Summary

Carbohydrates, fats and proteins are required in relatively large amounts in our diets and provide most of the energy required to our bodies. The total amount of energy made available when food is metabolised depends on the combination of nutrients the food contains.

Energy in food can be determined using a calorimeter. The basic principle of calorimetry is that the energy produced during combustion of food is absorbed by a known amount of water and thus increases its temperature.

In this experiment you used a simple calorimeter to compare the heat energy from burning different types of food. The change in the temperature of water during combustion was measured using a temperature probe and it is a direct measure of the food energy content. A crucible containing the food was weighed before and after the combustion to calculate the mass of food burned to heat the water. The experimental number of calories per gram in different foods was calculated and compared to nutritional information on food labelling.

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