Differences in Muscle Fiber Characteristics and Meat Quality by Muscle Type and Age of Korean Native Black Goat

To investigate the relationship between muscle fiber characteristics and meat quality traits by age of Korean native black goat (KNBG), four muscles (longissimus dorsi, LD; psoas major, PM; semimembranosus, SM; gluteus medius, GM) were obtained from five adult goat (AG; 18 months old) and five young goat (YG; 9 months old). PM muscle had the highest fiber number percentage (FNP) and fiber area percentage (FAP) of type I, followed by SM, GM, and LD muscles. FNP and FAP of type IIB were significantly (p<0.001) higher in AG than those in YG. YG had higher L* values but lower b* values than AG. The highest L* and b* values were observed in LD muscle (p<0.001). Age and muscle type had detrimental (p<0.001) effect on shear force and collagen content for all muscle in AG as compared to YG. YG had significantly (p<0.001) higher myofibrillar fragmentation index (MFI) than AG for all four muscles. These results suggest that muscle fiber compositions of different muscle types of KNBG depend on age, resulting in variations of meat color, MFI, collagen content, and shear force.

Effect of Slaughter Age on Muscle Fiber Composition, Intramuscular Connective Tissue, and Tenderness of Goat Meat during Post-Mortem Time

This study evaluated the effects of slaughter age and post-mortem time on meat quality traits, tenderness, histochemical analyses, and perimysium thickness in the longissimus thoracis (LT) muscle of the Korean native black goat (KNBG) maintained at 4 °C for up to 21 days post mortem. Samples of LT muscle were obtained from the carcasses of 24 KNBGs, including old and young goats (AG, n = 12, 18 months of age; YG, n = 12, 9 months of age), to measure all analyses during 21 days of post-mortem time. AGs had a higher percentage of type I fiber but a lower percentage of type IIA fiber than YGs (p < 0.05). AGs had higher a* value, lower released water (RW) %, and higher Warner-Bratzler shear force (WBSF) value than YGs (p < 0.05). The perimysium thickness (PMT) of AGs was also higher than that of YGs (p < 0.05). Although the PMT did not change during post-mortem period, the WBSF value of AGs was higher than that of YGs after 21 days post mortem (p < 0.05). The results imply that AGs are tougher than YGs due to their muscle fiber characteristics and thicker perimysium.

Current and future issues facing red meat quality in a competitive market and how to manage continuous improvement

This paper discusses current and future issues facing lamb and beef meat quality and proposes strategies to manage quality improvements into the future. Based on survey data of Australian consumers and whole supply chain profit drivers, it is argued that the three most important quality areas for future research are lean meat yield, eating quality and human nutritive value. These areas have complex biological interactions, both antagonistic and complimentary, which require careful management so as to produce the best outcome for industry and the consumer. It is argued that the best way forward is to undertake collaborative research that encompasses industry production, meat science and genetics simultaneously. The case study of the Australian lamb industry is used as a suggested model for future progression, whereby a large breeding program forms the central focus of numerous research and delivery activities. Another issue raised is the need for strong and cost-effective industry systems that are able to effectively utilise outcomes from genetics, lean meat yield and eating quality to deliver the research results.

The influence of genetics, animal age and nutrition on lamb production - an integrated research program

This paper provides an introduction to this Special Issue of the Australian Journal of Experimental Agriculture. The special issue is dedicated to an integrated research program that was intended to increase the understanding of the effects of breed and genetic selection for live animal traits (growth, muscle and fatness) on carcass and meat attributes. Combined with this are the effects of animal age and nutritional restriction at critical weaning points. The reasons for, and general approach, of the research are outlined.