Study On The Technology For Separating Grape Seeds Oil And Procyanidins From Grape Seeds

Grape seeds contain quantitative grape seeds oil (GSO) and procyanidins (PCs). GSO is rich on unsaturated fatty acids such as linoleic acid which is used to prevent and treat hypertension, arterioscleroses and heart disease. PCs possesses a variety of physiological activities such as antioxidant. It is one of the most popular herbal medicines in the world. Consequently, it must be realistic and meaningful to seek an appropriate method to extract GSO and PCs from grape seeds.In this thesis, the scale- up of the supercritical fluid extraction (SFE) process for extracting GSO and PCs from grape seeds were separately studied on the basis of the previous research results obtained by the other members of our lab. Subsequently, flacculation technology was employed to better the PCs extracts' solubility in water by ridding impurities in it. In addition, process for extracting PCs from grape seeds through water leaching and removing impurities by alcohol was also studied. At last, the experimental results of the extraction process of PCs were simulated using artificial neural network.The process of extracting oil from grape seeds was firstly studied using a 25L SC-CO2 extraction plant. The yield of GSO in this experiment was found to be 13.87%, which is close to 13.51% in the lab-scale experiment. Extracting procyanidins were further studied from the remains after extracting oil from grape seeds using the SC-CO2 circulation plant with 1L scale . Three kinds of methods for adding co-solvent were investigated and static mode was selected for scale-up experiment. Orthogonal test was designed in order to find the suitable parameters. The experimental results show that the yield of 8.38% with the high purity above 95% of procyanidins can be obtained under the investigated optimal conditions of pressure of 35MPa and temperature of 65oC.In order to improve the quality of procyanidins and to reduce the content of water insoluble substances in procyanidins to the level of less than 5%, the flocculation technology was employed. The influnces of flacculation temperature, concentration of the flacculant and concentration of PCs on the the yield, purity and solubility in water have been investigated and the optimal flocculation conditions were finally determined. The experimental results show that procyanidins with high purity above 95% while the content of water insoluble substances less than 2.81% can be obtained after flocculation operations under suitable coditions.In addition, another series of experiments to extract PCs from grape seeds through water leaching and removing impurities by alcohol were conducted. PCs with the purity of 62.24% was first extracted out from grape seeds with the yield of 11.13% via water leaching. Then, its purity was further improved to 82.21% with the yield of 73.92% through removing impurities by alcohol. These experiments provide data for the subsequent research on the macro-resin adsorption process.At last, the results of the process for the extraction of PCs were successfully simulated with a "2-N-2" artificial neural network. After logical training, the network error decreased to 1.49% and the maximum of sample error is 3.42%.