We used Fresca as a base for dying our Easter Eggs instead of water & vinegar. We believe the Fresca must be somewhat acidic as it very much allowed the color to stay on the eggs, without vinegar.
The thin layer of yellow you see in the above picture is Olive Oil. We dropped the egg into the Fresca-Labcolor mixture, making it first pass through the Olive Oil so that portions of the egg were coated in oil. The coated portions of the eggs did not take on any color, leaving a marbled or speckled effect.
The Fresca carbonation (with or without olive oil) made a really interesting effect as they bubbled up. They ended up making a fizzy bubbling pattern up the sides of the eggs. The eggs more near the end of the process had less of the fizzy bubbling pattern than the eggs from the freshly poured Fresca.
Other than the drawback of oily eggs, the experiment was a huge success! We loved the different and unique patterns each egg took on. We will definitely have this in our Easter Egg dying repertoire next year! Plus, as an added enticement for more Fresca Eggs, my daily of intake of protein (egg whites) is way cuter now that the eggs are brightly colored nuggets of fun.