1.    The independent variable for this science fair project is the type of processed chicken meat – fresh, frozen and irradiated. The dependent variable is the size of the bacteria growth in the Petri dish. This is determined by measuring the size of the bacteria growth using a ruler. The constants (control variables) are room temperature, the amount of sunlight and the ingredients in the Petri dish agar.

2.    Prepare  3 Petri dishes  using agar and store them in a refrigerator. The Petri dishes are brought to room temperature before the start of experiment by taking them out of the refrigerator. Label the Petri dishes “Fresh”, “Frozen” and “Irradiated”.

3.    Label the 3 beakers as “Fresh”, “Frozen” and “Irradiated” as well. Using separate knives and chopping boards to prevent cross contamination, an equal portion of the fresh, frozen and irradiated chicken parts are cut and placed into the respective labeled beaker. Expose the outer surface of the  meat as this is where the bacteria will be found.

4.    Pour 100ml of disinfected water into each  beaker and soak the meat for 10 minutes.

5.    Wet the swab with sterilized water. Dip the swab inside the beaker. Swipe the swab over the respective agar surface according to the label on the beaker and Petri dish.  Close the cover and keep the Petri dish in a cool shaded place for the bacteria to grow.

6.    Measure The diameter of the bacteria colony growth after 5 days and recorded it in the table provided below.