Science Project Summary:

Exposure of Baby food and the degree of contamination

Featured science projectScience project video Intermediate 5 < 1 day $10-$25 Readily available [+] More info
Difficulty: Intermediate 5
Cost ($): 20
Time required: < 1 day
1 day to prepare, 3 days for experiment
Availability of materials: Readily available
Easily found
Required Skills: None
Safety concerns:

The bacteria should be destroyed before it is disposed of. Pour some bleach into the petri dish to kill all the bacteria before disposing in the trash.

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This experiment was done to find out if leaving baby food out of the refrigerator after it has been opened will result in bacterial contamination.
Procedure preview:
For this experiment, the independent variable is the type of baby food (chicken vs. pumpkin vs. apple) and the amount of time the food is left out the refrigerator. The dependent variable is the rate of growth of the bacteria colony. This is determined by measuring the size of the colony using a ruler. The constants (control variables) are the room temperature, the brand of each type of baby food, the amount of sunlight exposure and the ingredients used in the preparation of the petri dish agar. The petri dish prepared with the blood agar must be stored in .....