What's wrong with the green meat

Meat is an indispensable food in our lives. It can provide us with the protein and fat we need daily and replenish our energy. As every household now has a refrigerator, many people will buy some meat and store it in the refrigerator for later consumption. However, if the meat is not put into the refrigerator, its quality will change, its color will become duller, and it will also emit some strange smell. So what happens when meat turns green in real life? Is it still edible?

The "green glow" in the meat is most likely the result of the "reflective grating effect". When cutting meat, muscle fibers are cut, and many regularly arranged concave and convex structures are formed on the cross section. When light hits this cross-section from the right angle, this optical effect occurs and you can see rainbow-like colors, including various shades from green, yellow to red. The colorful reflections of bird feathers, insect wings and computer discs all work on this principle.

Beef turns green:

There are several possibilities for why beef turns green. One is that it is related to copper ions. If the copper ion exceeds the standard, it may be harmful to the human body. The second possibility is that the beef has been stored for too long or in an unreasonable manner, causing a large number of bacteria to form on the surface and then an oxidation reaction to occur.

You may also have bought water-injected meat. The greening of beef is mainly caused by water injection. After the beef is injected with water, the shelf life will be shortened. After being stored for a period of time, oxidation reaction will occur. The color change may be that the beef has deteriorated. Such beef cannot be eaten.

The blue, green, pink or even gold coloration of the cross-section of beef has nothing to do with the quality of the beef itself or food safety. It is actually because beef is made up of countless muscle fibers, the diameter of which is less than one-tenth the thickness of a hair, so they are almost indistinguishable to the naked eye. But when a piece of beef is cut perpendicular to the muscle fibers, the uneven muscle fibers on the cut surface form a structure called a grating in optics. The grating causes interference of the reflected light, which results in the rainbow-like colors we see.

Whether beef will produce these iridescences depends on the knife skills, light angle, and the water content of the meat. Generally speaking, braised beef is more likely to produce this phenomenon.

This effect is not unique to beef, but can also be found in pork, mutton, donkey meat, dog meat, chicken, duck meat, and fish. However, this phenomenon usually only occurs with cooked meat.

If you slightly change the angle of observation, if it is grating diffraction, the color will change or even disappear. If the color does not change, it is most likely caused by deterioration.

Pork turns green:

Fresh meat has a shiny surface and uniform color. Fresh pork is red or light red, and the fat is white; beef and mutton are bright red, and the fat is mostly yellow; poultry skin is light yellow or white, and the meat is white with a hint of red. As the storage time increases, the meat color will gradually turn reddish brown due to the oxidation of myoglobin. The darker the color, the less edible it is. When the surface of the meat turns gray or gray-green, or even has white or black spots, it means that the microorganisms have produced a large amount of metabolic products, and such meat cannot be eaten.