Study On Technology Optimization And Microwave Sterilization Of Pasteurized And Restructed Meat Product With Sweet Soybean Paste

Pork cured with sweet soybean paste, with unique flavor and long history, was a traditional meat product and popular with consumers in China. Along with the enhancement of people living standard and the speeds up of the rhythm of life, Pork cured with sweet soybean paste could not satisfy the habit of the modern consumption and losed its competitive ability gradually in the market due to its own disadvantages, such as pollution during production, long processing cycle, instability of the product quality, inconvenience for eating and so on. In view of these above questions, the Rong chang Pig, which produced in Chongqing area was planed to process to the pasteurized and restructured meat product with sweet soybean paste. On the basis of previous studies, the microwave sterilizaton was used to reduce the number of microorganisms in the finished products and reach the shelf life of 2 months under 4 degreesC. So this meat product not only been with the unique flavor of traditional Chinese meat product, but also been with characteristics of health, convenience and pleasant texture and taste of western meat product. The main results were as follow.1. The phenomenon of oil out of meat product was serious according to original formula. So the sucrose ester of fatty acide, compound phosphates and fat adding amount were regarded as the influencing factors, and the sensory scores and the emulsion stability(ES) were the evaluating indicators. Under the Response Surface Methodology, the results indicated that:(1) When taking the sensory scores as evaluating indicator, the sensory scores of the pasteurized and restructured meat product with sweet soybean paste increased with increases in sucrose ester of fatty acide and decreases in fat adding amount. While the Sensory scores was little effectd by compound phosphates. Taken the sensory scores as response value, the regression model was:Y=6.96250+78.50000X₁+97.50000X₂+0.24500X₃-150.00000X₁X₂-1.50000X₁X₃-0.50000X₂X₃+45.00000X₁²-155.00000X₂²-5.500000X₃²(2) When taking the ES as evaluating indicator, the ES value of the pasteurized and restructured meat product with sweet soybean paste increased (the emulsion stability decreased reversely) with increases in fat adding amount. While the ES was little effectd by sucrose ester of fatty acide and compound phosphates. Taken the ES value as response value, the regression model was:Y=9.50750-72.85000X₁-13.07500X₂-0.01525X₃+58.00000X₁X₂+1.12000X₁X₃-0.81000X₂X₃ +147.50000X₁²+34.50000X₂²+0.01165X₃²(3) the optimum formula was, sucrose ester of fatty acide 0.14%, compound phosphates 0.25% and fat adding amount 15%.2. The best formula of the pasteurized and restructured meat product with sweet soybean paste was:the ratio between lean and fat is 8.5 to 1.5, sweet soybean paste 8%, starch 5%, sodium chloride 2.5%, compound phosphates 0.25%, sucrose ester of fatty acide 0.14%, sugar 1%, sodium isoascorbate 0.10%, nitritr 0.013%, monascus red 0.02%, caramel color 0.04%, carrageenan 9%, konjak gum 1.1%, xanthan gum 0.5%, water 4%.3. The microwave power, sterilization time and sample weight were selected as main factors in the single factor experiment and the orthogonal test. (the meat product withou sterilization as the control group) The study found:(1) In the single factor experiment of microwave power,50 g samples were treated for 60 s at 300,400,500,600,700 w and 800 w for 30 d storage at 4 degreesC. Following results were recorded, the aerobic bacterial count of the control group and meat product with 300 w, and the coliform bacteria of the control group and meat product with 300,400 w and 500 w were surpassed the sanitation standard after 30 d. Results also indicated that the microwave power was not a significant effect on protein content, L value, A^* value, B^* value, hardness, springiness and cohesiveness, except core temperature.(2) In the single factor experiment of sterilization time,50 g samples were treated for 30,60,90,120,150 s and 180 s at 600 w for 30 d storage at 4 degreesC. Following results were recorded, the aerobic bacterial count of the control group and the coliform bacteria of the control group and meat product with 30 s were surpassed the sanitation standard after 30 d. Results also indicated that the sterilization time was not a significant effect on core temperature, protein content, L value, A^* value, B^* value, hardness and cohesiveness, except springiness.(3) In the single factor experiment of sample weight,50,100,150,200 g and 250 g samples were treated for 120 s at 600 w for 30 d storage at 4 degreesC. Following results were recorded, the aerobic bacterial count and the coliform bacteria of the meat product of 200 g and 250 g were surpassed the sanitation standard after 30 d. Results also indicated that the sample weigh was not a significant effect on core temperature, protein content, L value, A^* value, B^* value, chewiness, springiness and cohesiveness, except hardness.(4) Through orthogonal test, the optimum technology of microwave sterilization was determined:microwave power 800 w, sterilization time 105 s, sample weight 75 g.4. In the storage test, the control groud (75 g,without sterilization), the meat product (75 g) treated by microwave for 105 s at 800 w, the meat product (75 g) treated by pasteurization for 30 min at 80 degreesC in water, these three groups were stored at 4 degreesC for 60 d. Following results were recorded, the meat product treated by microwave sterilization and pasteurization all met the requirments in terms of the aerobic bacterial count and the coliform bacteria. However, the aerobic bacterial count and the coliform Bacteria of the cotrol groud were surpassed the standard after 60 d. Results also indicated that the pH, water content, TVB-N, color, and TPA of the meat product treated by microwave sterilization were better than that of the meat product treated by pasteurization, except hardness.This study found that, the pasteurized and restructured meat product with sweet soybean paste, with the optimum technology of microwave sterilization, could meet the requirments in terms of microbiological index. And its qualities also were better than the meat product treated by pasteurization.