The Study And Evaluation Of Quality Index On Chilled Pork

Because of rich nutrition,health and safety,welcomed by consumers,chilled pork has gradually become a new consumption pattern.With the improvement of living standards,people are increasingly focusing on meat quality.There are many factors influencing the freshness of chilled pork.Microbial contamination has been considered as a major reason for meat spoilage during storage.Microbial growth and reproduction will induce toxic metabolites such as biogenic amine so that meat becomes unappealing and unsuitable for human consumption.It has become a new research direction which the fresh degree of meat product is defined by the changes of biogenic amine contents.This paper studied the changes of sensory,total bacteria,biogenic amines and smell under different temperature with different packaging respectively analyzed.The spoilage common indicators impacting on the chilled pork were determined,which was based on correlation analysis for quality indicators,then the Logistic model was used to fit the common indictors to reflect the spoilage progress for chilled pork.The study will also provide a theoretical basis for the development of intelligent packaging of index card based on biogenic amines and establish the foundation for quality evaluation of meat.The results showed that:(1)The changes of sensory,total bacteria and biogenic amines(tyramine,putrescine,cadaverine,tyramine,spermidine,spermine),as well as the smell in chilled pork during storage under different temperature(5?,10?,15?,20?,25?)with different packaging(pallet packaging and modified atmosphere packaging:40%O2+40%CO2+20%N2)were not identical.Sensory scores decreased gradually with the prolongation of the time,the higher the temperature,the faster the prolonged decline;total bacteria increased gradually with time,and the higher the temperature the faster increased,and lag period was shorter;the changes of tryptamine,spermidine and spermine in the storage process were litter,but the contents of putrescine and cadaverine rised with the extension of time,and they changed slowly during the early storage,and increased rapidly in the later storage.The electronic nose was applied to analysis the change of odor of chilled pork.The results showed that the odor changed obviously in different temperature and packaged,and the distinction was better,which was consistent with the changes of sensory and total bacteria.(2)Through using principal component analysis on the quality index of chilled pork,the results showed that putrescine,cadaverine,total bacteria,S2,S7 and S9 could reflect the spoilage,process of chilled pork,So putrescine and cadaverine can be regarded as the common indictors with the sensors of S2,S7 and S9 to evaluate the quality of chilled pork.(3)The nonlinear regression procedure of Origin 8.0 statistical soft ware was used to fit the experimental data of putrescine and cadaverine during storage with Logistic models under different temperature with different packaging and used the statistical criteria RSS,MSE,and Adj.R2 to evaluate the fitting ability of all models.The results showed that the ability fitting putrescine was better than cadaverine,so putrescine used to evaluate the quality of chilled pork was more accurate,and determined the threshold of putrescine in pallet and modified atmosphere packaged chilled pork were 0.51?1.50mg/100g,0.46?2.46mg/100g,respectively,which can provide the theory on the basis of development for production and new technology enterprises.