Quality Traits And Sensory Evaluation Of Beef In China

This study were collected from the five manufacturers of domestic five level（sA1-A5）of thefour varieties of fattening beef （n=25）. After the beef cattle was slaughtered, the carcass hasa maturity process about72hr at4℃, the meat was graded according to the Japanese beefcarcass grading standards to be assessed. Take12to13rib longissimus muscle （sirloin partsof longissimus muscle） to study the rapidly frozen samples of vacuum packaged, andtransported to the laboratory in a frozen state. This study investigated the performancebetween different varieties of fattening cattle; analysed the different grades of the chemicalcomposition and meat quality differences; Through the above analysis and sensory evaluation,to work out recommendations to the high-grade beef consumption direction. The productionperformance characteristics taken from three different fattening cattle, including live weight,dressing percentage, fattening months; chemical composition analysis of intramuscular fatcontent and moisture content analysis; quality analysis includes the shear force values andcooking loss analysis. Sensory evaluation: using a9-point scale steak tenderness, juiciness,flavor and overall acceptability of preference evaluation. In addition, the fattening of beef ofTBARS （the grade of fat oxidation）, pH, volatile substances were determined, technicallydiscriminant fattening the difference between beef grades to the new index.The results showed that the increasing grades of consumer tenderness, juiciness, flavor andoverall acceptance rate were increased with the quality grade（P<0.05）; tenderness sensoryscores and the corresponding shear force values exist significant negative linear correlation;although there is no difference in pH values between the grades of high-grade beef meat andthe normal beef, the pH values were slightly higher than the pH value of the ordinary beef; ofTBARS also appeared to increase with the quality grade, was significantly decreased.According to the results:1. The experiments confirmed that as the meat grade rise, the difference between theproduction performance among grades significantly, especially fattening-month-oldincreasing as the grade increasing. The experiments confirmed that as the meat grade up, fattening age and live weight increased significantly. However, the slaughtering rate and nosignificant change between the grade.2.With the increasing in the grade of meat, the fat content（IMF%）has a significant increasein the four varieties of fattening beef intramuscular fat content of4.26%to24.55%, while themoisture content and fat content（IMF%） have a significant negative （Y=72.88-0.65X,R~2=0.69, P<0.01）, In addition, quality indicators, cooking loss and purge loss of moistureindex and fat content （IMF%） was significantly negatively correlated. Different breedsincluding the local breed and JB, with the different meat quality grade, is basically to reachthe Japanese domestic breeding（the IMF%）in different grad（edomestic hybrid and cattle A15.1%, the A5from20.9%to34.0%）. In different grade, intramuscular fat content （IMF%）of the local breed can reach the concentration range of JB, with the production of marbledbeef and even snow beef potential.3. The results showed that the fat content （IMF%）significantly affect beef tenderness （P<0.01）, tenderness and fat content （IMF%） wassignificantly positively correlated （Y=9.24-0.0008X, R~2=0.67, P<0.01）. In addition, instrict accordance with the Japanese grading standards, up the A3grade, the shear force valueof4.13±0.84Kg, the sensory score5.59±1.62,11.52±2.48, juiciness score6.16±0.22, theflavor is5.96±0.57, integrated score5.97±0.37. These results are significantly greater than theA1and A2grade. The fat content（IMF%） in A3and above the grade has an average of9.38%, also to ensure the juicy of the meat. Shear force values below in the4.13Kg, all thesensory values are above six, while the flavor substances very rich, and more content. More inline with the requirements of domestic consumers, so the beef in the domestic, A3and abovecan be grouped into the context of high-grade beef.4. When beef shear force values>5.3Kg, consumers considered the beef is tough, do not like;when the shear stress values<4.0Kg, consumers think that the beef was more tender.According to current consumer preferences and sensory perception of the consumer, the A4grade could be used as the target of China’s fattening beef.