Study On Extraction And Application Of Functional Components Of Jujube Kernel

Jujube kernel is a mature seed of dried jujube plants.It belongs to the genus Rhamnoides.It is a traditional Chinese medicine with homologous medicine and food.The main chemical components are: jujube kernel oil,total flavonoids,polysaccharides,three oxaloids and saponins,etc.Jujube kernel is mainly used to treat diseases such as irritability,insomnia and convulsions.Because jujube kernel is rich in nutrients and active ingredients,it has high economic value for the development and utilization of jujube kernel resources.In this paper,the extraction and application of the two active constituents,jujube kernel oil and total flavonoids were studied.The extraction conditions of jujube kernel oil and the optimization of extraction parameters were optimized.The best extraction process was obtained and obtained by gas chromatography.The fatty acid composition of jujube kernel oil was compared and analyzed.Jujube kernel oil was embedded in micro-capsule technology in applied research.The preparation of composite membranes by total flavonoids of jujube kernel provides basic data and technical support for the research and development of food active packaging membranes and the expansion of their application range.The specific research contents are as follows:Soxhlet extraction is used to extract jujube kernel oil.Taking dried jujube kernel as raw material and petroleum ether as extraction solvent,the factors such as solid-liquid ratio,extraction temperature and extraction time were investigated experimentally,and corresponding orthogonal experiments were designed to obtain the best extraction process of jujube kernel oil condition.Through the range analysis,the order of the factors affecting the yield of jujube kernel oil is extraction temperature,extraction time and solid-liquid ratio.The optimum extraction process of jujube kernel oil was extraction temperature 60?,extraction time 5 h,solid-liquid ratio 3:80(g/mL),the oil extraction rate of jujube kernel was 32.99%.Preparation and characterization of jujube kernel oil microcapsules.Microwave-assisted extraction of jujube kernel oil was carried out,and the fatty acid composition of jujube kernel oil was analyzed.Seven fatty acid components were detected by gas chromatography-mass spectrometry(GC-MS),and the content of unsaturated fatty acid was 80.758%.The saturated fatty acid content was 56.375%.Compared with the extraction methods described in other literatures,the quality of jujube kernel oil was slightly improved,with oleic acid content of 56.375% and linoleic acid content of 24.174%.The ?-cyclodextrin and soy protein isolate were used as the wall material,and the jujube kernel oil was used as the core material.The jujube kernel oil microcapsules were prepared by spray drying method,and the embedding rate was67.54%.Through the analysis of the structure and morphology of the jujube kernel oil microcapsules,it can be seen from the SEM image that the microcapsule particles are intact in morphology.DSC analysis shows that the product properties are stable at room temperature,and the absorption peaks of related groups in the infrared spectrum are weakened or disappeared.The jujube kernel oil has been well microencapsulated.The jujube kernel oil microencapsulated product can reduce the contact between the jujube kernel oil and air and sunlight,and improve the stability of the core material.Optimization of solvothermal extraction of total flavonoids from jujube kernel by response surface methodology.The defatted jujube kernel powder is used as a raw material,and the total flavonoids in the jujube kernel are extracted by solvothermal method.The single factor,liquid-to-liquid ratio,ethanol volume fraction,extraction temperature and extraction time which affect the extraction rate of total flavonoids were investigated.Based on this,the corresponding response surface test was designed.The regression model was established to obtain the best process.The flavonoid extraction rate was 16.761 mg/g.Preparation and study of chitosan/sucrose jujube flavonoids composite membrane.The chitosan composite membrane containing different proportions of jujube flavonoid extract was prepared by casting method.The composite membrane was tested for its properties,including the physical properties of the composite membrane: thickness,density and transparency.The mechanical properties of the composite membrane:tensile strength.And elongation at break;the structure of the composite membrane was characterized by total reflection-Fourier infrared spectroscopy(ATR-FTIR),X-ray diffraction(XRD)and scanning electron microscopy(SEM).The experimental results fully indicate that the addition amount of different flavonoids of jujube kernel extract affects the physical properties and mechanical properties of the composite membrane.Among them,tensile strength,elongation at break and transparency all showed a tendency to gradually decrease.In addition,it can be seen from the infrared spectrumthat the basic skeleton of the chitosan molecule did not change during the film formation process.X-ray diffraction analysis showed that the crystal structure of the chitosan composite membrane was destroyed.SEM analysis confirmed that total flavonoids were accumulated on the surface of the composite membrane.The interaction between chitosan and jujube kernel and the content of active ingredient of jujube kernel had certain influence on chitosan film as food packaging.