Grade: The second prize
Winners: Zhou Guanghong, Zhu Yiliang, Xu Xinglian, Peng Zengqi, Li Chunbao, Xu Baocai, Zhang Nan, Zhang Jianhao, Gao Feng, and Huang Ming.
Collaborators：Nanjing Agricultural University, Jiangsu Yurun Meat Industry Group Co., Ltd., Jiangsu Food Group Co., Ltd
Meat industry is the biggest food industry in China with its production value accounting for 12% of the total value in food industry. About 70% of the meat products are consumed in the form of fresh meat in China, including fresh meat, chilled meat and frozen meat. Chilled meat refers to the kind of fresh meat that sufficiently cool down after slaughter and is kept at -1~7℃ for later processing, storing, transporting and selling. This meat product has the advantages of effectively inhibiting the growth of microorganisms in it, reducing loss of its nutrition, and guaranteeing and improving its general quality. Therefore, chilled meat has completely replaces fresh meat on the market in developed countries. China started production of chilled meat in the 1990s when this meat product made up of less than 1% of that of fresh meat. At that time, the production techniques and processes were backward and low, and the key equipment had to be imported. As a result, meat quality was not effectively controlled, its weight loss was serious during carcass chilling, and its shelf life was short. These disadvantages resulted in large amounts of spoiled and weight-loss meat causing an economic loss of as much as 35 billion RMB per year. Against this background and situation, this program was started aiming at developing and applying the key technologies of meat quality control and the related equipment.
(1) Clarifying the underlying biochemical mechanisms on changes of meat quality attributes in chilled meat and identifying the critical control points of the meat quality.
Chilled meat for The mechanism for water holding capacity, discoloration and tenderization were studied, and it’s found that, a fast pH decline and activation of phospholipaseA2 at early postmortem time induce the disruptionof cell membrane and the weakening of cell function, which further results in juice loss in fresh meat; that metmyoglobin reductase was the key factor in stabilizing chilled meat color, and the enzymes involving energy metabolismandµ-calpain and caspase 3 regulated the rate of beef tenderization; and that meat tenderness had a good relationship with intramuscular fat content, meat color, and maturity. The principles of PACCP and HACCP were applied to identify critical control points of chilled meat quality.
(2) Developing the key processing technology for chilled meat quality control, and effectively solving the problems of high rate of spoilage, high drip loss and short shelf life of chilled meat.
An intermittent spraying was developed and applied by effectively reducing the weight loss of carcass from 2.5% to 0.9%. A decontamination technology that is lactic acid spraying was developed and it was applied in combination with hurdle technology by reduce the total count of bacteria on the surface of carcass from 1*105cfu/cm2 to 1*104cfu/cm2. Several packaging technologies, including vacuum shrinkage packaging, atmosphere modified packaging and cold chain were applied to extend the shelf life of chilled pork and beef to 24 and 45 days, respectively. An integrated technique was applied to reduce the incidence of PSE pork from 20% to 10%. Low-voltage electrical stimulation was applied to accelerate meat tenderization. Finally, the first meat quality grading system was developed in China.
(3) Developing the key equipment for chilled meat processing and promoting domestic manufacturing of the equipment.
Highly efficient spraying facilities for meat chilling was developed by automatically adjusting water pressure, flow rate and angle of spraying during meat chilling. Several slaughtering equipment was developed. In addition, intermittent and continuous air-controlled packaging machine, indication cards of time, temperature and quality indices, and on-going cold chain device were developed and applied to extend the shelf life of meat. An instrument for automatic meat quality grading was developed with over 90% accuracy.
In this project, 7 patents and 13 other property rights were authorized, 3 first-or-higher grade prizes of provincial and ministry level award for science and technology progress were achieved. Sixteen standards were drafted. The technology and equipment have been applied in more than 30 meat companies with an increased sale of 19.3 billion RMB. A contribution of the project was to have increased the market share of chilled meat from 1% a decade before to 10% in 2011, and to 30 to 40% in some metropolitan cities, and to a shift of fresh meat consumption from hot-boned meat to chilled meat in China. The general technology of the present project reaches the internationally advanced level.
