Optionals

Apple Experiment: Prevent Browning

1. Discuss the reason apples brown after being cut.

-It is a chemical reaction when the enzymes in apples are exposed to oxygen.

2. Have students choose household liquids to put an apple slice in. *Make sure you have lemon juice and get them to choose that as one of their liquids.

3. Have students list their choices.

4. Have students make a hypothesis. "I think that _________ will keep the apple from browning."

5. Leave one apple slice with nothing in the cup (no liquid). Fill all the other cups or bowls with enough liquid to cover the apple slice. Leave them for about 1 hour.

6. Have a discussion or have students write what they notice about what they see.

7. Have them write which one kept the apple from browning and whether thier hypothesis was correct.

8. The lemon juice keeps the apple from turning brown because it is full of absorbic acid (Vitamin C) and has a low PH level. The oxygen works with the absorbic acid before the enzymes in the apple, so it slows the browning for the apple.