Research On The Extraction Methods And The Technological Conditions Of Volatile Oil From Disospylos Koki Leaves

A study on the extraction of natural flavor from Disspylos koki leave or fruit was carried out. Disospylos koki leaves in our campus were used as raw material to extract the volatile oil,by using the steam distilliation,the solvent method combined with the supercritical carbon dioxide techniques.It is of great value to accelerate the development of the economy.and it also increase the annual income of the tamers.The thesis emhphasis on the steam distilliation,the solvent method combined with the supercritical carbon dioxide(SCCO₂) techniques to extract essential oil,concrete and absolute using Disospylos koki leaves as raw materials. During the first phase,using dried Disospylos . koki leaves as raw materials,beforehand experiments,orthogonal experiments and extraction condition of the steam distilliation have been done.Based on these experiments,the best technical condition of the steam distilliation have been decided.Then many factors such as lixiviating solvent,the granularity of the peel,solid-to-liquid rate ,and extraction time was studied in detail in solent method.According to the experimental data,the optimum parameters of solvent method have been decided.The same way as solvent method ,by carried out a lot of experiments including orthogonal experiments of extraction of essential oil.many factors and optimum parameters of SCCO₂ technique have also been decided.Industrialization of volatile oil was based on the optimum parameter that had been got from the above technics.To face the demand of volatile oil manufactory,whose products are using as semi-manufactreed goods,SCCO₂ technique is also used to refine the volatile oil.From the data of the above experiments,we come to conclusion that the optimum parameters of the solvent method could be obtained by added in 8 times water , dipped for 1.0h, stirred for 20 min,then steam distilled for 2h.The result of determination of different growing period and storing period shows that the highest yield of essential oil is on October and using dry sample during the storing period the yield of essential oil have been decreased from 3.71%(0 month) to 2.13%(12 months). The extraction of volatile oil from Diospyros kaki leaves by stirring method at the same time refluxing.The best extraction technological condition of the solvent method is the 60 degree and the 1:15 ratio of solid and liquid for 2.5h at the first extraction and 1.5h at the second by solvent of 95% ethanol. The optimum parameters of SCCOt technique are extraction pressure 18 MPa,extraction temperature 50°C and CO2 flux 20kg/h.The integral refine optimum parameters of SCCO2 technique are also decided in the paper.According to the results of experiments,the methods of extraction volatile oil from Disospylos koki leaves is feasible!The essential oil has faint scent of Disospylos koki leaves and the concrete and absolute has high quilty and purity flavor of Diospyros kaki fruid. When added a little this natural flavor into the beverage ,it would be very usedful to improve the flavour of the drinking.lt could be a good spice used as perfume in drink and would be a new resource of natural fragrance and flavor with high economic volue.