The Kilojoule is a unit of measure of energy or work. Knowing that each kilocalorie equals 4.1868 kilojoules, it is relatively easy to convert from one unit to another. One kilojoule equals 1000 joules. This unit of measurement was created by the English James Prescott Joule, who through his experiences sought to find the relationship between heat and energy. This scientist created an experience that became famous, for being able to relate the energy produced by a falling body, by heating the water contained in a container. It was he who established through this and other experiences the equivalence between calorie and joule, in which we have the mechanical energy to be converted into thermal energy.
The Kilocalorie is a unit of energy measurement. The kilocaloric unit is generally used to measure the amount of energy in food. This term represents 1000 calories, which is the unit used in food labels. Those who follow diets often need to account for the amount of calories consumed. But how has the unit of caloric measurement been established? It is very easy, it was agreed that a calorie is equivalent to the amount of heat or energy needed to raise 1ºC the temperature of 1 gram of water. When we refer to food, Kilocalorie is the amount of energy supplied by them, if they are fully utilized by the body. One way to measure calories is to use a device called a calorimeter, which measures the amount of heat released when the food is burned! Food labels sometimes refer to calories, when in fact there should be kilocalories. For example, a glass of juice does not have about 200 cal. but 200 kcal.