The Difference Between Calories in Foodstuff and Calories in Combustible Material

A combustion calorimeter can be used to measure animal feed. This sounds incomprehensible at first, but it is widely used.

The reason for this is the notion that food calories are not the same as combustible calories. This means that the calories (KJ) written on a food packet are NOT measured in a combustion calorimeter. The food calories are measured by a WET process, which emulates the digestion. The process is lengthy, smelly and messy because the various food groups are separated into the prime food groups such as protein, carbohydrates and fats and then the groups are measured separately.

How is a calorimeter used in food stuff?

In a simple comparative way. If the consistency of a food is more or less the same, then the combustion will give comparative results. Fast! The speed by which the result is obtained is the main reason for using a calorimeter.

Take potato chips: The oil is a major factor in potato chips and can be accurately measured in a combustion calorimeter. It is more or less used as a quality assurance tool.

Take animal feed: It is made of by-products. Which of these increases the weight of the animal the most and which passes through the animal?

For this the intake of animal feed is measured, then the animal's weight gain, and finally the animal excretes.

The combustion calorimeter is used for food and animal feed products, but in a comparative, but very convenient and fast way.