Study On Lipid Composition And Variation Of Oil Camellia Oil And Aqueous Enzymatic Extraction

Oil Camellia is a popular oil-bearing plant in China. It is mainly distributed in the Yangtze River and the South China. At present, the planting area of Camellia plant is more than 60 million, and camellia seed oil production is approximately 250 million kilograms. Oil Camellia seed oil is one of a traditional edible vegetable oil in Southern china. Oil camellia seed oil contains about 80% oleic acid, and it is healthful to human. The industry of woody oil-bearing plant is get more and more attention in china, but few of reseach foucused on the lipids compositon and variation of oil camellia seed oil from the level of species, varieties and different growth stage. In this paper, we analyzed the content and compositon of fatty acids, triacylglycerols, volatile, nutrients of oil camellia seed oil for different camellia species and varieties, and we also study the variation of these components in oil camellia seed oil at different growth stages. We optimized the method of aqueous enzymtic extraction to obtained higher oil recovery, and compared the physicochemical properties and content of nutrients of oils extraced by different methods.1. The oil content, physicochemical properties of oil, fatty acid composition and nutrients content were analyzed from 6 speces of oil camellia and 12 varieties of Camellia Oleifera Abel. It was found that there were significant differences (p<0.05) of oil content for different species and different varieties, but no significant correlation was found between oil content and fatty acid content. the negative correlatin was found between the content of oleic acid and palmitic acid, linoleic acid, linolenic acid in camellia seed oil; there were significant differences (p<0.05) between nutrients (sterols, vitamin E, squalene) content of different species and varieties, but there was no no correlation between oil content and nutrients content, which indicates it would breed the varieties with high oil content and high nutrient content in theroy. Principal component analysis was utilized to develop a a comprehensive evaluation system to evaluate different oil camellia species and varieties on the basis of content of oil and nutrients. The volatile substances include esters, carbonyl, acids, alcohols, alkenes, alkanes in oil camellia seed oil.2. It was found that oil contentnt is rising throughout the maturation of camellia seed (Camellia Oleifera Abel.) and total soluble sugar, soluble protein first increase and then decrease. In the maturation process of 4 varieties, total saturated fatty acid content decreased, but unsaturated fatty acids content increased at the same time, especially oleic acid increased rapidly. In camellia seed maturation process, α-tocopherol, P-sitosterol, squalene showed down trends, α-tocopherol and β-sitosterol content was first decreased and then slightly increased. The volatile profile of our different oil camellia varieties includes esters, alcohols, carbonyls, alkenes, alkanes. With the maturity of oil camellia seed, their trends were basically the same, the content of esters was first up and then down, carbonyl and alkanes content was slightly fluctuations. Cinnamate is present throughout the growth, and its content firstly went up and then decreased.3. The profile and content of triglycerides was studied from the level species, varieties and stages of growth of oil camellia. There were 24 types of triglycerides in oil. it mainly contains trioleate triglyceride (OOO), dioleate one linoleic acid triglyceride (OOL) palmitic acid and two oleic acid riglyceride (OOP), one palmitic acid one oleic acid, linoleic acid riglyceride (PLO) and an oleic acid, two linoleic acid riglyceride (OLL).4. An aqueous enzymatic extraction method was developed to extract oil from camellia seed. The combination of protease/cellulase yielded significantly more oil than did other combinations. Under the optimal reaction conditions, a free oil yield of 82.37% was obtained. Four types of demulsification methods were compared. After demulsification with 20% ethanol (V/V), the highest total free oil yield of 91.38% was achieved. Effects of different extraction methods on the physicochemical properties, fatty acid composition, bioactive compounds content of camellia seed oil were investigated. The expeller pressed-oil had the highest acid and peroxide levels of all of the oils. The aqueous enzymatic-extracted oil had a higher content of oleic acid, total monounsaturated fatty acids, a-tocopherol, β-carotene, squalene and phytosterol than hexane-extracted and expeller-pressed oils. Nine phenolic acids were detected, and 3-hydroxytyrosol, benzoic acid, catechins,4-hydroxybenzoic acid and chlorogenic acid were the predominant compounds. The content of phenolic compounds in the aqueous enzymatic-extracted camellia seed oil was lower than that of other oils. The phospholipid content of the aqueous enzymatic-extracted camellia seed oil and the supercritical fluid-extracted oil was significantly lower than that of the oils extracted using the other methods.