The Supercritical Carbon Dioxide Extraction and Functional Quality Evaluation of Camellia Seed Oil
|School||Changsha University of Science and Technology|
|Course||Of Food Science|
|Keywords||Camellia seed kernel oil The Supercritical CO2 extraction Alkali refining Lowering of blood lipid and protection of liver Function evaluation|
Camellia seed oil is a kind of high-grade edible oil which is unique in China and dominant in Hunan Province. It is well-known as the "oriental olive oil", because its fatty acid composition is similar to olive oil–"vegetable oil Queen" in the morden world. However, our traditional process of camellia seed for oil is mostly press?technology with high-temperature or solvent extraction technology, by which crude camellia seed oil was available with deep color, more impurities, and necessary to be completedly refined, resulting in much loss of nutritional content and natural bioactive substances in the oil; what’s more ,solvent extraction process requires use of certain toxic chemicals, which is harmful to the production environment and food security. Therefore, camellia seed oil produced by the traditional techniques actually falls short of the reputation of " Oriental olive oil". Today, people advocate natural food and food safety. It’s of great significance to carry out the ecological producing technology of camellia seed oil, to evaluate it’s safety and health functions, to protect the environment and oil safety and enhance the competitiveness of camellia seed oil products in the international trade.In this paper, camellia seed oil produced by supercritical CO2 extraction technology and its refining process were optimized. The advantages of the technology and liver lipid-lowering function of the camellia seed oil were comprehensively evaluated. Innovative conclusions as following:Using response surface method, we get the optimum process parameters of extraction of camellia seed oil by supercritical CO2 extraction technology. The result showed the yield was up to 96.5% at 33MPa and 43℃for 2h. Apart from the acid value of crude oil exceeds the criteria, other quality indicators can meet （GB11765-2003） the requirements of a specified level of camellia seed oil.The quality of the crude oil of camellia seed produced by supercritical CO2 extraction accorded with the requirements of the primary pressing camellia oil according to GB11765-2003, just after simple alkali refining processing. Through the orthogonal test,we concluded that major and minor factor affected alkali refining of were lye concentration > the initial temperature of alkali refining > super-alkali. The optimum conditions of alkali refining process wre alkali refining initial temperature 75℃, NaOH concentration of 8%, excess alkali of 0.10%. Under this optimum condition, recovery ratio of oil was 96.4%, acid value of the product was 0.10mgKOH / g, peroxide value was 2.48mmol/Kg.Comparing with the enzymatic extraction, expelling and solvent extraction methods of camellia seed oil, supercritical CO2 extraction of camellia seed oil has lots of comprehensive advantages, such as short extraction time, high extraction efficiency, light color of crude oil, more vitamin E and other bioactive ingredients in oil and more convenient to use meal by-products. However, its weakness is obvious, mainly in small-scale production equipment, a large one-time investment and so on.Animal test results showed that camellia seed oil can significantly reduce serum total cholesterol （TC）, triglyceride （TG） levels （p <0.05）, besides, plays a role of protecting against fatty liver and the atherosclerosis.