Study On Quality Of Chilled Pork Meat With UV-C Treatment And Two Kind Of Natural Preservative

The pork meat is an indispensable animal food in people’s daily life; it can providepeople with all kinds of essential amino acids, vitamins, minerals and trace elements as wellas calories, protein and fat. Be rich in nutrition makes it a good culture medium ofmicroorganism. The deterioration which is easy to happen do harm to human health. With thechanging of consumption concept, more and more attention to food safety and hygiene hasbeen paid. Chilled meat as the mainstream of future fresh meat consumption, to improve itsquality and extend the shelf life is very critical to ensure market supply and the safety offood.In this paper, UV-C irradiation and two kind of natural preservative were used to dealwith the chilled pork meat which were stored at4±1℃, the sensory, physical and chemicalindicator and microbial indicator of the meat during storage were for used as analysis object.Firstly, in order to determine the appropriate level of each approach, different ways were usedon the meat samples for processing. Then through quadratic general rotational combinationdesign to screening and determine the optimum combination plan, and to validate its effect,the mainly obtained results were listed as the following:（1） Each of the single treatment such as Ultraviolet irradiation, chitosan and teapolyphenols fresh liquid processing can improve the quality and prolong the shelf life ofchilled pork meat at different level.（2） The UV-C irradiation can eliminate the microorganisms on the surface of the chilledmeat and inhibit the growth of food-borne microorganisms during storage. The preservationeffect was best if the samples were irradiated for60s with irradiation intensity of0.45mw/cm2.The chitosan can play the best comprehensive effect when the concentration is1.5%. Boththe economy and preservation effect of the samples which are treated by1.75%teapolyphenols solution are optimal.（3） In the screening of the optimization composite scheme, regress equation（Y=22.302-0.974X₁-0.433X₂+0.696X₃+1.483X₁²+1.322X₂²+0.756X₃²-0.497X₁X₂-0.056X₁X₃+0.24X₂X₃） is obtained by do three factors quadratic general rotational combination designexperiment and carry out multiple regression analysis on the TVB-N. Through the analysis of single factor effect, the marginal effect and the interaction effect of the regression equation,and consider the synergetic effect between the factors, the optimized composition ofcombined preservative measure is: irradiated for64s with Irradiation intensity of0.45mw/cm2,chitosan is1.57%and tea polyphenols is1.63%. The minimum value of the response was21.89while all the three factors obtaining the optimal value.（4） The effective of the optimization composite scheme has been tested, the resultshowed that the composite preservative can effectively inhibit the growth of themicroorganism on the surface of the chilled pork meat and the rising rate of TVB-N value,TBA value and pH, improve the water holding capacity and the quality of the meat, extendthe shelf life. After18days storage, the physical and chemical indicator and microbialindicator as well as sensory indicator are accord with the requirements of the quality of freshmeat.All of these results suggested that the composite using of UV-C irradiation and twokinds of natural fresh-keeping preservative on chilled pork meat is feasible in improving thequality and extending shelf life.