Trying to Eat Hot Gomtang but 'Surprised'... Is It Safe to Eat Greenish Meat?

Green Fluorescent and Rainbow-Colored Meat Due to Light Dispersion
Do Not Eat If There Is a Spoiled Smell or Sticky Texture

"The meat in the gukbap has a green fluorescent glow. Is it safe to eat?"

The Food Safety Information Service announced that it will produce and distribute a card news containing information about meat that has a green fluorescent glow or a rainbow color. Getty Images, Food Safety Information Service.

On the 27th, the Food Safety Information Service announced that it will produce and distribute a card news containing information about meat that shows a green fluorescent or rainbow-colored glow, which is a common inquiry received annually at the Illegal and Substandard Food Reporting Center.

The green fluorescent glow seen on the cross-section of thinly sliced meats such as jokbal, pork gukbap, and galbitang is a representative case where consumers may mistake it for substandard food, leading to continuous reports and inquiries every year. Examples received by the reporting center include: ▲ fluorescent blue light appearing on beef in gomtang, suggesting severe spoilage ▲ light greenish meat found in pork gukbap ▲ fluorescent substances on bossam meat appearing suspicious, among others.

A case of blue fluorescent meat introduced by the Food Safety Information Service. Provided by the Food Safety Information Service

In response, the Food Safety Information Service explained, "The fluorescent glow on the meat is a phenomenon where muscle fibers on the meat’s cross-section are exposed to light, causing our eyes to perceive a green fluorescent (or rainbow-colored) glow." They added, "Although the green fluorescent glow is often mistaken for spoiled food or contamination by harmful substances, it is a natural phenomenon and safe to consume." However, if the meat emits a foul odor or taste, or has a sticky texture, caution should be exercised and it should not be consumed.

Meat muscle consists of multiple bundles of muscle fibers surrounded by connective tissue. When meat is sliced, the fibers protrude on the muscle tissue surface, creating an arrangement similar to a diffraction grating on the cross-section. A diffraction grating is a surface with many parallel lines engraved at narrow intervals on flat glass or concave metal plates, which, when illuminated, uses diffraction and interference to produce a light spectrum. When light shines on meat in this state, the light disperses on the surface, causing our eyes to see a green fluorescent or rainbow-colored glow.

Lee Jae-yong, Director of the Food Safety Information Service, stated, "By utilizing reports and consultation information on substandard foods, we will identify cases that may confuse consumers and produce easy-to-understand content to contribute to the dissemination of accurate food information." He also urged the public to actively report any witnessed illegal food safety violations or suspected substandard food products to the Illegal and Substandard Food Integrated Reporting Center.