Study On Synthetical Preservation Technology In Pasteurized Poultry Product (Spiced Duck Neck)

Pasteurized poultry Product represent the development tendency of poultry products, but the most pressing problem to be solved is how to extend its shelf-life.In this thesis,taking the case of low temperature duck neck products.The spoilage discipline and mechanisms of low temperature duck neck were summarized on the basis of spoilage bacteria isolation and spoilage microflora analysis. HACCP is established by examining the microbial contamination during process of the Spiced duck neck. The single factor biological inhibitors were chosen and the optimal proportion of the mixture of three kinds of preservatives was successfully investigated and determination of pasteurization techniques. Study on the synthetically preserving techniques of spiced duck's neck. The main results were as follows:(1)the major spoilage bacteria in spiced duck's neck were isolated.the result showed that the main microflora was Brochothrix.secondly, Enterobacter,Pseudomonas . thirdly , Enterococcus,Lactobacillus,Staphylococcus and Micrococcaceae,And a little of mould involves in the spoilage microflora.(2)Storage temperature had no significant effect on microflra component when the spiced duck's neck were stored at 4℃or 25℃. The main microflora survives after pasteurization was anaerobic bacteria,Lactobacillus. secondly, Pseudomonas,Bacillus. thirdly, Staphylococcus and Micrococcaceae. Diffent microflora multiplied during storage,while Bacillus increased most quickly.the two kinds of preservation method prolonged the shelf-life 23days and 44days.(3)HACCP system of spiced duck's neck processing was established.The critical control points were choice and receiving of material meat, pickle, cutting ,marinate,packaging, sterilization and checking of final products.(4)Chitoson ramification what water-soluble carbocymethyl chitoson.the optimum condition of this experiment is: sodium hydroxide concentration 50%,the time of reaction is 3 hours, the temperature of reaction is 50℃. m(CYS):m(chloroactic acid)= 1:4.5;yield 107%;Viseosity 46mpa.s;DS0.74; aqueous solution viscosity of carboxymethyl chitoson in 1%have film forming . N,O-carboxymethyl chitosan had anti-Escherichia coli action . The intensive inhibition activity of N,O-carboxymethyl chitosan on E.coli was observed.( 5 ) the optimal proportion of the mixture of three kinds of preservatives. the total microbial number: Y;N,O-carboxymethyl chitosan:X1; Nisin:X2;ε-polylysine:X3;regress equation:Y=89.398+77.488X1+(-4.477)X2+(-45.46)X3+20.625X1X2+(-53.125)X1X3+ (-5.625)X2X3 +139.458X1X1+128.848X2X2+23.64X3X3(6)the optimal proportion of the mixture of three kinds of preservatives ,the conclusions is: X1=6.26g/kg,X2=0.253g/kg,X3=0.394 g/kg and Ymin=70cfu/g.(7)It is indicated the effect of sterilization by microwave heating(95℃,5min)is better than that of normal heating.the sterilization by microwave heating prolonges the shelf-life 20～25days.(8)the result of synthetical preservation (HACCP system of spiced duck's neck processing , the optimal proportion of the mixture of three kinds of preservatives and sterilization by microwave heating)studies showed that the shelf-life of spiced duck's neck could be ectended to 90days at 4℃or 50days at 25℃.