Establishment Of Sustained Release System Of Ginger Essential Oil And Its Application In Fruits And Vegetables Preservation

Ginger essential oil,as a natural antibacterial agent,has antioxidant and antibacterial properties.However,it has some disadvantages such as volatile,insoluble in water and poor stability.So,two kinds of ginger essential oil embedding systems were prepared by microencapsulation technology and micro-emulsification technology,and then we evaluated the stability,control-release properties and preservation ability of embedding systems.The main research results are as follows:The polysaccharide-based ginger essential oil microcapsules with different ratio of wall material were prepared by complex coagulation method.When the mass ratio of chitosan to sodium carboxymethyl cellulose was 1 ? 1,the prepared microcapsules had stable chemical structure,the best elongation,the lowest crystallinity,the highest content of characteristic components,embedding rate was 88.5%.And it could control the release of ginger essential oil effectively.Under the room temperature/low temperature environment,ginger essential oil microcapsule treatment could improve the firmness,crunchy and antioxidant activity of winter jujube during storage.And it inhibited the increase of red index,maintained the high content of total soluble solids and titratable acid,inhibited the development process of mature and aging,reduced the decay which caused by microbial infection,prolong the shelf life of jujube.Different mass concentrations of ginger essential oil(0%?0.1%?0.3%?0.5%)chitosan nanoemulsions were prepared by ultrasonic and high-pressure homogenization,and then the corresponding edible films were prepared by salivation method.The nanoemulsion has good viscosity,particle size distribution and stability.It also showed the ability of controlrelease regardless of the ginger essential oil content.Edible film has good optical,mechanical properties and structural stability.Ginger essential oilchitosan edible film has better anti-ultraviolet aging and anti-ultraviolet ability compare to the single chitosan edible film.When the content of ginger essential oil was 0.3% or 0.5%,the particle size distribution and system stability of chitosan-based nanoemulsion could be improved.Chitosan edible film can maintain the original firmness,toughness,crunchiness and color of fresh-cut sweet potatoes.The combined treatment of ginger essential oil and chitosan could significantly reduce the number of yeast,mold and total plate count in sweet potato slices(P<0.05).The contents of titratable acid and soluble solids in sweet potato were significantly inhibited(P<0.05)by added 0.3% and 0.5% of ginger essential oil.Compared with 0.1% Ginger EO and 0.3% Ginger EO,0.5% Ginger EO treatment significantly decreased the sensory quality(flavor and overall acceptability)of sweet potatoes(P<0.05).To sum up,the structure of microcapsule/nanoemulsion embedding system has the excellent stable structure and the ability of control-release,which could improve the utilization rate and stability of ginger essential oil,significantly improve the postharvest preservation effect of winter jujube/fresh-cut sweet potato.And it has high application value both in the fruit/vegetable preservation and food packaging filed.The results provided theoretical support for further expanding the application of ginger essential oil in food,medicine and other industries.