Keep three quantities separate: the ingredients in the recipe, the weight of the finished batch, and the weight of your portion. The portion’s share of the batch gives you the same share of the recipe’s calculated nutrition, under the assumption that the portion has the same composition as the batch.
In CORPUS, you can build reusable Recipes from pantry foods, USDA entries, label scans, or manual entries. Set the finished recipe weight to calculate nutrition for the full batch and per 100 g. [1]
Start with a batch you can account for
Use a simple mixed dish for your first record. Before assembling it, list the ingredients and the amounts used. Keep a note of any ingredient you leave out or replace. The purpose is to make the saved recipe describe this batch, rather than an older version with the same name.
Record the ingredients and quantities used in the batch. Check each food entry against its source.
Find the weight of the finished food alone. If the food stays in a vessel, subtract the empty vessel’s weight from the combined weight. Use a scale and vessel suitable for the task.
Set that finished food weight in the Recipe and review the full-batch and per-100 g figures.
Weigh the portion separately. Use its fraction of the finished batch to check the calculated amount.
A worked example
This example uses an imaginary batch and invented nutrient totals. The portion size illustrates the calculation; it is not a recommendation.
Suppose an empty container weighs 400 g. With the finished food inside, it weighs 1,600 g. The food alone weighs 1,200 g. Suppose the recipe’s ingredient entries add up to an estimated 2,000 kcal and 100 g of protein. You serve 300 g of the finished food.
One hypothetical batch, three useful views
View | Calculation | Calculated result |
|---|---|---|
Finished food weight | 1,600 g − 400 g | 1,200 g |
Portion share | 300 g ÷ 1,200 g | 0.25 of the batch |
Energy in the portion | 2,000 kcal × 0.25 | 500 kcal |
Protein in the portion | 100 g × 0.25 | 25 g |
Energy per 100 g | 2,000 kcal ÷ 1,200 g × 100 g | About 166.7 kcal |
Protein per 100 g | 100 g ÷ 1,200 g × 100 g | About 8.3 g |
The full-batch calculation is a useful cross-check: 300 g is one quarter of 1,200 g, so its calculated values are one quarter of the batch totals. Use the unrounded batch values when checking the arithmetic; a rounded per-100 g display can introduce a small difference.
Make the assumptions visible
A gram-based allocation assumes each portion resembles the batch as a whole. If one plate receives mostly one ingredient and another receives mostly a different ingredient, equal weights alone do not establish equal composition. Keep separately portioned components separate in your record when that better describes what happened.
The example also assumes the ingredient totals represent the food that remains in the finished batch. If you discard part of an ingredient or a sauce, simply weighing the remainder does not tell you the nutrition of what was discarded. Note that limitation instead of treating the calculation as an analysis of the finished food.
If a later batch weighs 1,000 g but has the same assumed totals, a 300 g portion is 30% of that batch: 600 kcal and 30 g of protein in this hypothetical calculation. That is why the finished weight belongs to the batch you made. Do not carry an old weight forward without checking it.
What to keep for next time
Keep the ingredient version, finished weight, and portion weight together. The scale gives you a weight; the nutrient total still depends on the ingredient data and how the food is divided. Keeping both in view makes the result easier to check next time.
If you make the same dishes often, explore CORPUS Recipes in the App Store. You can also check current device requirements there. [1]
Sources & further reading
CORPUS App Store listing and version history. Accessed 2026-09-28.
Drafted with AI assistance and checked in a separate automated editorial review. This article has not received human or medical review. Our editorial standards.