"Harvest Some Cabbage and Test Your Candy"

Preparing the cabbage:

1. Break apart a red cabbage leaf and place into a quart-sized Ziploc bag.

2. Place enough water to cover the leaf and seal the bag.

3. Mash the red cabbage to allow the juice from the leaf to mix with the water. Continue until your water is purple in color.

4. Pour off the purple cabbage water into several clear cups.

Preparing the candy:

5. In several cups break up pieces of several different samples of sour candy.

6. Place enough water to cover the candy.

7. Allow the water and candy to mix, this may take several minutes.

Test the candy:

8. Test your sour candy by adding each candy-water mixture to the purple cabbage water and observe the color change.

Explanation: Candy is sour because it contains compounds called acids. These acids come from fruit and include: citric, malic, ascorbic, tartaric, lactic, fumaric. One characteristic property of acid is the sour taste. Acids contain an important element called HYDROGEN which is released when placed in water, giving the acid behavior. In science we measure the amount of hydrogen and record it as the pH (the pH scale ranges from 0-14, acids have pH values 0-7).

The juice from red cabbage can be used to test the pH of sour candy. Red cabbage is considered a natural acid indicator which means it will undergo a color change when in contact with an acid (turns purple to red or pink).