| Penaeus vannamei was favored by consumers due to its delicious taste but alsohigh nutritional value. Shrimp products sell well in coastal and inland markets.Because of the chilly preservation of healthy conditions or transit system is notperfect and the limit to production, transportation, storage and circulation of shrimp,the Spoilage Organism growth and reproduction will cause spoilage ofproducts.However, the correlation between basic research on Specific spoilageorganisms and parameters of spoilage relatively sparse, so the study of spoilagebacteria changes which in its composition and related spoilage has great practicalsignificance to control quality. In this paper, the chilly fresh shrimp as raw material,was infected by the Spoilage Organism from the fresh shrimp and observe its spoilagequality changes and establish the forecast model.It was provide theoretical basis topredict and protect for the chilly fresh shrimps.(1) We added to identified by means of morphological and biochemical tests, theSL-1,SL-3,SL-4Spoilage Organism isolated from Penaeus vannamei，were belong toPseudoalteromonas sp., Shewanella sp.and Chryseobacterium sp., results wereconsistent to molecule identification. Amino acid decarboxylase experiment showedthat:SL-1,SL-3and SL-4three spoilage organisms has activity of ornithine and laiamino acid decarboxylase, and bacteria, and SL-1and SL-3both have argininedecarboxylase activity again, SL-4bacteria has not l-arginine decarboxylase activity.This methods provided the scientific basis to preserve shrimps fresh and predictionstudy for shelf life. Results show that optimum temperature with the SL-1and SL-3were best between28and31℃, but optimum temperature of SL-4Spoilage Organismwere34℃or so; the most optimum environment for the growth of SL-1and SL-3was pH7-8, but SL-4Spoilage Organism grew best in pH8.(2) Through analysis change regulation of three Spoilage Organism and thespecific quality indexes of shrimp,this indicators include that total number of bacteriaand TVBN, pH, Aw，under273～281K temperature; Finally, it established the firstorder kinetics equation between TVBN and storage time to predict ready-to-use shrimp in a certain temperature under the condition of shelf life. Finally,contrastedwith the shelves of the actual measured value to model of prediction relative error lessthan10%, it shows that the model in practice was practical.（3）This paper established a detection of liquid chromatography-tandem massspectrometry technology (LC-MS/MS) method for an eight kinds of biogenic aminesin the shrimp. Compared with Ethanol, methanol, n-butanol, acetonitrile,0.1%formicacid water and acetonitrile (80:20),0.01mol/L HCl,1%TCA seven solvent on theextraction effect of biogenic amine, add recovery experiment result contrast, select1%TCA as the ideal solvent for extracting effect methodology validation, finallyestablished suitable method for shrimp samples of8kinds of biogenic amines inlaparoscope, and fluided mass extraction method, provided reference. for the precisedetermination of biogenic amines inAquatic Product.（4）Divided shrimp into infected and natural spoilage groups in the temperatureof4℃,8℃,12℃,under the condition of control method,microbes and the sampledetermination of biogenic amines content, analyzed the data that biogenic aminescontent of the spoilage of prawn shrimp in this period of time. We established therelationship that evaluating biogenic amine and microbial spoilage generatingrelationship of shrimp, the correlation analysis results show that the combination ofmicrobial quantity, TVBN and sensory score, the order of spoilage capacity for SL-3>SL-1> SL-4at4℃,8℃,12℃storage conditions; the order of Histamineproduction is:SL-1> SL-4> natural pollution>SL-3; At three different temperaturesduring the process of storage, the best quality indicators correlated with specificmicroorganisms were TVBN, Total biogenic amine, cadaverine, putrescine,histamine. |
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