{1 g fat}=\text{9 kcal/g}\\ \text{8 g fat}=\text{8}\times \text{9 kcal/g}\\ =\text{72 kcal/g}\end{array}$

Therefore, the total caloric content of whole milk is $\text{48 kcal/g}+\text{32 kcal/g}+\text{72 kcal/g}=\text{152 kcal/g}$.

Conclusion

One serving of skim milk has approximately 80 kilocalories (kcal), while one serving of whole milk has about 152 kcal. The carbohydrates and proteins provide 4 kcal per gram (kcal/g), whereas fats provide 9 kcal/g.