Question

Energy content of foods is commonly expressed in______​

Answer 1

calories

Food energy is expressed in calories or joules. A calorie is the amount of energy required at one atmosphere of pressure to raise the temperature of 1 g of water from 14.5°C to 15.5°C (NRC, 1981).

Answer 2

kiloJoules (kJ = 103 J)

Calories is not actually used as unit

Because nutritionists and food scientists are concerned with large amounts of energy, they generally use kiloJoules (kJ = 103 J) or megaJoules (MJ = 106 J). For many decades, food energy has been expressed in calories, which is not a coherent unit of thermochemical energy

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