Zanthoxylum Bungeanum Maxim Essential Oil Microcapsules Preparation And Properties Study

Zanthoxylum bungeanum Maxim is a natural medicinal and edible plant,and its whole grass can be used as medicine.The essential oil extracted from the peel,stem and leaves of Zanthoxylum bungeanum Maxim not only can effectively inhibit the growth of bacteria,anti-oxidation and relieve pain,but also has pure,environmental friendly,efficient and safe characteristics,making it have great development potential in various industries.However,because Zanthoxylum bungeanum Maxim essential oil is volatile,insoluble in water,unstable in nature,difficult to preserve and handle,which makes its application in various fields is limited.In this project,one or more natural green materials were selected as wall materials,and the microcapsule embedding technology was used to embed Zanthoxylum bungeanum Maxim essential oil,the process conditions were optimized by embedding rate and yield,and the microcapsules of the prepared Zanthoxylum anthoxylum essential oil were characterized and related performance tests.The main findings are as follows:(1)With β-cyclodextrin,gelatin/gum arabic,soy protein isolate/sodium dodecyl sulfate,sodium octenyl succinate starch/maltodextrin,chitosan,ethyl cellulose,soy protein isolate/gum arabic/maltodextrin as the wall materials,Zanthoxylum bungeanum Maxim essential oil microcapsules were prepared by one or two methods of saturated aqueous solution method,complex coacervation method,spray drying method,emulsification crosslinking method,and evaporation solvent method.The embedding rate and yield of various peppercorn essential oil microcapsules was determined by the UVVis spectrophotometer,the morphology of them were also characterized.It was found that the soybean protein isolate/gum arabic/maltodextrin-Zanthoxylum essential oil microcapsules prepared by spray drying not only had high embedding rate and yield,but also had good morphology.More importantly,the spray drying method is simple and time-saving,and easier to realize the large-scale production and industrialization compared with the others.(2)Using soybean protein isolate/gum arabic/maltodextrin as the wall material,and the embedding rate and yield as main indicators,the preparation process conditions were optimized by single-factor experiment and orthogonal experiment.The results showed that the optimal formulation conditions were soybean protein isolate:gum arabic:maltodextrin = 2:5:3,core-to-wall ratio 2:20,total solid content 10%.The optimal spray drying parameters are air inlet temperature 170 ℃,feed rate 10 r/min,atomizer frequency150 Hz.Under the optimal preparation conditions,light yellow solid powder product was obtained with the embedding rate and yield of the microcapsules were 95.38% and70.54%,respectively.Further antibacterial experiments found that although Zanthoxylum bungeanum Maxim essential oil had the effect of inhibiting the growth of Escherichia coli,compared with Zanthoxylum bungeanum Maxim essential oil,the inhibition effect of microcapsules on Escherichia coli was relatively weak due to its lower essential oil content or sustained release performance was relatively slow.Through the sustained release experiments,it was also found that after microencapsulation,the Zanthoxylum bungeanum Maxim essential oil had good sustained release performance in artificial simulated gastric juices and food simulation systems.(3)Double-layer Zanthoxylum bungeanum Maxim essential oil microcapsules were prepared by spray drying method with resistant starch-soybean protein isolate/gum arabic/maltodextrin,attapulgate-soybean protein isolate/gum arabic/maltodextrin and β-cyclodextrin-soybean protein isolate/gum arabic/maltodextrin.The sustained release performance of three kinds of double-layer Zanthoxylum bungeanum Maxim essential oil microcapsules was tested in artificial simulated gastric fluid environment and four different food simulation systems.The results showed that the sustained release effect of the double-layer microcapsules was good.In this work,through the microencapsulation of Zanthoxylum bungeanum Maxim essential oil,on the one hand,the volatile liquid Zanthoxylum bungeanum Maxim essential oil is transformed into solid substance,which solves the problems of volatile essential oil,short shelf life and inconvenient transportation.On the other hand,after microencapsulation,Zanthoxylum bungeanum Maxim essential oil has better thermal stability and good slow-release effect,which expands the application range of Zanthoxylum bungeanum Maxim essential oil.