There are about 27 million mu of tea gardens in China, which can produce more than 800,000 tons of tea seeds per year. The oil content of tea seeds is 30~35%, of which unsaturated fatty acids are as high as 75~85%, which is a good functional vegetable oil. In December 2009, the “Announcement No. 18, 2009 of the Ministry of Health of the People’s Republic of China” officially approved tea seed oil as a new resource food, so the development and utilization prospects are broad. This work uses local resources—tea seeds as the experimental raw material, and uses ultrasonic-assisted water enzymatic method to extract tea seed oil. The dosage of cellulase, protease dosage, ultrasonic time, material-to-liquid ratio, enzymolysis time, enzymatic pH and enzymatic hydrolysis are used to extract tea seed oil. Single-factor test of temperature. Based on single-factor test, SAS8.1 software is used to design a combination experiment of four factors: enzyme compound dosage, enzymatic hydrolysis pH, enzymatic hydrolysis temperature, and enzymatic hydrolysis time. Finally, the response surface method is used to optimize the extraction process conditions. After optimization, the best process conditions are high-pressure cooking for 20 minutes, ultrasonic treatment for 20 minutes, ultrasonic temperature of 60°C, material-liquid ratio 1:5, compound enzyme dosage 1.75%, enzymatic hydrolysis pH4.6, enzymatic hydrolysis temperature 44°C, enzymatic hydrolysis time 6.9h. Under this technological condition, the yield of tea seed oil was 29.88%.
Scientific, advanced and unique:
Based on local tea seed resources, this project uses response surface analysis to optimize the ultrasonic-assisted water enzymatic extraction of tea seed oil. The research technology of this experiment is scientific; the statistical method is comprehensive and accurate; the process parameters are reliable, practical, and have a certain degree of scientificity and advancement. The uniqueness of this work is mainly manifested in the first application of enzyme technology and ultrasonic technology in the extraction of tea seed oil; the first application of response surface analysis to optimize the technological parameters of ultrasonic-assisted water enzymatic extraction of tea seed oil; selection of multiple enzymes In order to reduce emulsification and facilitate separation, the raw materials are cooked in the early stage.
Overview of the research level of similar topics:
Tea seeds are the seeds of the Camellia spp., a plant in the genus Camellia family. There are about 27 million mu of tea gardens in my country, which can produce more than 800,000 tons of tea seeds each year. Tea seed oil has the effects of preventing and treating cardiovascular diseases, lowering blood fat and cholesterol, and is a high-grade functional vegetable oil. At present, the main methods for extracting oil from vegetable oils are pressing and solvent extraction. However, most oil seeds need to be steamed or roasted before pressing or leaching. The equipment is complicated and the process is cumbersome. Unsaturated fatty acids, vitamin E and other nutrients are severely destroyed after being subjected to high temperature and high pressure; it is easy to cause protein denaturation, so that the cake can not be effectively used after oil extraction, and protein resources are seriously wasted; after solvent leaching, a desolventization process is required, and there are many equipment. Large investment and heavy pollution.
In summary, we should explore a safe, green, and efficient method for extracting plant nutrients. Enzymatic oil extraction technology uses enzymes that degrade the oil tissue to treat the oil on the basis of mechanical crushing. The enzyme further destroys the cell structure to increase the fluidity of the oil in the oil tissue, thereby freeing the oil. Under ultrasonic assisted conditions, enzymatic oil extraction can greatly increase the oil yield and shorten the extraction time. The reason is the strong cavitation effect of ultrasonic waves, which in turn causes turbulence, energy accumulation, perturbation effects and interfaces Effect, to a certain extent, cause certain damage to the plant cytoskeleton and lining, which is conducive to enzymatic hydrolysis. In the process of ultrasonic assisted oil extraction, it will not destroy the thermally unstable and easily oxidized components in the oil, and it has low operating temperature, low energy consumption, low phospholipid content, acid value and peroxide value of the extracted oil, light color and less pollution And other advantages, in line with the requirements of “safe, efficient and green”. With the application and promotion of microbial technology in enzyme production, industrialized mass production of enzymes has reduced the price of enzyme preparations.
Therefore, the application of ultrasound-assisted enzymatic extraction of vegetable oils has become a hot topic for domestic and foreign scholars, scientific research institutions, and universities and colleges. Such as domestic Yang Huiping, “High-pressure cooking, ultrasonic-assisted water enzymatic treatment of rice bran technology”, Shang Jun and other “Response surface method to optimize the ultrasonic-assisted protease hydrolysis conditions of Hepu pearl oyster meat” and other research topics; foreign Rosenthal and others use fiber Peptidase, hemicellulase, pectinase and protease act on soybeans to study the relationship between oil yield and protein yield; Bocekska et al. explored research topics such as water-enzymatic extraction of corn germ oil. At present, there is no relevant report on the research of ultrasonic-assisted enzymatic extraction of tea seed oil at home and abroad, so that the research on this subject has a certain degree of advancement and prospectiveness. With the approval of tea seed oil as a new resource food by the Ministry of Health, and the great favor and demand of Chinese people for functional foods, it is of great social significance to focus on the enzymatic extraction of high-quality tea seed oil. Tea seed resources and the potential economic market also make it of great practical significance and economic value to explore the enzymatic extraction of high-quality tea seed oil technology.