Practical Engineering Challenge with Apples
Why do apples turn brown?
Oxidation is a process in which oxygen binds to the molecules of the apple. As this happens the flesh of the apple turns brown and a little mushy. In order to prevent this process you can bind something else to the flesh of the apple, which is what the restaurants do. The down side is that the flavor of the apple is distorted. Another possible solution is to protect the flesh of the apple from the air. This is the challenge for your child.
For this experiment you will need apple slices and whatever your child chooses to make a skin to help the apple not turn brown such as: plastic, foil, and cheese.
Control and experimental variables
When testing your child’s solutions be sure to compare against an apple slice that is open to the air. This is known as the control group. By watching the control apple slice turn brown, you can decide when you should evaluate the effectiveness of your strategies. The various skins are the experimental variables, and the apples wearing them are the experimental groups.
Science as a cyclical process
If your child finds something that seems to work, discuss how the solution could be improved. Try again. One of the things that experts are really emphasizing right now is the importance of seeing the
scientific process as cyclical. Go through a set of trials, analyze your results, then go through another set of trials.
Who knows, your child may come up with the solution we are all using to pack lunches five years from now!