Protein grams and an EU high-protein claim have different denominators

Ten grams of protein per 100 g tells you a protein concentration. It does not by itself settle an EU high-protein claim. That claim uses protein's contribution to the food's energy, so two foods with identical protein concentration can have different calculated energy shares.

Choose a consistent energy calculation

The Annex to Regulation (EC) 1924/2006 sets the high-protein condition at at least 20% of the food's energy coming from protein. Annex XIV of Regulation (EU) 1169/2011 gives protein conversion factors of 4 kcal per gram and 17 kJ per gram.

For a kcal-based worksheet, multiply protein grams by 4, divide by total kcal for the same food quantity, then multiply by 100. If using kJ, use 17 and total kJ instead. Do not mix a kcal numerator with a kJ denominator.

Same protein, different energy share

Take two invented ready-to-eat foods with exact practice values. A contains 10 g protein and 160 kcal per 100 g. B contains 10 g protein and 250 kcal per 100 g.

• A: 10 × 4 = 40 kcal from protein; 40 ÷ 160 × 100 = 25%.
• B: 10 × 4 = 40 kcal from protein; 40 ÷ 250 × 100 = 16%.

On these assumptions, A reaches the 20% numerical threshold and B does not. Both still contain 10 g protein per 100 g. There is no contradiction: one result describes mass concentration and the other describes a share of total energy.

Catch the denominator mistakes

Use the total energy for the exact quantity represented by the protein value. Protein per portion divided by energy per 100 g mixes quantities. Likewise, dividing protein grams directly by total calories does not produce the required energy share because the numerator has not yet been converted into energy.

For a 50 g portion of A, the practice values become 5 g protein and 80 kcal. The calculated share remains 5 × 4 ÷ 80 × 100 = 25%. Changing portion size alone does not change that ratio when both quantities scale together.

Real declarations are rounded, and values near a boundary need appropriate supporting information. Use the food in its relevant prepared state, and do not present this worksheet as a full compliance assessment, protein-quality measurement or personal dietary recommendation.

Download Ingredi AI from the App Store or Google Play to explore its label-reading workflow. When reviewing an explanation, keep the original protein and energy fields available so the denominator can be checked.