Introduction and annotated directory

Problem
Hypothesis
Experiment design
Observations and data
Conclusion

Does food color have an affect on celery freshness?

Based on the observations noted in "Celery mystery," we expect the celery in the blue water to say fresh while the celery in the red water wilts.

Overview of procedures:

The students will place one cut celery stock in each of three cups: [1] plan water (our control), [2] water with red food color, and [3] water with blue food color. We will observe the celery after eight days to see if there is a difference between the freshness of the stocks.

Experiment observations can be found here:

Data gallery
Photographs of day 1 and day 8 of experiment.

The students rated the freshness of the celery on a scale of 1 to 5, with 1 being the best. The rating method was subjective, and each group was asked to evaluate freshness based on comparing their 3 celery stocks (control, red food color, blue food color). The class data was collected into a table, then made into a triple bar graph. A computer produced bar graph, made by Katie S., can be seen in the Food color affects celery freshness article in the Student Research Center.

The students concluded that red food coloring seems to age the celery faster while the blue food color keeps it fresher. Also see: Food color affects celery freshness.