As Willy Wonka says…come and taste the…holographic rainbow?
This is Sandra Tsing Loh with the Loh Down on Science.
Shining, shimmering, splendid – holograms! Their rainbow colors show up on credit cards, stickers, even currencies. Holograms are so fun and colorful – if only we could use them on food! But inks used to produce holograms can be toxic. How can we create safe, delicious holographic snacks?
Enter Bader AlQattan from the University of Birmingham and colleagues.
The researchers made a mixture of corn syrup, water and vanilla extract. This sweet liquid was spread about a hair thick and allowed to harden. A thin layer of non-toxic black dye was painted on top. Then, using a laser, the researchers made a pattern of tiny chips in the dye at NANO scale!
When the researchers tilted their creation at different angles under a microscope – Ta-dah! Light bouncing off the nano-chips produces that holographic rainbow!
Once a suitable food-safe dye is created, the sky’s the limit! Feast your eyes on sweets displayed in all the colors of the holographic rainbow!
It’s a world of pure imagination! Oompa Loompas not included.
Reference:
AlQattan, B., Doocey, J., Ali, M., Ahmed, I., Salih, A. E., Alam, F., Bajgrowicz-Cieslak, M., Yetisen, A. K., Elsherif, M., & Butt, H. Direct Printing of Nanostructured Holograms on Consumable Substrates. ACS Nano, 15(2), 2340–2349. (2021). https://doi.org/10.1021/acsnano.0c02438