I recently discovered my sons like eating hard boiled eggs. I had no idea they liked them, until joining some friends for a meal that included hard boiled eggs, and my youngest couldn’t stop eating them! So, I bought some eggs for us the next day, and boiled them. Then I got an idea! Why don’t we add some fun to these eggs and try to use natural dyes to color them? We could further experiment by testing whether each natural egg dye affects how an egg tastes!
We started our experiment with researching possible natural dye sources and seeing if we had any. Our research (and available materials) led us to decide to try 5 natural egg dyes.
The dyes we chose to try were:
- Red Cabbage
- Yellow Onion
For the coffee dye, I used leftover coffee grounds from my morning coffee. I poured 1/2 cup of used grounds into a coffee cup, then poured 1 cup of boiling water over the grounds and set it to the side to brew. After 30 minutes, I strained the grounds out of the coffee cup, and into a heat safe cup. Once the coffee was cool, one of my sons carefully lowered a hardboiled egg into the dye. We also dumped some of the used grounds on the egg (after my husband’s suggestion) to see what affect they had on the egg dye. We then left the egg in the dye for 2.5 hours, then carefully removed it from the dye using prongs.
Strawberry & Blueberry Dyes
To make red and purple dyes, we tried using strawberries and blueberries. We started with 1 cup of boiling water, added 1/2 cup of the berry of choice, then let it boil for 2 minutes. Then we strained the fruit out of the mixture over a heat safe cup, then set the cup off to the side to cool off. Once the dye was cool, we lowered a hardboiled egg into the cup. We returned to the dye 2.5 hours later, and carefully removed the egg from the dye using prongs.
Red Cabbage Dye
Red cabbage is a really fun natural dye. First of all, its called red cabbage, but its actually purple. Not sure why, but I wasn’t there when they named the cabbage. Anyways, I chopped up some of the cabbage into this strips, then added the strips of cabbage to a pot of boiling water. We let it simmer for about 2 minutes, then strained the cabbage out of the dye. We all looked at the cabbage dye and realized it was purple! But we already had a purple dye, from the blueberries. Fortunately, I knew a little chemistry trick we could use.
Red cabbage contains an indicator pigment molecule which will change colors when mixed with other liquids. The color change depends on the pH level of the liquid added to the red cabbage liquid. For more details about pigment indicators, check out this article. I looked around the kitchen and found baking soda. On a pH scale, baking soda is considered a base, and will change red cabbage liquid to blue. We added 1/2 a tsp of baking soda to the liquid cabbage, and voila! The dye was suddenly blue!
After the color change, we set the now blue dye off to the side, and waited for it to cool down. Once cool, we lowered a hardboiled egg into the dye, and left it there for 2.5 hours. When the dying time was over, my middle son carefully removed the egg from the dye, using prongs.
Watch this video to see the cabbage dye change from purple to blue!
Yellow Onion Dye
Yellow onion was perhaps the easiest dye to make. We boiled 1 cup of water, then just peeled off the outer layers of a yellow onion (didn’t need to cut the onion or anything) and added the layers to the boiling water. After 2 minutes, we strained the water, and we had yellow dye! We strained the onion out of the water, and set the yellow dye off to the side to cool. Once cool, we carefully lowered a hardboiled egg into the yellow dye, and left it there for 2.5 hours. We carefully removed the egg out of the dye, and set it to the side to dry.
Observations from our Natural Egg Dye Experiment
Once all the eggs were removed from their dyes, we set them all out to compare our results.
Blueberry Natural Dye: The top right egg is the egg dyed with blueberries. While the color is not very deep, you can still tell that it now has a light blue tint to it.
Onion Natural Dye: The top left egg is the one dyed with onions. The onion dye was by far the starkest color change. Instead of white, the egg is now a dark orange color. Pretty amazing results!
Strawberry Natural Dye: The egg in the middle is the one dyed using strawberries. Similar to the blueberry dye, the color is not very deep, but you can see a slight pink tint to the egg.
Coffee Natural Dye: I found this egg dye pretty interesting, due to the different textures. We hypothesized that the texture was due to the coffee ground we dumped on top of the egg but would need to run a more controlled experiment to confirm our guess.
Red Cabbage Natural Dye: This egg was a light blue as well but was definitely more vibrant than the coloring from blueberries.
Natural Egg Dye Taste Test Results:
After all our eggs were dry, we decided it was time for the taste test. Afterall, who doesn’t want to try a coffee flavored egg? Unfortunately, neither the egg white nor the yolk absorbed any of the natural dye taste. We did a little research about parts of an egg and learned there is a membrane between the eggshell and the egg white that likely prevents any of the dye from permeating (going into) the egg white and yolk.
For more of our experiments, try some of these:
Brown Egg in Vinegar Experiment
Crystal Science Experiment at Home
Fun Water Experiment to Cool off in the Heat!
Beyblade Experiment: What affects Momentum?
Easy Beyblade Science Experiment: Explore Different Types of Beyblades
Easy and Fun Garden Preschool Science Experiment