Effects of three lighting intensities during display on discolouration of beef semitendinosus muscle

Abstract

This study focuses on the changes in colour parameters of beef (semitendinosus muscle) upon the light exposure. In one of the experiments (Experiment I), colour parameters were studied during 60 min of blooming. In the Experiment II, the changes of colour over 168 h of exposure were evaluated. For this purpose, the white fluorescent light of three different intensities, 500, 1,000 and 1,500 lx, was chosen. It is shown that it takes up to 16-18 min for the colour parameters to stabilize after the steak cutting, which is a consequence of increasing availability of oxygen. Beef colour is affected by the light intensity. It was observed that at the beginning of the light exposure, favourable changes took place. However, after few days of exposure to the light, meat colour deteriorates significantly. Changes are mainly related to the redness (a*). The value of a* decreased about 4-7 units (p < 0.05) after 7 days of meat exposure. This significant change of redness is also clearly evident in the visual assessment. White fluorescent light (colour temperature of 3,000 K) with intensity of 500 lx has lower impact on the beef colour than the light with intensity of 1,000 or 1,500 lx. Intensity of 500 lx is more favourable to preserve the desired beef colour, and it could be recommended to use in the retail display. However, further studies taking into account the visual evaluation of beef colour would be useful to confirm this fact. © 2014 The Author(s).