Effect Of Suspension Methods And Aging Time On Meat Quality Of Chinese Cattle M.Longissimus Lumborum

Meat quality including five main aspects:eating quality, nutritional value, technical or processing quality, safety and animal welfare. Eating quality of the meat is the most important factor which can determine the value of meat product. Among all the eating quality of the meat, consumers pay more attation on meat tenderness, and meat tenderness (tough ness or resistance to cut) has long been recognized as the most important attribute of meat for consumer acceptability greatly determining consumer satisfaction and thus repeat purchase, However, beef toughness and variation in tenderness are two major problems that the meat industry has to face. Although, the toughness of beef is a huge problem in China which can be solved by long time ageing (14-21d), a lot of energy may be wasted by extended ageing. So, some technology must be taken in to action to solve these problems.The control of key factor during and after slaughting the cattle could influence the palatability of beef product, and the impact is higher than gene regulation. Sarcomere shrinkage during post-rigor influence the tenderness and water holding capacity of meat product. So sarcomere length must be strictly regulated during the process of cooling and aging.Pelvis suspension can stretch the muscle through its own gravity, reducing excessive contraction of the sarcomere and improve beef tenderness. However the research of pelvis suspension in China is limited. Thus, according to the condition of Chinese beef industry, Objectives of the present study were to evaluate the effects of suspension method (including achilles tendon suspension and pelvic suspension) and ageing time(1d post-mortem-21d post-mortem) on quality traits of Chinese cattle (including Qinchuan×Angus Chinese fattened cattle and Luxi×Simmental Chinese unfattened cattle) M. Longissimus lumborum, and and to explore the tender mechanisms from sarcomere length and MFI, in order to improve the beef quality and decrease the energy wasting in China and provide a theoretical basis for the optimization of beef slaughter and processing technology.In this study, the main results are as follows:First, about Chinese fattened cattle, Pelvic suspension (PS) significantly decreased the WBSF of beef muscle at1d and7d postmortem compared with AS. The tenderness with PS at7d postmortem was similar with that of AS at14d. Moreover, PS decreased sarcomere shrinkage during rigor mortis and decreased purge loss of LL significantly, but had no effect on meat color and myofibril fragmentation index. In addition, ageing time had significant effect on pH, meat color, Warner-Bratzler shear force, and myofibril fragmentation index of LL muscle.The result of Chinese unfattened cattle was similar with Chinese fattened cattle. Pelvic suspension significantly decreased the WBSF of LL at1,4and7d postmortem compared with AS. The tenderness with PS at14d postmortem was similar with that of achilles tendon suspension at21d. PS increased sarcomere length and decreased purge loss during aging. Furthermore, the Correlation coefficients between MFI and shear force increased with aging.To conclude, Pelvic suspension method can improve beef quality by controlling sarcomere shrinkage during rigor mortis, which is valuable to be introduced to the beef industry in China for rapid (within7days) improvement of beef tenderness and decreased ageing time of Chinese cattle.