The objective of the research study was to determine the changes in the texture parameters and sensory properties of the skeleton longissimus lumborum (ML) and semitendinosus (ST) muscles obtained from the carcasses of four cattle categories, i.e. dairy calves (n = 20), heavy calves (n = 20), young cattle (n = 71), and cows (n = 10) during a 12-day aging period. In the post-mortem meat samples collected on the 2nd, 7th, and 12th day after slaughter, the shear force, shear energy, and myofibrillar fragmentation index (MFI) were measured as well as an organoleptic evaluation on a 5-point scale was performed. In addition, on the 2nd day after slaughter the basic chemical composition and the content of haem pigments were determined. The muscles of young animals, i.e. heavy calves and dairy calves, contained less fat (on average, 1.25 % less in ML and 0.98 % less in ST) and less haem pigments (97 ppm less in ML and 67 ppm less in ST). Also, those muscles contained more mineral compounds in the form of ash (0.20 % in ML and 0.23 % in ST) and more water (0.94 % in ML and 0.28 % in ST) in comparison to the mature animals, i.e. young slaughter cattle and cows. On the subsequent days of aging, the lowest values of shear force and shear energy, and the highest values of MFI were reported in the muscles of dairy calves (on average, 70.59 N, 0.31 J, 105.84 in ML and 44.27 N, 0.19 J, 113.70 in ST). Different values were reported as regards the muscles of cows, respectively: (109.37 N, 0.46 J, 91.19 in ML and 93.73 N, 0.39 J, 99.61 in ST). During the 12-day cold storage period, a significant improvement was found in the texture and sensory properties of the meat of all four categories of cattle, as was an increase in MFI thereof. The highest decrease in the shear force was reported in the two types of muscles of heavy calves (55.99 % in ML and 40.62 % in ST), and the lowest in those of the cows (39.62 % and 27.04 %, respectively). In the case of changes in MFI, the highest relative increase was found in the ML muscle of the cows (60.99 %) and in ST of the young slaughter cattle (50.46 %), whereas the lowest in the two muscles of the dairy calves (38.85 % and 27.11 %, respectively). The highest ratings were given to the sensory properties: tenderness, juiciness, and palatability of the meat samples from the dairy calves on the 12th day after slaughter (on average, 4.68 – 4.83 pts.) followed by heavy calves (4.25 – 4.51 pts.) and young slaughter cattle (4.18 – 4.40 pts.). Those properties of the muscle samples from cows were rated the lowest (3.90 – 3.98 pts.).
beef, aging, chemical composition, shear force, myofibrillar fragmentation index