Preparation Of Montmorillonite-clove Essential Oil Hybrid Antimicrobial Material And Its Application In Abalone Preservation

In recent years,nanomaterials have been applied to various fields,such as the preparation of slow-release pesticides,encapsulation and delivery of targeted drugs,encapsulation,and release of active cosmetic ingredients,and controlled release of food preservation active components.The loading and delivery of nanomaterials have received wide attention.Aquatic products are an indispensable part of people’s dietary structure and are highly susceptible to spoilage by microorganisms and endogenous enzymes due to the environment in which they are located.Active antimicrobial materials are prepared by encapsulating the active ingredients with nanomaterials,and the encapsulated antimicrobial materials are applied to the field of aquatic product preservation with relatively good performance.In this study,hybrid antimicrobial materials with clove essential oil(CEO)intercalated with montmorillonite(MMT)were prepared using a simple and novel cryogenic ball milling technique,and the thermal stability and loading effects of the hybrid antimicrobial materials(BM-MMT-CEO)Prepared by cryogenic ball milling were compared with those of the manually milled antimicrobial materials(MIX-MMT-CEO).The prepared BM-MMT-CEO was blended with thermoplastic starch(TPS),poly(lactic acid)(PLA),and poly(succinic acidterephthalic acid)(PBAT)at an addition rate of 7 wt%,and the active packaging films were prepared by melt extrusion flow casting.The effects of the addition of the hybrid antimicrobial materials on the basic properties of the films,the mechanism of controlled release of the active ingredients by the antimicrobial carriers,and the effects of the active packaging films on the preservation effect of abalone were investigated.The main research contents and results are as follows.(1)MMT-loaded CEO hybrid antimicrobial materials were prepared by cryogenic ball milling,and the encapsulation effects of BM-MMT-CEO hybrid antimicrobial materials were characterized,including particle size distribution,essential oil loading efficiency,intercalation effect,material structure,thermal stability,and FTIR of the antimicrobial materials.The results showed that the cryogenic ball milling intercalated the CEO into the interlayer space of MMT,resulting in an increase in the interlayer spacing;the BM-MMT-CEO hybrid antimicrobial material obtained by cryogenic ball milling was thermally stable and could effectively protect the active ingredient from damage,and the loading of CEO by MMT was 15.84% and the encapsulation rate was52.82%.the addition of CEO conferred excellent antimicrobial and antioxidant properties to the MMT.(2)The BM-MMT-CEO hybrid antimicrobial material obtained from the above cryogenic ball milling was blended with PLA,PBAT,and TPS by co-extrusion and casting to prepare degradable active slow-release packaging films,and the films were characterized for relevant properties,including mechanical properties,optical properties,barrier properties,surface structure,antimicrobial properties,antioxidant properties,release kinetics,and FTIR.The results showed that there was relatively good compatibility between PLA/PBAT/TPS and the added MMT and CEO,and the mechanical properties and barrier properties of the films were improved after the addition of BM-MMT-CEO hybrid antimicrobial material,with no significant changes in optical properties,the film surface became rougher,and the antimicrobial effect was improved,and the DPPH radical scavenging rate reached 95.4%.The results showed that the release of active substances from the TPS-PLA-PBAT-based films prepared with BM-MMTCEO hybrid antimicrobial material was in accordance with Fick’s law and had a slowrelease effect.It effectively prolongs the release time of active ingredients and reduces the loss of active substances.(3)The TPS-PLA-PBAT-based active packaging films prepared above were used for abalone preservation to evaluate their effectiveness in aquatic product preservation.The physicochemical indexes such as p H,TVC,TVBN,TBARS,texture,and sensory evaluation of the abalone meat during the preservation process were measured separately,and the preservation effect of the films was evaluated in combination with the film release kinetics.The results showed that CEO had better antibacterial and antioxidant properties to prevent lipid oxidation and protein degradation of abalone and ensure the quality of abalone.The abalone meat packed in the bare group,blank film(TPP)started to spoil on the 12 th day,the abalone packed with film added with CEO(CEO-TPP)and film added with manually milled antimicrobial material(MIX-MMT-CEO-TPP)started to spoil around the 15 th day,while the abalone packed with film added with BM-MMTCEO hybridized antimicrobial material(BM-MMT-CEO-TPP)deteriorated to the inedible standard on the 18 th day.The freshness of the abalone was corroborated by the film release kinetics.Abalone packed with TPS-PLA-PBAT-based film(BM-MMTCEO-TPP)supplemented with BM-MMT-CEO hybrid antimicrobial material had a better preservation effect relative to the other groups of abalone,and its shelf life was extended by 6-7 days.