We had so much fun learning cooking and science this week in our first ever, Kitchen Science camp. We used purple cabbage to make some color changing noodles. Purple cabbage contains anthocyanin which is an indicator, meaning it can indicate whether a liquid it comes in contact with is an acid, neutral, or base. In our recipe, we soaked rice noodles in purple cabbage saturated water which was a deep indigo color. The rice noodles soaked up the water and took on the indigo hue themselves. Then came the fun part, each student was handed a lemon. As they squeezed lemon juice onto their noodles, the anthocyanin reacted with the acid in the lemon juice and turned the noodles pink! Once they were done playing with the color changing, they added butter or soy sauce and enjoyed eating their indigo and pink noodles.

Color Changing Noodles
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  • 1 package of rice noodles
  • ½ a head of purple cabbage
  • 1 lemon, cut into wedges
  • Optional: butter or soy sauce for serving


  1. Place the cabbage in a large pot and cover with water. Boil the cabbage until the water is deeply saturated with color, about 10 minutes. Remove pot from heat.
  2. Remove the cabbage and place the rice noodles in the purple water. Let them soak for 7-8 minutes until just softened, then remove half, and let the remaining half soak for an additional 3-5 minutes. You can also soak a few of the noodles in lemon juice to have some pink ones to swirl in. Just be sure to rinse them before serving for the best taste. Skip step 4 if soaking the noodles in lemon here.
  3. Drain the cabbage water and swirl together the blue and purple noodles.
  4. Squeeze a bit of lemon onto the noodles and watch as the noodles slowly change to pink!
  5. Add butter or soy sauce to taste before eating.


The Science: Cabbage juice acts as an indicator, meaning it changes color as the pH changes. A magical water-soluble pigment in red cabbage called anthocyanin changes color when it is mixed with an acid or a base. It’s purple when it’s in contact with neutral pH liquids (think water), pink when it touches acids (think lemon juice) and green when it touches bases (think baking soda).

Definitions: Indicator- a substance that indicates the presence or concentration of an acid, base, or neutral ingredient.