Hobbies And Interests
Ethylene Experiment
One science fair project for fifth-graders involves how bananas ripen while located next to other bananas. This teaches students about the process of how ethylene, a gas byproduct of decomposition, affects the ripening of bananas. All bananas emit the gas and, at different stages of ripening, some emit more than others. This can be demonstrated in the ripening-banana experiment. At the science fair, display a bunch of bananas and a single banana that all have been left out in the air for the same period of time. Include a sheet detailing the scientific method, research, purpose, hypothesis, experiment, and conclusion. Show that ethylene produced by bananas side by side will speed up the ripening process of the other bananas in a bunch.
Benedict's Experiment
Benedict's Experiment shows a fifth-grader how Benedict's solution can determine sugar present in bananas versus vegetables. It's a way to show what foods contain sugar. The chemical composition of a banana will break down when exposed to Benedict's solution. Benedict's solution is composed of copper sulfate, sodium hydroxide, and tartanic acid. It can usually be bought in a hardware store. Place a piece of banana and a few other vegetables in different test tubes and cover with 30ml of Benedict's solution. Heat the test tubes over a burner using tongs. If sugar is present, the solution will turn orange.
Bananas and Yeast
Foods will usually turn moldy after time, but the effects of yeast on foods is difficult to see. This is a great experiment for a science fair because the banana won't actually mold but just be eaten away. Take the inside of two bananas, throw away the skins, and cut the bananas horizontally down the center. Place two of the halves in one plastic bag and the other two halves in another plastic bag. Sprinkle yeast in one of the banana bags and mark it with the letter "Y". Close the bags and let a few days go by. Students can bring in the two bags to the science fair and show the appearance of the banana with the yeast applied to it compared with the one that was left without yeast. One banana will appear intact while the other eaten away.
Bananas and Oxidation
This experiment shows how bananas turn brown and what can be done to slow the process. Fill several bowls with different liquids such as lime juice, water, salt water and oil. The bowls should be labeled to distinguish the results. Use pH strips that can be bought at a hardware store to determine the pH level of each liquid. Place pieces of banana in the different bowels and set another banana on a plate outside the solutions. You will be able to see the effects of solutions on browning and show that higher pH levels mean a banana will more quickly ripen.