Remember this orange mystery? We finally got the answer!

The orange piece suddenly turned purple mysteriously after just 1 night. And now, everything has a solution.

As reported in early September 2018, a mother in Queensland (Australia) encountered a very rare phenomenon, when the orange piece she cut for her child suddenly turned dark purple after a few hours. Even more strange is that except for the change of color, the taste of orange is also very normal, nothing special.

Nobody knows what happened, even the scientific world. But other sciences are ordinary people in that they will have to thoroughly investigate the causes of mysterious events, so that piece of purple orange is no exception. Experts from the Queensland Science and Forensic Services Laboratory (FFS) collected the mysterious purple citrus fruits, the knife used for cutting, and the sharpened iron knife to test.

Orange pieces change color after a night.

And now, the mystery has already been solved.

According to new results published on ABC, the strange purple color is the product of a very natural chemical reaction, between the compounds in oranges and iron molecules in the knife.

"The analytical results show that the color change of oranges is due to the reaction of anthocyanins - orange pigments - with iron molecules and some other metals when new knives are sharpened " - quoted in the published report. .

"With the knowledge of current science, these color molecules do not have any harm to human health."

Stewart Carswell, FSS chemistry leader, said the team had to extract the purple molecules in the orange. They perform many tests on it, including chemical color indicator testing and spectral analysis.

According to the published results, the inner purple molecule of oranges contains higher levels of iron molecules and some metals than regular orange zones.

Neti Moffitt - the mother in the story shared that her husband sharpened the knife 1-2 nights before cutting the orange. The knife has also been washed before use.

According to Carswell, it is likely that the iron and metal molecules are clinging tightly to the surface of the knife after being ground . When exposed to anthocyanin pigments in oranges, they react and turn purple.

Experts at FSS also tried a normal orange piece that reacts with the iron molecule, and the same purple color also appeared.

The color change of oranges is due to the reaction of anthocyanins - the orange pigment - with iron molecules.

In fact, anthocyanins are present in many dark colored foods: red, blue, and purple. Can be taken for example red cabbage, cherry, grape, berry . However, the concentration of anthocyanin depends on pH and temperature. The lower the temperature, the more anthocyanin tends to concentrate, and this may be the reason why Moffit's orange slice turns purple (she had previously stored the orange in the refrigerator).

With current scientific knowledge, this purple pigment does not cause any health hazards. It's just a case of proving that the foods around us are made up of thousands of chemical compounds, and when exposed to thousands of chemicals in nature will produce interesting phenomena.