A diagram showing how the wax structure reflects light. **rox middleton
Researchers at the University of Bristol can reveal the tiny external structures in the wax coating of blueberries that give them their blue color. This applies to many fruits of the same color, including damsons, sloes, and juniper berries.
In the study, published in Science Advances, researchers show why blueberries are blue, despite the dark red pigment in the skin of the fruit. Instead, their blue color is provided by a layer of wax that surrounds the fruit, which is made up of miniature structures that scatter blue and ultraviolet light. This gives blueberries a blue appearance to humans and blue ultraviolet light to birds. The color blue-UV reflectance results from the interaction of the randomly arranged crystal structure of the epidermal wax with light.
Rox Middleton, a researcher at the University of Bristol's School of Biological Sciences, explains: "The blue color of blueberries cannot come by squeezing'Extraction', because it is not present in the juice of the pigment that can be squeezed from the fruit. That's why we know there must be something strange about this color.
So, we removed the wax and recrystallized it on the card so that we were able to create a whole new blue UV coating. ”
Blueberry. **rox middleton
This ultra-thin colorant is about two microns thick, and although it is less reflective, it is a distinctly blue color that reflects UV rays well, which may have paved the way for new colorant methods.
This shows that nature has evolved to use a very ingenious technique, an ultra-thin layer of an important colorant," Rox adds.
Most plants are coated with a thin layer of wax and have a variety of functions that many scientists still don't understand. They knew it was very effective as a hydrophobic, self-cleaning coating, but only now did they realize the importance of this structure for visible coloration.
Now, the team plans to find an easier way to rebuild and apply the coating. This could lead to a more sustainable, biocompatible, or even edible UV and blue reflective coating.
In addition, these coatings may have the same multiple functions as natural biocoatings that protect plants.
Sedimentation wax. **rox middleton
Rox added: "It's really interesting to discover that there's an unknown coloring mechanism right under our noses, on the popular fruit that we've been growing and eating.
What's even more exciting is the ability to recreate this color by harvesting wax to create a new blue coating that has never been seen before.
It is a dream to build all the functions of this natural wax into an artificially engineered material. ”