| Active packaging has gradually become a key subject in the research field with the development of social economy and the mode transformation of mass consumption,especially the usage of natural modifier(plant oils,natural extract etc.),which is becoming one of the hot research direction.These natural ingredients are safe,non irritating,high stability and most of the ingredients have broad-spectrum antibacterial ability and strong antioxidant properties.Therefore,by adding functional natural ingredients to produce packaging materials with a specific purpose give the function versatility to ordinary packaging substrate model.And the active packaging has become the new creative and attractive packaging form.These active packaging materials or system provide the basic role for the packaged food.Meanwhile,they play its unique functions,which extend the shelf life of food and provides a reliable guarantee for consumer health.In this paper,ethylene-vinyl alcohol(EVOH)copolymer was used as the film substrate,nano-montmorillonite(MMT)acted as modifier,geraniol(Ger)andα-terpineol(Ter)served as the active bacteriostatic agents to explore the active bacteriostatic packaging research.EVOH/Ger and EVOH/Ter were obtained by extrusion blow molding with 94%(wt%)EVOH resin as packaging film substrate,with6%(wt%)of Ger and 6%(wt%)of Ter as active bacteriostatic agent respectively.Then the EVOH resin was still used as the packaging film substrate with the MMT material added in with the mass fraction of 3%,and then the secondary granulation process was studied by twin-screw extruder.Then the mass fraction of 6% Ger,6% Ter and mass fraction(3%+3%)were added into the modified EVOH resin masterbatch to prepare the nano-active antibacterial packaging film,EVOH / MMT / Ger,EVOH / MMT / Ter and EVOH / MMT / Ter/Ger with the extrusion blow molding process.The basic properties of the modified films were tested,including mechanical properties,optical properties,thermal stability,scanning electron microscopy and other properties of the film.Especially tested the antibacterial and oxidation resistance of the active EVOH packaging film.In addition,under the condition of refrigerated(4 ± 1)℃,the preservation effect of prepared EVOH fresh-keeping films on snakehead slices were studied.The main conclusions are as follows:(1)EVOH/Ger and EVOH/Ter,which made EVOH packaging films have better gas(O2)barrier properties and thermal stability.However,the modified action to EVOH resin has promoted the flexibility,decreased rigidity(tensile strength)and has no adverse effect on the water vapor permeability.In addition,the EVOH packaging film modified by active agent had certain bacteriostatic effect,and had obvious inhibitory effect on Escherichia coli,Salmonella and Listeria monocytogenes,and the antibacterial effect of the EVOH/Ger sample film was slightly better than that of the EVOH/Ter.The characteristics of geraniol and α-terpineol,which made the modified EVOH packaging films possessed antioxidant properties.In addition,the antioxidant properties of EVOH/Ter were better than that of EVOH/Ger.At the same time,the inherent transparency of the EVOH film material slightly decreased after the addition.(2)Research results show that MMT,antimicrobial agents(Ger,Ter)are components have good compatibility with EVOH resin,and can buffer the decomposition of EVOH trend.By adding MMT,not only enhanced the mechanical properties of EVOH film materials,and the flexibility also was enhanced;In addition,the modification of EVOH resin reduced the water vapor transmission rate but enhanced the oxygen barrier property.On the other hand,due to the inherent characteristics of the MMT material,the transparency of the EVOH film was decreased.After modification with MMT,the antibacterial property of EVOH packaging film was improved than those films,which were modified only by the Ger or Ter.Such as sample EVOH/MMT/Ger could inhibit the growth of E.coil and L.monocytogenes about 3.84 and 5.49 log,respectively and compared with the sample EVOH/Ger(chapter 3.2.4),the inhibitory effect were higher than 1.82 and 4.49 log.In addition,film sample,which added 3% Ger and 3% Ter also showed a significant antibacterial effect with inhibitingthe growth of E.coil,S.enterica and L.monocytogenes about 3.37,1.97 and 3.66 log,respectively.With the addition of two kinds of active components,the nano-active EVOH film has antioxidant properties and the sample EVOH/MMT/Ger/Ter has stronger synergistic antioxidant effect.(3)The snakehead slices were choosen as the freshness-keeping research object,and the content of total volatile basic nitrogen(TVB-N),the total number of colonies(TVC),pH value,thiobarbituric acid(TBA)value,water holding rate are the freshness indexes to evaluate the effect of modified EVOH packaging films.The test data of fish samples showed that the modified EVOH packaging films had significant effect on preservation.If take the TVC index(107 CFU/g)as for the edible standard and combined with other relative freshness indexes,each EVOH packaging film could effectively prolong the shelf life of fish about 4 ~ 5 days.The effect of nano-active EVOH packaging film was better than that of active EVOH packaging membrane,which was modified only by Ter or Ger.This experiment showed that two kinds of active antibacterial agent both can be applied to the preservation of fish products.Not only they are safe and non-toxic,and have obvious antiseptic effect with characteristic of natural extraction and retarding the rapid oxidation action of organic lipid composition,and they have great market application values.(4)This study has certain scientific reference value at a certain extent,but also has some shortcomings,such as the transparency of the modified EVOH films decreased.In addition,those films attached the smell of natural active antibacterial ingredients slightly and may have some influence on the original taste of food,which were packaged by them. 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