This is the amount of energy needed to raise the temperature of one cubic centimetre of water by 1 degree centigrade (⁰C). When talking about food and human energy, the measurement most commonly used is the kilocalorie – 1000 times greater – often written as kcal or calorie. Kilojoule (kJ) is the international unit of energy.
Approximately 4200 joules or 4.2 kilojoules is equal to one kilocalorie.
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