Blueberries, those small fruits that give our plates and salads their blue color, hide an interesting scientific mystery behind their appearance. Researchers at the University of Bristol have discovered the secret behind its vibrant colour, revealing that the color is not simply a matter of pigmentation, but the result of a complex physical interaction.
Contrary to what one might think, the distinctive blue color of blueberries is not due to a pigment present in the fruit’s skin, but rather a layer of wax that surrounds them. This layer is made up of tiny structures that scatter blue and ultraviolet light, giving it its distinctive color. This phenomenon, known as blue-UV colored reflectance, arises from the interaction of epicuticular crystalline structures of the wax with light.
Scientific method and conclusions
The research team, led by Rox Middleton, Research Fellow at Bristol’s School of Biological Sciences, used an innovative method to study this phenomenon. By removing the wax and recrystallization of it, they were able to replicate the UV-blue coloring effect, which showed that the blue color of blueberries could not be achieved by simply squeezing the fruit.
This discovery not only sheds light on the mysteries of natural colours, but also opens the door to new possibilities in the manufacture of colours. The developed technology could lead to the production of more sustainable, bio-compatible and even edible UV and blue paints, with applications beyond aesthetics, including hydrophobic and self-cleaning functions.
The study from the University of Bristol reminds us of the innovative solutions that nature provides and how, through science, we can learn to replicate these miracles. Future efforts will focus on discovering simple ways to recreate and apply this coating, which will promise advances in artificially engineered materials that mimic the functionality of natural wax.