Construction Of Cinnamon Essential Oil Emulsion Delivery System And Its Effect On Fruits And Vegetables Storage Quality

Due to its strong regional and seasonal nature,fruits and vegetables have a short shelf life during harvesting and are prone to spoilage.Chemical preservatives commonly used in fruit and vegetable preservation have potential harm to human health.Therefore,it is of great significance to find active substances from natural sources as effective ingredients for the preservation of fruits and vegetables.As a natural preservative,plant essential oils have good antibacterial and antioxidant functions.However,their wide application in food is limited by their poor water-solubility and stability.Based on this,this project used an emulsion delivery system to solve the problems of low water solubility and instability of essential oil,and applied it to preserve apple juice and mango.The results are as follows:1.The individual cinnamon oil nanoemulsion showed 80%-90% inhibition of PPO activity,but it was not enough to effectively control the browning of apple juice.The0.05% w/v ascorbic acid effectively inhibited the browning of apple juice for 24 h.After 27 h,the ascorbic acid was exhausted and could not maintain the color of apple juice.When cinnamon essential oil nanoemulsion was used as polyphenol oxidase inhibitor and ascorbic acid as reducing agent,the color of apple juice was effectively maintained at 4 °C for 48 h.When the concentration of cinnamon essential oil nanoemulsion reached 0.2% v/v,the stability of apple juice was significantly improved.In addition,the combined treatment delayed the degradation of total phenol content and ascorbic acid content in apple juice.Therefore,the combination of cinnamon essential oil nanoemulsion and ascorbic acid can enhance the inhibition of enzymatic browning and maintain the quality of cloudy apple juice.2.The cinnamon essential oil Pickering emulsion coating(CH-PE)was prepared with cellulose nanocrystals as emulsifier,and its preservation effect on mango was studied.It was compared with cinnamon essential oil emulsion coating(CH-E)prepared by commonly used emulsifier Tween 80.The results showed that CH-PE coating had lower water solubility and water vapor permeability than CH-E coating,and CH-PE coating had better sustained-release performance for cinnamon essential oil.In the control group,mangoes lost edible value after 12 days of storage at 25 °C,with yellow peels and large areas of dark spots.The hardness,titratable acid content and ascorbic acid content decreased to 70.792 g,0.074% and 14.42 mg/100 g,respectively.And the activities of polyphenol oxidase,pectin methyl esterase and polygalacturonase in the samples were relatively high.Compared with CH coating group and CH-E coating group,CH-PE coating group had the best preservation effect.During 12 days of storage,the mango kept good appearance without obvious black spots.The hardness,titratable acid and ascorbic acid contents were 313.833 g,0.97%and 23.39 mg/100 g,respectively.The activities of polyphenol oxidase,pectin methyl esterase and polygalacturonase in the samples of CH-PE coating treatment group were significantly inhibited.Therefore,the cinnamon essential oil Pickering emulsion coating could maintain the storage quality of mangoes and prolong the shelf life of mangoes by inhibiting enzymatic browning and cell wall degradation.