Edible pH Indicators Color Chart

Edible pH Indicator Color Chart

This chart of edible pH indicators shows the color chages that occur as a function of pH.
This chart of edible pH indicators shows the color chages that occur as a function of pH. Todd Helmenstine

Many fruits and vegetables contain pigments that change color in response to pH, making them natural and edible pH indicators. Most of these pigments are anthocyanins, which commonly range in color from red to purple to blue in plants, depending on their pH.

Plants containing anthocyanins include acai, currant, chokeberry, eggplant, orange, blackberry, raspberry, blueberry, cherry, grapes and colored corn. Any of these plants may be used as pH indicators.

How to See the Colors

To change the colors of these plants, you need to increase their acidity or alkalinity. To see the color range:

  1. Blend or juice the plant to break open the plant cells.
  2. Squeeze out as much solid matter as possible by pushing the puree through a strainer, paper towel, or coffee filter.
  3. If the juice is dark, add water to dilute it. Distilled water won't produce a color change, but if you have hard water, the increased alkalinity could change the color.
  4. To see the acid color, add lemon juice or vinegar to a small amount of the juice. To see the base color, add a small amount of baking soda to the juice.