How Is the Energy Content of Foods Determined in the Laboratory?

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The energy content of foods is determined using a bomb calorimeter, where the food is combusted to measure the heat released. During the process, the temperature change of water in the calorimeter is recorded. For example, burning a peanut may result in a temperature increase of 6.0°C with 100.0g of water, leading to a calculated energy release of 2508J. This value is then converted to calories by dividing by 4.184J, resulting in approximately 599.43 calories for the peanut. Accurate unit management is crucial in these calculations.
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Explain the laboratory methods used to determine the energy content of foods?
The laboratory methods used to determine the energy content of foods would be to combust it in a bomb calorimeter. Let’s say that I wanted to see how much calories is in a peanut. What I would do is burn it in a bomb calorimeter. As I am burning it, I would record the temperature of the water inside the bomb calorimeter. After the peanut is completely burned, I would calculate the Q value of water. Let's the temperature changed 6.0 oC and the mass of water was 100.0g. I calculate Q by (6.0 oC)(100.0g)(4.18kJ/ oC), which is 2508J. I would divide that with 4.184J because 1cal=4.184J. The calories in that peanut would be 599.43 cal.
 
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Looks right to me. Just take care on your units, the units of specific heat are KJ/ (kg K) don't forget the mass unit.

Regards,
-Hoot
 
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