What is the stated average nitrogen content of protein?

What is the stated average nitrogen content of protein?

• A. 12%
• B. 20%
• C. 16%
• D. 24%

Answer: (C)

Protein contains nitrogen in its amino groups, and when averaged across all amino acids, nitrogen makes up about 16 percent of protein by weight. This standard figure is used in nutrition to estimate protein content from nitrogen measurements: since 100 grams of protein contain roughly 16 grams of nitrogen, the protein amount is obtained by multiplying the nitrogen amount by about 6.25 (100 ÷ 16 ≈ 6.25). In practice, some foods can vary slightly, typically around 15–17%, but 16% is the conventional stated average used for calculations and labeling.

Protein contains nitrogen in its amino groups, and when averaged across all amino acids, nitrogen makes up about 16 percent of protein by weight. This standard figure is used in nutrition to estimate protein content from nitrogen measurements: since 100 grams of protein contain roughly 16 grams of nitrogen, the protein amount is obtained by multiplying the nitrogen amount by about 6.25 (100 ÷ 16 ≈ 6.25). In practice, some foods can vary slightly, typically around 15–17%, but 16% is the conventional stated average used for calculations and labeling.