Chapter 11, Problem 45Q

(a)

Interpretation Introduction

Interpretation:

The total Calorie content in a slice of the given bread has to be calculated.

Concept introduction:

Macronutrients:

• • They are required in relatively large amounts.
• • Required for the growth, metabolism and other body functions.
• • Calories are included in the compounds containing macronutrients.
• • There will be no toxic effect in their higher concentration.
• • Examples include carbohydrates, proteins and fats.

Explanation of Solution

Given that a slice of whole wheat bread $\left(\text{36}\text{g}\right)$ contains nearly $\text{1}\text{.5}\text{g}\text{fat,}\text{17}\text{g}\text{of}\text{carbohydrate}\left(\text{with}\text{about}\text{1}\text{g}\text{of}\text{sugar}\right)\text{and}\text{3}\text{g}\text{of}\text{protein}\text{.}$

According to the average energy content of macronutrients, one gram of fat contain nine Calorie of energy, one gram of carbohydrate contain four Calorie of energy and one gram of protein contain four Calorie of energy.

The energy content in $\text{1}\text{.5}\text{g}$ of fat is calculated as follows:

$\text{1}\text{.5}\text{g}\text{fat}\text{×}\frac{\text{9}\text{Cal}}{\text{g}\text{fat}}\text{=}\text{13}\text{.5}\text{Calories}\text{from}\text{fat}$

The energy content in $\text{17}\text{g}$ of carbohydrate is calculated as follows:

$\text{17}\text{g}\text{carbohydrate}\text{×}\frac{\text{4}\text{Cal}}{\text{g}\text{carbohydrate}}\text{=}\text{68}\text{Calories}\text{from}\text{carbohydrate}$

The energy content in $\text{3}\text{g}$ of protein is calculated as follows:

$\text{3}\text{g}\text{protein}\text{×}\frac{\text{4}\text{Cal}}{\text{g}\text{protein}}\text{=}\text{12}\text{Calories}\text{from}\text{protein}$

The total number of Calories per slice of bread is calculated as below:

$\text{13}\text{.5}\text{Cal}\text{+}\text{68}\text{Cal}\text{+}\text{12}\text{Cal}\text{=}\text{93}\text{.5}\text{Cal}$

(b)

Interpretation Introduction

Interpretation:

The percent of Calories from fat has to be calculated.

Concept introduction:

Macronutrients:

• • They are required in relatively large amounts.
• • Required for the growth, metabolism and other body functions.
• • Calories are included in the compounds containing macronutrients.
• • There will be no toxic effect in their higher concentration.
• • Examples include carbohydrates, proteins and fats.

Explanation of Solution

Given that a slice of whole wheat bread $\left(\text{36}\text{g}\right)$ contains nearly $\text{1}\text{.5}\text{g}\text{fat,}\text{17}\text{g}\text{of}\text{carbohydrate}\left(\text{with}\text{about}\text{1}\text{g}\text{of}\text{sugar}\right)\text{and}\text{3}\text{g}\text{of}\text{protein}\text{.}$

The energy content in $\text{1}\text{.5}\text{g}$ of fat is calculated as follows:

$\text{1}\text{.5}\text{g}\text{fat}\text{×}\frac{\text{9}\text{Cal}}{\text{g}\text{fat}}\text{=}\text{13}\text{.5}\text{Calories}\text{from}\text{fat}$

The total number of Calories per slice of bread is calculated as below:

$\text{13}\text{.5}\text{Cal}\text{+}\text{68}\text{Cal}\text{+}\text{12}\text{Cal}\text{=}\text{93}\text{.5}\text{Cal}$

The percent Calories from fat is calculated as below:

$\frac{\text{13}\text{.5}\text{Cal}}{\text{93}\text{.5}\text{Cal}}\text{×}\text{100}\text{=}\text{14}\text{.4}\text{\%}$

(c)

Interpretation Introduction

Interpretation:

The reason for considering bread as a highly nutritious food has to be explained.

Concept introduction:

Macronutrients:

• • They are required in relatively large amounts.
• • Required for the growth, metabolism and other body functions.
• • Calories are included in the compounds containing macronutrients.
• • There will be no toxic effect in their higher concentration.
• • Examples include carbohydrates, proteins and fats.

Explanation of Solution

Bread can be considered as a highly nutritious food.

The reason is that one slice of bread equals to have calories of whole grains with some additional calories from sugars and fats.

Therefore, if one slice of bread provides one serving, then a sandwich is considered as two servings.