Cinnamon essential oil microcapsule was developed. Microcapsule was prepared with cinnamon oil embedded β-Cyclodextrin (β-CD). The influence of the ratio of core (Cinnamon essential oil) to wall (β-CD), temperature, reaction time and stirring speed on the embedding rate of cinnamon essential oil were studied through L 9 (3 3) orthogonal test. The optimum preparation conditions of cinnamon essential oil microcapsules was as follows: the ratio of core (Cinnamon essential oil) to wall (β-CD) was 1:7, the temperature was 90˚C, the reaction time was 1h and the stirring speed was 1000 r/min, under these conditions, the embedding rate of cinnamon essential oil can reach to 90.24%. When the dosage of cinnamon oil microcapsule was 0.03g/ml, the diameters of inhibition zone on E. coli and Penicillium were up to 36mm and 24mm.

Abstract. The nano silver powder was prepared by liquid phase reduction of silver nitrate solution with ascorbic acid (C6H8O6) as the reducing agent and polyethylene glycol 200 as the dispersant. Through a L9(3 4 ) orthogonal project, the optimum process conditions were determined as follows: the concentration of AgNO3 was 20mg/mL, the amount of polyethylene glycol 200 was 10mL, and n(C6H8O6)/n(AgNO3) was 1:3, the reaction temperature was 60 ℃. Under these conditions, evenly dispersed and high purity nano-silver powder can be prepared. The average particle size of the silver nanoparticles was less than 10 nm by Malvern laser particle size analyzer, TEM and XRD. The antibacterial activity of nano silver powder was tested, and the results showed that when the concentration of nano-silver powder was 10ug/mL, the inhibition zone of E. coli could reach 15mm, and the antibacterial effect was significant.

The cinnamon essential oil micro-capsules was prepared by β-Cyclodextrin (β-CD) embedding technology, the commercially available fruit wax was used as substrate and cinnamon oil micro-capsule was added as antibacterial agent. The concentration of fruit wax, micro-capsules addition, dissolution temperature, stirring speed and other factors on the fresh-keeping effect of antibacterial fruit wax were studied through L9(3 4) orthogonal experiments. The results of orthogonal experiments showed that the antibacterial fruit wax had a significant antibacterial effect on Penicillium and Staphylococcus aureus. The optimum preparation technology was determined as follows: the concentration of fruit wax was 50 % (relative to the total volume of fruit wax solution), the content of cinnamon oil micro-capsules was 40 mg/mL, the dissolution temperature was 70˚C, the stirring speed was 700 r/min, a good antibacterial effect of fruit wax solution can be obtained. The inhibition zone diameter on Penicillium and Staphylococcus aureus was 28 mm and 20 mm. The fresh-keeping effect of the cherry tomato was tested, the results showed that all the indexes of the cherry tomato coated with the anti-bacterial fruit wax were better than the control group, the weight loss rate and respiration intensity were significantly reduced, and its shelf life was significantly extended.