Protein and carbohydrates provide$\mathbf{4}\mathbf{.}\mathbf{0}\mathbf{Cal}\mathbf{/}\mathbf{g}$, whereas fat gives $\mathbf{9}\mathbf{.}\mathbf{0}\mathbf{Cal}\mathbf{/}\mathbf{g}$. (Remember that 1 Calorie , with a capital C, is really $\mathbf{1}\mathbf{kcal}$.) The weight percentages of these components in some foods are

Calculate the number of calories per gram and calories per ounce in each of these foods. (Use Table 1-4to convert grams into ounces, remembering that there are 16ounces in 1pound.)

The amount of heat necessary to increase the temperature of one gram of water by one degree Celsius at a pressure of one atmosphere, which is equivalent to around 4.19 joules is oxidized in the body, a unit corresponding to the big calorie representing the heat-producing or energy-producing value in food an amount of food with an energy-producing value of one large calorie.

Protein and carbs are widely known to offer $4Cal/mg$, whereas fat provides $9Cal/mg$. Here's a table with the weight percentages of various ingredients in several foods, so figure out how many calories are in each gram and per serving.

From Table 1-4 we can see that$1g=0.0353$ ounce so we can calculate the following with:

$$\begin{gathered} \mathbf{Cal}\mathbf{/}\mathbf{g}=(\mathbf{wt}\%/100(\mathbf{}\mathbf{protein})\times 4\mathbf{Cal}\mathbf{/}\mathbf{g})+(\mathbf{wt}\%/100(\mathbf{}\mathbf{carbohydrate})\times 4\mathbf{Cal}\mathbf{/}\mathbf{g})+(\mathbf{wt}\%/100(\mathbf{fat})\times 9\mathbf{Cal}\mathbf{/}\mathbf{g}) \\ Cal/ounce=\mathbf{Cal}\mathbf{/}\mathbf{g}\times 1/0.0353 \end{gathered}$$

1. Shredded wheat:

-calories per gram: $(0.099\times 4\mathbf{Cal}\mathbf{/}\mathbf{g})+(0.79\times 4\mathbf{Cal}\mathbf{/}\mathbf{g})=3.556\mathbf{Cal}\mathbf{/}\mathbf{g}$

-calories per ounce:$3.556\mathbf{Cal}\mathbf{/}\mathbf{g}\times 1/0.0353=100.74\mathbf{Cal}\mathbf{/}\mathrm{ounce}$

2. Doughnut:

-calories per gram: $(0.046\times 4\mathbf{Cal}\mathbf{/}\mathbf{g})+(0.514\times 4\mathbf{Cal}\mathbf{/}\mathbf{g}\mathbf{)}+(0.186\times 9\mathbf{Cal}\mathbf{/}\mathbf{g})=3.914\mathbf{Cal}\mathbf{/}\mathbf{g}$

-calories per ounce:$3.914\mathbf{Cal}\mathbf{/}\mathbf{g}\times 1/0.0353=110.88\mathbf{Cal}/ounce$

3. Hamburger:

-calories per gram:$(0.242\times 4\mathbf{Cal}\mathbf{/}\mathbf{g}\mathbf{)}+(0.203\times 9\mathbf{Cal}\mathbf{/}\mathbf{g})=2.795\mathbf{Cal}\mathbf{/}\mathbf{g}$

-calories per ounce:$2.795\mathbf{Cal}\mathbf{/}\mathbf{g}\times 1/0.0353=79.18\mathbf{Cal}/ounce$

4. Apple:

-calories per gram:$(0.12\times 4\mathbf{Cal}\mathbf{/}\mathbf{g})=0.480\mathbf{Cal}\mathbf{/}\mathbf{g}$

-calories per ounce: $0.48\mathbf{Cal}\mathbf{/}\mathbf{g}\times 1/0.0353=13.598\mathbf{Cal}/ounce$