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A saltine cracker has 12 calories What is the process of determining how many calories are in a specific food item?


Look up the instrument called a calorimeter. This is the instrument that is used to determine calories in food items.

Steve Sample

Very simple. You dry it, burn it, and measure the heat given off.

This leads to a somewhat misleading number, because not all components of food that burn are digestible. The more thorough method is to analyze the food item to find how much fat, protein, and digestible carbohydrates it contains, and to convert those amounts to calories.

Richard Barrans Jr., Ph.D.

A device called a bomb calorimeter is used. A piece of the food is put in the chamber, it is sealed and it is ignited and burned. The amount of heat energy it gives off is measured by a thermometer.

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