An indicator is a compound that changes color when you dip it in different things, like vinegar, alcohol, milk, or baking soda mixed with water. There are several extracts you can use from different substances. You’ll find that not all indicators are affected by both acids and bases. Some only change color for just an acid, or just a base. Turmeric, for example, is only good for bases. (You can prepare a turmeric indicator by mixing 1 tsp turmeric with 1 cup rubbing alcohol.)

Easy Indicator Juice
Cut the substance you want to turn into your”indicator” into small bits. Boil the chopped substance for five minutes. Strain out the pieces and reserve the juice. Cap the juice (indicator) in a water bottle and you’re ready to go. What different substances can you use? We’ve had the best luck with red cabbage, blueberries, grapes, beets, cherries, and turmeric. You can make indicator paper strips using paper towels or coffee filters. Just soak the paper in the indicator, remove and let dry. When you’re ready to use one, dip it in part way to you can see the color change and compare it to the color it started out with.

Turn this into a science fair project! Make sure you only change ONE thing when you transform this into a science fair experiment…. you can change the type of substance you use, or the stuff you test with the indicator.  For example, you could try beets,  blueberries, grapes, cabbage, cherries, and turmeric and test lemon juice with the different pH strips.  OR you could make a cabbage-based indicator and test lemon, limes, oranges, etc.  Have fun!