| The Lonicera Caerulea L.contains a variety of active ingredients,with high nutritional value.The pulp of Lonicera Caerulea L.contains a lot of juice,but the skin is easily broken.With the expansion of Lonicera Caerulea L.plant area,the postharst storage of Lonicera Caerulea L.needs to be solved urgently.In this paper,the putrefying bacteria of Lonicera Caerulea L.were isolated and identified,and the Eos with antibacterial effect on putrefying bacteria were screened out.In order to solve the problems of volatile,easy oxidation and short utility time of Eos,plant Eos were embedded by complex condensation method to explore the inhibitory effect of plant Eos microcapsules on main spoilage bacteria of Lonicera Caerulea L.It can provide theoretical basis for practical application of Lonicera Caerulea L.preservative,improve its fresh food market share and reduce transportation cost,at the same time promote the deep processing of Lonicera Caerulea L.industry.（1）In this study,the putrefying bacteria of Lonicera Caerulea L.after natural putrefying were isolated,purified and identified.The three strains were identified as Fusarium sp.,Alternaria tenuissimaand Aspergillus fumigatus.（2）The inhibitory effects of thyme Eo,cinnamon Eo,clove Eo,laurel Eo and oregano Eo on three kinds of spoilage bacteria were investigated by cup-plate method.The results showed that oregano Eo had the best comprehensive inhibition effect,and the inhibition rate was 22%,36% and 23%,respectively.（3）The MIC and MBC of spoilage bacteria were studied with oregano Eo.The results showed that the MIC of oregano Eo inhibit Alternaria tenuissima and Aspergillus fumigatus was 0.4 μL/m L,and Fusarium sp.was 0.3 μL/m L.The MBC of oregano Eo inhibit Alternaria tenuissima was 2.5 μL/m L,for Aspergillus fumigatus and Fusarium sp.was 2.0 μL/m L.The inhibitory effect of oregano Eo on putrefying bacteria（direct contact and fumigation）was further studied.The results showed that oregano Eo could completely inhibit the three kinds of spoilage bacteria at 400 μL/L,400 μL/L,300μL/L,and fumigation at 75 μL/L,87.5 μL/L,75 μL/L,respectively.In conclusion,oregano Eo has a better fumigation effect on spoilage bacteria.（4）In this study,gelatin and acacia gum were selected as wall materials,and oregano Eo was embedded by complex condensation method.The turbidity value of the system was maximized when the optimal wall material ratio was 1:1 and p H 3.9.On this basis,the preparation process of oregano Eo microcapsules was optimized,and the optimized wall material concentration was 1.5%,core material concentration was 0.75%,stirring speed was 450 rpm/min,stirring temperature was 45℃,embedding rate was81.31%,oil carrying rate was 40.5%.The influence of the four factors on the embedding effect of microcapsules as follows: core material concentration > wall material concentration > stirring speed > stirring temperature.（5）The average particle size distribution of microcapsules ranged from 80 to210 nm,and the average particle size was 161 nm,which was uniformly distributed in the suspension.Through microscope observation,it was found that microcapsules rarely adhered,the shape was relatively complete,and the particles were full.Fourier transform infrared spectrum analysis showed part of the vibration peak of oregano essential oil appeared in the oregano essential oil microcapsule,indicating that oregano essential oil was successfully embedded.（6）The antibacterial capacity,antioxidant capacity and sustained-release performance of oregano Eo microcapsules were studied.It was found that oregano Eo microcapsules could completely inhibit the growth of spoilage bacteria when it was used up to 0.02 g.Its can not only better retain its antioxidant capacity,but also resist the adverse effects of the outside on the Eo and reduce the oxidation of the Eo by light.The release rate of oregano Eo microcapsules is about 7% lower than that of oregano Eo in different environments.Comprehensive analysis,this paper focuses on the identification of the main spoilage bacteria of Lonicera Caerulea L.and the optimization of the preparation process of oregano Eo microcapsules and antibacterial test.Alternaria tenuissima,Aspergillus fumigatus and Fusarium sp.were found to be the main spoilage bacteria of Lonicera Caerulea L..Oregano Eo microcapsules had better fumigation inhibition effect on the three spoilage bacteria. |
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