What's New

Color of Fresh Meat in Supermarket Display Cases

The color of fresh meat in supermarket display cases forms a first impression that strongly influences consumers' selection of fresh meat. The pigment myoglobin which determines the color of fresh meat undergoes various chemical reactions to form other pigments. These reactions are triggered by light, heat, and oxygen availability.

For meat science references and excerpts click here.

Temperature and Fresh Meat Color in Supermarket Meat Cabinets

Temperatures above -1.5° C (29.3° F) encourage the exponential growth of bacteria, which consume the oxygen near the surface of the meat, hastening the creation of the brown pigment metmyoglobin.

Even small temperature increases have a profound effect on the growth of bacteria which leads to meat spoilage. Regular display case lighting emits heat, as well as radiation that is transformed into heat when it is trapped within the meat’s packaging, and can cause the surface temperature of displayed meat to be much higher than the temperature of the refrigerated display case.

[Top]

pH and Fresh Meat Color in Grocery Store Meat Cabinets

The pH of fresh meat naturally falls from about 7 to about 5.5 over a period of 24 hours after the animal is slaughtered. However, genetic problems or mishandling of the animal or carcass can affect the pH of the muscle tissue adversely.

If the pH drops too rapidly or is at a very low level, the meat becomes pale, soft, and exudative (PSE), and if the pH does not drop at all or is at a high level, the meat becomes dark, firm, and dry (DFD). Dryness hinders the muscle tissue’s ability to absorb oxygen and bloom. These terms are often used to describe problems with pork.

[Top]

Promolux True Color Definition Lamps

Promolux balanced spectrum lamps emit lower levels of heat, ultraviolet radiation and damaging visible spectrum radiation than regular supermarket fluorescent lamps, thus prolonging the blooming period of meat and reducing the rate of meat discoloration. Compared to other fluorescent lighting, Promolux lamps emit 86% lower UV B radiation, a shorter wavelength that penetrates and causes heating, and 52% lower UV A radiation, a longer wavelength that tends to affect surfaces.

In a study conducted by the University of Zaragoza, meat that was displayed under Promolux low UV lamps stayed nearly as fresh as meat that was kept in the dark, while meat that was displayed under regular fluorescent lighting quickly turned brown and began to decompose.

Promolux meat display case lamps are also balanced for true color definition. The yellow and green wavelengths that are predominant in regular fluorescent lighting are the most damaging wavelengths in the visible spectrum.

Promolux lamps emit a more balanced range of wavelengths, including more of the red and blue wavelengths and more moderate levels of the yellow and green wavelengths, thus revealing the bright red color of blooming beef muscle without compromising the white of the fat and marbling.

Lighting sources have a profound effect on the perceived color of fresh meat.

Fresh Meat Displays

Regular supermarket meat display case lighting shortens the brief period when meat is blooming, turning it brown prematurely; increases the rate of bacterial growth; and distorts the meat’s natural color.