Instrumental evaluation of meat quality characteristics of Belgian slaughter pigs

The objective measurements of acidity (pH), light scattering (FOP), conductivity (PQM) light absorption (Gofo), lightness (Labscan L*), redness (Labscan a*), yellowness (Labscan b*) and water holding capacity (WHC) were evaluated for their suitability in estimating meat quality in a population of about a thousand slaughter pigs. The animals were divided in three meat quality categories based on pH(1): 21.2 % of the carcasses belonged to the PSE class, 10.4 % to the slightly PSE class and 68.4 % were considered as normal meat. As expected, all the measured meat quality parameters, except Labscan a*, showed significantly different results between the PSE and the normal meat class. Even between the normal meat and the slightly PSE meat most of the parameters were significantly different. The parameters measured in the slaughterline (45 min. post mortem) were significantly correlated with each other: pH(1)-FOP1 (-0.72), pH(1)-PQM(1) (-0.69), FOP1-PQM(1) (0.80). The predictability of the ultimate meat quality (paleness, hue, exudative) with the initial measurements in the slaughterline was rather low. Principal component analysis showed that 56 % of the total variation in the different meat quality parameters could be explained by the first three principal components. Based on the first principal component a distinction could be made between PSE and normal meat, but the intermediate slightly PSE meat class strongly overlapped with both meat categories. The best parameters for the prediction of PSE meat, based on pH(1), were FOP1 and PQM(1).