By Jessica Born / March 29, 2018

The eggs-cellent science of dyeing Easter eggs

Dyeing and decorating eggs is a must in many households around the Easter holiday. Generally, families use the ready-made dye tablets you can snag in a box on any endcap in the supermarket. It’s a simple process: pour in water and vinegar, drop in the dye tablet, plop in the egg, stir around, tap off the excess, and dry. 

Pretty straightforward procedure, right?

Well, during that process, there’s actually some pretty cool science that occurs to make the transformation take place. Typical dyes require acidic conditions to make the eggs change color, which is why the everyday staple of vinegar is used.

Let’s break down why.

An eggshell is made from calcium carbonate. Just on the exterior of the shell is a protein cuticle, sometimes called a bloom. This cuticle can’t be seen, but it protects the egg from debris and bacteria.

The eggshell and cuticle react to the acid that has been added to the dye. First, the acid breaks down the shell, providing more surface area for the dye to attach to. After you drop your egg into the dye, the little bubbles you see on the liquid’s surface are carbon dioxide gas bubbles, which is an indication that a reaction is occurring. The acid adds positively charged ions, hydrogen protons, to the mix – this is called protonation. The negatively charged molecules in the protein cuticle and the eggshell are like a magnet for the extra hydrogens that collect on the surface along with the dye. 

(Note: The cuticle is sometimes washed off in commercial preparation for distribution, which is one variable that can determine how vibrant your dyed eggs become.)

Egg-coloring-natural-dye-1366-0318.jpg

If you want to skip the dye this year and try using natural coloring, look no further than beets, cabbage, turmeric, blueberries, and onions. We can thank chemistry for these natural options. But don’t be surprised if some natural ingredients don’t result in the colors you expect. Red cabbage, for example, results in blue eggs (or green if you’re using brown eggs)! For tips and instructions, check out this source or this one. 

Bonus: Want to know how to get perfectly boiled eggs so they’ll survive the hunt (and make great deviled eggs afterwards)? Science, again, is here to save the holiday! Check out this article from Smithsonian Magazine

Sources:
The Chemistry of Easter Egg Dyeing
Eggs to Dye For

 

TOPICS: BEYOND THE CLASSROOM, IDEAS & INSPIRATION, Homeschool, Science, Activities

Jessica Born

Written by Jessica Born

Well, hey there! I’m the digital marketing manager for Pitsco Education. Marketing and special events have been my jam for about the last decade. I’m an alumna of Kansas State University and the University of Arkansas. I fill my Pitsco days with social media management and supporting video and web projects. My weekends are for time in the kitchen, real estate and home projects, and adventuring with my husband and two pups. The best part of my role here is getting to bring creativity and organization to our efforts to connect with YOU!