Extraction Process And Physicochemical Properties In Seed Oil Of Toxicodendron Vernicifluum

Toxicodendron verniciferum is a deciduous tree or shrub, belonging to Toxicodendron genus, Anacardiaceae family. In China, it is one of the most important economic tree species and mainly distributed in Guizhou, Sichuan, Yunnan, Hubei, and Shanxi. It has a cultivation history more than 2000 years. Fat can be extracted from cortices and kernel of the seed. The fat extracted from kernel is in the form of liquid oil under normal temperature. This oil is rich in unsaturated fatty acid in which linoleic acid content is over 60%. Meanwhile, the linoleic acid has a high health-care function, such as blood fat regulation, anti-arteriosclerosis, and decreasing the rate of disease incidence and mortality resulting from coronary heart disease. As an important industrial chemical, seed oil of sumac can also be used for producing bio-diesel. The annual output of seed of T. verniciferum is about 1.6 million tons, most of which has gone unused without any processing. In this thesis, the extraction process, the physical and chemical properties of the seed oil, and the determination and analysis of fatty acid were studied, taking the seeds of Baiyangpi sumac collected in Guizhou province as experimental material. The main results are as folloes.1. The weight of one thousand seeds was 45.10 g, and the weight of one thousand kernels was 26.32 g. The content of oil in kernel was 10.87%.2. The petroleum ether (30℃～60℃) was a good solvent for the extraction of oil because it had extraction characteristics of a high rate, a low water temperature, short time, high solvent recovery, and the oil could be easily separated from the solvent. Analysis indicated that the density of oil was 0.9261, the acid value was 7.96, the iodine value was 137.455, the peroxide value was 5.725, and the saponification value was 195.665.3. Three factors were selected, i.e. sieving, water temperature, and extraction time, as limiting conditions, and the yield of extraction was considered as the evaluation indicator. The best process conditions for extracting the oil through the experiments of single factor and multi-factors were 0.5 mm sieve,57℃of water temperature, and 120 min extraction time. Under this condition, the extraction rate of oil was 26.53%. This process condition was rather stable and reliable proved by several duplicate experiments. 4. From the analysis of the ingredient and content of fatty acid, the oil was shown to mainly consist of the unsaturated fatty acid. The content of unsaturated fatty acids in oil was as high as 84%, the linoleic acid content was 62.55%, the oleic acid content was 18.88%, the content of linolenic acid was 1.50%, and the concentration of palmitoleic acid was 0.94%. Saturated fatty acids were mainly composed of palmitic acid and stearic acid, in which the palm acid content was 11.04%, and the stearin acid content was 3.27%.