Bloom Time Effect Depends on Muscle Type and May Determine the Results of pH and Color Instrumental Evaluation.

The aim of this study was to determine the effect of 30 min bloom time and the type of muscle on pH and color parameters together with the possibility of estimating these measurements. The research material consisted of 270 samples from 6 muscle types: LD-Longissimus dorsi, LL-Longissimus lumborum, IL-Iliacus, SEM-Semimembranosus, CT-Cutaneous trunci, LTD-Latissimus dorsi. Measurements included pH and color of fresh pork at 0 min, and after 30 min bloom time. Bloom time influenced all analyzed parameters, although to a varying effect, depending on the muscle type. The lowest pH values were noted for dorsal-located muscles (LD, LL), then in the ham area (IL, SEM), and the highest values of the location on the side surface of the carcass (CT, LTD). The large increase in the proportion of L* and a* was observed for CT muscle (20-30%, the highest of all observed) and LTD (20-25%); for LD and LL the largest growth changes were observed for parameters b* (15-20%) and H* (20-30%). The lowest number of strong correlations was noted for LD and CT muscles, and the largest for SEM. A very good fit (R2 > 0.90) of regression equations was achieved in 7 cases. The presented results are an important contribution to the rapid and precise instrumental evaluation of pH and color.