The beef is green, is it because of excessive heavy metals?

This statement is rather one-sided.

In some cases, the green color of beef is often due to an optical phenomenon called "grating effect" rather than a food safety issue. The "grating effect" is a diffraction phenomenon of light. When beef is cut vertically, the muscle fibers are cut, forming many regularly arranged concave and convex structures on the cross section. When these structures are exposed to light, due to the diffraction phenomenon of light, the surface of the beef may appear green. This green light usually has a metallic luster, and the color will change or even disappear when viewed from a different angle.

In addition, this grating effect not only occurs on beef, but also on other meats such as pork and lamb. If the beef turns green and has abnormal phenomena such as a corrupt smell and mucus, it is likely that the beef has gone bad. In this case, the protein in the beef is degraded by bacteria, releasing ions such as iron, sulfur, and copper, causing the beef to change color. Not only does spoiled beef have a greatly reduced taste and nutritional value, it may also be harmful to human health, so it is not recommended to eat it.

Although heavy metal pollution can also cause food discoloration, it is not the only reason why beef turns green. Moreover, heavy metal pollution usually requires professional testing methods to determine. Therefore, it cannot be concluded that the greening of beef is caused by excessive heavy metals.

In short, when buying and eating beef, if you find that the beef is green, you can use the following methods to simply identify it: 1. Observe the color change: If the green light is caused by grating diffraction, the color will change or even disappear when you observe it from a different angle. 2. Check the meat quality and smell: If the beef is green and accompanied by abnormal phenomena such as a corrupt smell and mucus, it is likely to be spoiled. You should stop eating it immediately and dispose of it properly.

Author | Master of Doubao Food Processing and Safety

Review | Ruan Guangfeng, Deputy Director of Kexin Food and Health Information Exchange Center