How this calculation works
Overrun compares the product’s expanded volume with the original mix volume. Equal-volume samples allow that expansion to be inferred from their different masses, provided the samples represent comparable base material and packing.
Overrun % = (equal-volume mix mass/product mass − 1) × 100; final air fraction = 1 − product mass/mix massA worked example
A 100 mL cup containing 120 g mix and 80 g product gives a mass ratio of 1.5. Apparent overrun is fifty percent, while final air-volume fraction is one-third. Ten litres of mix then gives an estimated fifteen litres of aerated product. At 100 mL per entered portion, that is 150 whole portions under the model.
Good to know
Equal-volume apparent expansion only; no legal product category, quality target, nutrition, composition change or frozen density correction. Use representative, consistently filled samples. The calculation cannot distinguish incorporated air from large sampling voids or other changes in density.
Reference: University of Guelph — overrun calculations (opens in a new tab) ↗
What this calculation answers
Overrun compares the product’s expanded volume with the original mix volume. Equal-volume samples allow that expansion to be inferred from their different masses, provided the samples represent comparable base material and packing.
The apparent air fraction uses final product volume as denominator. It is therefore different from overrun, which uses original mix volume. A fifty-percent overrun does not mean half the final container is air.
The Water freezing energy and time calculator includes latent heat during a phase change. An overrun measurement is a volume-density comparison and does not supply that cooling load.
Use the right input conventions
Subtract the cup tare from both weights and fill the same volume for each sample. A loose scoop with large voids or a cup packed differently can distort the apparent product density.
Batch volume refers to the unaerated mix. Portion volume is a user-chosen serving-volume unit, not a recommended serving size or a nutrition calculation. The model assumes the measured expansion represents the whole batch.
Interpret the result
The density table divides each net sample weight by the common cup volume. If equal-volume product weighs more than mix, the inferred overrun would be negative; this aeration model rejects that case.
The final batch volume is divided into whole entered-volume portions, with the remainder shown. Volume expansion is not a legal composition test or a universal measure of product quality, and freezing itself can also affect apparent density.
Work through the example
A 100 mL cup containing 120 g mix and 80 g product gives a mass ratio of 1.5. Apparent overrun is fifty percent, while final air-volume fraction is one-third.
Ten litres of mix then gives an estimated fifteen litres of aerated product. At 100 mL per entered portion, that is 150 whole portions under the model.
Where the model stops
Equal-volume apparent expansion only; no legal product category, quality target, nutrition, composition change or frozen density correction.
Use representative, consistently filled samples. The calculation cannot distinguish incorporated air from large sampling voids or other changes in density.
A few questions, answered
Why are overrun and air fraction different?
They divide the extra volume by different denominators: original mix versus final product.
Must the sample cup weights include the cup?
No. Use net content weights after subtracting tare.