Diffuse reflectance spectroscopy to quantify the met-myoglobin proportion and meat oxygenation inside of pork and beef

The potential of diffuse reflectance spectroscopy (DRS) to quantify the met-myoglobin (met-Mb) proportion and meat oxygenation inside of pork and beef was examined. First, reflection spectra were obtained from pork (n = 52) and beef (n = 43) samples under fresh and stored conditions. Second, the DRS algorithm was applied to the reflectance spectra to calculate the met-Mb proportion and oxygenation of the meat. Lastly, a regression model was developed showing the change in the met-Mb proportion and oxygenation during met-Mb formation and degradation. A linear relationship existed between the DRS-based computed data and the known met-Mb proportion with a high correlation (R2 = 0.9999) and a low error (0.86%). Measurement of the meat samples revealed a linear increment of the met-Mb proportion (R2 = 0.77) and a quadratic change in the oxygenation (R2 = 0.44) during the met-Mb formation process. This study demonstrated the ability of DRS to quantitatively analyze the relative content of myoglobin derivatives in both pork and beef.