Preparation Of Different Delivery Systems Of Cinnamon Oil And Its Application In Orange Juice Beverage

Cinnamon oil is a kind of plant essential oil which possesses a variety of biological activities,such as hypoglycemic,anti-inflammatory,analgesic,anti-cancer,anti-tumor and bacteriostatic functions.However,its application is limited in all walks of life due to its disadvantages,such as poor water solubility,easy volatile and oxidation.In order to improve this situation,cinnamon oil liposome and double-layer emulsion were constructed using emulsifiers,which were complex of whey protein isolate（WPI）and stevia glycoside（STE）,to enhance its stability and acceptability.After the optimization of the preparation process,quality evaluation of the two delivery systems were carried out and its vitro simulate digestion,release and bacteriostasis were also studied.The cinnamon oil double-layer emulsion was successfully employed in the preparation of beverage products.The main contents and conclusions of this paper are as follows:Construction of cinnamon oil delivery systems.Particle size,polydispersity index（PDI）and encapsulation ratio（EE）were used as indexes in optimizing the preparation process of cinnamon liposome.The optimized conditions were as follows:the volume fraction of cinnamon oil was 0.41%,the volume fraction of composite emulsifier was5.5%,the volume ratio of WPI solution and STE solution was 1.2:1,and the response surface fitting equation was:Y=81.79+3.47A-0.98B+3.19C-7.46A²-3.83B²+2.24C²+2.04AB-6.51AC+1.86BC,which predicted value of EE was close to the actual measured value（84.2%）.Particle size,PDI and emulsion stability index（ESI）were also used as indexes in optimizing the preparation process of cinnamon oil double-layer emulsion.The optimized conditions were as follows:the mass concentration of WPI was 0.025 g/m L,the mass concentration of STE was 0.008 g/m L,volume ratio of primary emulsion and STE solution was 4:6.Under these conditions,the ESI（8994.15min）of cinnamon oil double-layer emulsion prepared was close to the predicted value,and the fitting equation was:Y=53.94-1491.54A+78.97B+1602.21C+1146.14A²-959.37B²+1826.64C²+545.06AB-2866.62AC+143.95BC.Evaluation of cinnamon oil liposome and double-layer emulsion.TEM images showed that the droplets of the two kinds of delivery systems were spherical and evenly distributed.The average particle size of cinnamon oil liposome was 122 nm and PDI was 0.14,and the average particle size of cinnamon oil double-layer emulsion was 220nm and PDI was 0.16.FT-IR spectra revealed that no chemical changes occurred during the preparation of liposome and double-layer emulsion.The stability test results indicated that room temperature or low temperature would benefit the storage of cinnamon oil delivery system.Both cold-hot cycling and ionic strength will lead to the change of particle size and PDI,which gives rise to the instability of the system.The particle size and PDI of the two delivery systems at p H 5 were larger and higher than those at other p H conditions.Investigation of simulated digestion and release in vitro.Particle size,potential and inverted fluorescence microscopy showed that the changes of the two delivery systems were not obvious in oral or gastric digestion stage,but obviously large droplets and remarkable demulsification occurred in intestinal digestion stage.In vitro release results showed that the release rates of the two delivery systems in SIF were higher than those in SGF.The release kinetics equation of cinnamon oil liposome in SGF was fitted for Weibull distribution equation which was Q=1-(45.533e^-t-e^3.814),R²=0.934.The release kinetics equation in SIF was fitted for Retger-peppas equation which was Q=22.577t^0.390,R²=0.948.The release kinetics equation of cinnamon oil double-layer emulsion in SGF was fitted for Retger-peppas equation which was Q=10.518t^0.460,R²=0.922,and the release kinetics equation in SIF was fitted for Weibull distribution equation which was Q=1-(70.865e^-t-e^4.142),R²=0.930.Investigation of the bacteriostasis of different cinnamon oil delivery systems.The results of bacteriostatic circle showed that cinnamon oil and the two cinnamon oil delivery systems had the strongest inhibitory effect on L.monocytogenes,but no significant difference on E.coli and S.aureus.The minimum inhibitory concentration（MIC）of cinnamon oil liposome against the three bacteria was 0.513μL/m L,the minimum bactericidal concentration（MBC）against E.coli and S.aureus was 1.025μL/m L,and the MBC against L.monocytogenes was 0.513μL/m L.The MIC of cinnamon oil double-layer emulsion against the three kinds of bacteria was 0.391μL/m L,MBC against E.coli and S.aureus was 0.781μL/m L,and MBC against L.monocytogenes was 0.391μL/m L.Through analysis of cell permeability and scanning electron microscopy observation,it was found that the two cinnamon oil delivery systems could lead to the leakage of nucleic acid,protein,alkaline phosphatase and superoxide dismutase,which affected the normal growth and metabolism of cells,and the appearance of bacterial cells,such as the forming of corrugation and rupture.Application of cinnamon oil double-layer emulsion in orange juice beverage.With sensory score as the index,the single factor experiment and orthogonal experiment were carried out in optimizing the orange juice beverage.The optimal formula was consisted of 60%of orange juice,3.0%of cinnamon oil double-layer emulsion,2%of granulated sugar and 0.04%of citric acid.The sensory score of the orange juice beverage prepared with the optimal formula was 9.52 points,and the beverage exhibited the best taste in consistent with the comprehensive evaluation while its centrifugal precipitation rate was 5.4%within 48 h,indicating good stability.The browning index of the beverage was lower than that of blank control group,which resulted to delaying the browning of beverage.