Effect of marbling and chilled ageing on meat-quality traits, volatile compounds and sensory characteristics of beef longissimus dorsi muscle

Effects of marbling and chilled ageing on technological quality traits, volatile compounds and sensory characteristics of Hanwoo beef were investigated. Three marbling groups of longissimus dorsi muscles (n ≤ 10 each), namely, high marbling (HM), moderate marbling (MM) and slight marbling (SM), classified according to the Korean carcass-grading system, were used. Each longissimus dorsi muscle from each marbling group was divided into two equal portions, vaccum-packaged and then assigned to 1- and 7-day ageing groups. The ageing was conducted in a chilling room at 4°C. Marbling level was significantly correlated with intramuscular fat content, shear force, cooking loss, tenderness and flavour. Particularly, the HM group had a lower shear force value, and higher fat content, lightness, tenderness, flavour and overall-liking scores than did MM and SM groups. Ageing significantly reduced the shear force value and increased tenderness, flavour and overall-liking scores for the HM group. Twenty-four volatile compounds were significantly influenced by marbling and/or ageing. The SM group had the highest concentration of benzaldehyde, while HM group had the highest concentrations of octanal, nonanal and dimethyl sulfide. In conclusion, our results demonstrated that a high marbling positively affected some technological quality traits and eating quality of beef, and ageing for 7 days reduced the shear force and improved eating quality of samples in the HM group, suggesting that the highly marbled beef responds to the ageing at a faster rate.