Analysis Of Beef Performance And Quality Of Yellow Cattle And Crossbreed And The Research And Establishing Of Beef Grading System In China

Beef is becoming a favorate food of Chinese people for its good nutrition and palatability. In recent years, the ratio of beef to total meat consumption has increased greatly and people had never given such emphasis on its quality before. The production of high quality beef is coming to birth into a new industry in China, so it is very necessary to find the key factors which greatly influence the industry and define the correct direction of its development. Yellow Cattle are the main cattle in our country with a large amount and wide distribution. Since Yellow Cattle had been used for animal power for a long history, there are seldom researches about their beef performance and the influencing factors. This article aimed to investigate from the aspects of cattle breeding, feeding, beef conditioning and the establishing of beef grading system based on the references to other countries?conditions and the experiments of our Yellow Cattle. The results can be used as the foundation for the resolution of problems existing in the production and make our beef industry develop in a scientific and reasonable direction. The research results indicate: after defining the beef performance characteristics the breed and the nutrition both had the significant effects on beef quality and quantity. Jinnan breed was proved the best breed of beef quality compare with other breeds and the crossbreeds have no better even worse beef performance than Yellow Cattle, which suggested that the direction of breeding and the demand for feeding condition of each breed must be defined. At the same time the dietary with high energy can improve the beef quality greatly. In order to get the products we want, the cattle should be fed with scientific dietary according to the cattle's demands. Conditioning can efficiently improve the beef tenderness and pH. During ageing the activity of calcium active factor (CAF) decreased with the time which indicted that enzyme has certain effects on the tenderization of beef. Myofibril fragmentation index (MFI) is the direct micro characteristic which reflects the changes of beef tenderness. It also decreased with time during aging. At the same time thd MFI wass affected by age also, but this effect will disappear with the development of aging. There were few changes of amount and property of collagen during aging which reflects that the collagen had little effects on beef tenderization. Age, however, had strong correlation with collagen and this relationship is not affected by conditioning. Age therefore was proved an important factor which related to beef tenderness. The lack of the method and standard of beef grading system was the key limited factor for the development of beef industry in our country. A reasonable beef grading system can constraint and guide the beef production and consumption and give an end to the condition without standard. The results of quality research indicate: tenderness, juiciness and flavor which are three aspects of beef quality inter-impacted and influenced each other with the same changing direction. Therefore , tenderness can be selected to be the representitive characteristic for research. The factors which greatly influene tenderness and can be measured conveniently were the main influencing factors of juiciness and flavor also. The tenderness was proved not to be predicted by a linear equation using the tested indexes. The maturity and marbling were finally selected to be the characteristics fo...