The measurement of the calorie value of foodstuffs or the energy expenditure of a person. In direct calorimetry, a small measure of food is burned up inside a sealed container, which is immersed in water. The rise in water temperature that results is used to calculate the calorie value. Energy production in humans is measured by oxygen uptake. Every litre of oxygen taken into the body produces 4.8 kilocalories of energy. Energy production is calculated by comparing the percentage of oxygen in air inhaled and exhaled.
Calorimetry |
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