Caloric Content of Food
Chelsey Grasham
Lab Report Assistant
Purpose: The purpose of this experiment was to compare the calorie content of certain foods after finding the energy capacity of those foods. Also, a purpose of this experiment was to learn what calories really are.
Procedure: In this experiment, I weighed foods, made my own calorimeter to find the actual weight of the food, after I calculated the temp. of the water. I did this for the chip, pistachio, and marshmallow.
Conclusion: In conclusion, this experiment taught me how to effectively measure calories, compare calories between foods, and overall see how calories and certain foods affect the human body.
Exercise 1: Determination of Caloric Content of Three Foods
Data Table 1. Mass (g) of the Water.
Nut
Marshmallow
Chip
Mass of the water
45.8
44.7
49.2
Data Table 2. Caloric Calculations.
Food Item Description:
Nut (Type: green pistachio)
Marshmallow (Jumbo)
Other Sample (Chip)
Mass of food, cup, and clamp – initial
29.1 g
34.1 g
29.6 g
Mass of food, cup, and clamp – final
28.9 g
33.6 g
29.3 g
Mass of burned food
0.2 g
0.5 g
0.25 g
Observations of the Flame (intensity, length of time burning, etc.)
The pistachio caught on fire really quickly and it burned for a couple minutes
The marshmallow caught on fire and turned black but it only burned for maybe 8 seconds
The chip caught on fire quickly and burned for about 60 seconds with a small flame
Water temp – initial (°C)
31.0
28.1
31.1
Water temp – final (°C)
35.6
32.2
35.2
Change in temp (ΔT) (°C)
4.6
4.1
4.0
(Q) Energy Released (kcal/g)
1.2 kcal/g
0.35 kcal/g
0.8 kcal/g
Energy Estimated on Package (kcal/g)
5.7 kcal/g
1.7 kcal/g
5.4 kcal/g
Percent Difference
81%
80%
85%
Determination of Calories according to Atwater Factors (kcal/g)
6.1 kcal/g
3.3 kcal/g
5.5 kcal/g
Questions:
A. Compare the calorimeter that you built to a bomb calorimeter. How are they similar and different?
Similar: constant volume and temperature
Different: caught fire outside of water, not enclosed, no stirring of water
B. Based on your results, was this setup a good way to measure Calories as opposed to a bomb calorimeter? What types of experimental error may have occurred with this experiment? How might you design this setup differently if you had unlimited expenses for materials? I thought this way a fairly simple at home way to measure calories as opposed to bomb colorimeters which are harder to make than the one I made. An error that I think occurred was that the heat started to come out of the tent so the heat started to become lost. If I had unlimited expenses I would probably try to recreate a real calorime