Obtain four uncut red apples. Place one apple in a refrigerator, one in a brown paper bag, one in a basket and one left undisturbed on the counter. Observe the changes in the apples over the course of two weeks. The apples left out in the open should deteriorate faster than those kept in the refrigerator and bag.
Slice two apples using an hand-held apple slicer. Place three slices each in four separate bowls of water, lemon juice, orange juice and milk. Leave out three slices on a paper towel so they are only exposed to the air. Observe the changes that take place over a period of a few hours. The apples exposed to the air should brown first while the apples in the acidic liquids will turn brown at a slower rate.
Wash and cut a red apple into slices using a hand-held apple slicer. Close your eyes and take a bite of the apple slice. Write down how it taste using descriptive adjectives. Close your eyes again and hold an onion slice to your nose while taking a bite of the apple. Record how the apple tastes now. The smell of the onion should overpower your taste buds, causing the apple to taste like an onion. Remember to taste only what you are directed to taste and beware of any allergies.
Obtain several apples of varying colors. Slice each apple open using a hand-held apple slicer. Place the apple slices face up on a paper plate and label each apple according to color. Place one strip of pH paper on the top of the slice. Wait a few moments for the juice to be absorbed in paper. The sweeter apples will have an acidic reading while less than sweet apples will appear more basic.