Comparison of Marbling Fleck Characteristics and Objective TendernessParameters with Different Marbling Coarseness within Longissimusthoracis Muscle of High-marbled Hanwoo Steer

摘要

It is important to understand how marbling traits and tenderness differ among beef steaks from the carcass grading site and other regions within the longissimus thoracis (LT) muscle, as these characteristics are closely associated with consumer acceptability and willingness to purchase. Thus, the aim of this study was to compare the marbling fleck traits and objective tenderness parameters in the groups classified by the coarseness index (CI) of marbling fleck (high and low groups) at the carcass grading site (13^th thoracic vertebra; 13T) and three different locations (13T, 9T, and 6T) within the LT muscle from well-marbled (marbling score 7 to 9) Hanwoo steer. Image analysis showed that the longitudinal locations had a significant effect on marbling fleck traits. The total area of large marbling fleck divided by the total marbling area (coarseness) was higher at the central region (13T to 12T) compared to the front thoracic region (6T to 5T) in the high CI group (0.23 vs. 0.17, p<0.05), whereas no significant differences were observed in the total number of marbling fleck within the LT muscle in the high or low CI groups (p>0.05). Location effect on objective tenderness parameters within the LT muscle was somewhat limited,although the high CI group had a lower Warner-Bratzler shear force (WBS) valuethan did the low group (p<0.05). Taken together, thedegree of coarseness of marbling fleck decreased from the carcass grading siteto the front thoracic site, whereas the objective tenderness parameters,including WBS and hardness, of the grading site did not differ from the otherregions within the LT muscle.