| Camellia oil as a unique edible oil in China,is famous for nutritional value and health-care functions. With.the improvement of people's life, most of the consumers will inevitablely pay more and more attention to the tea oil that is good to health, therefore, the production of high quality camellia oil has become necessary.Different species of camellia and different methods of preparation for the camellia oil have certain impacts on the quality of camellia oil, therefore, a.good camellia species and appropriated methods of preparation for camellia oil can help to improve the quality of camellia oil. Camellia chekiangoleosa Hu.belongs to the genus Theaceae Camellia, and is a species with the double feature of ornamental gardens and its seed kernel can be extracted to edible oil. Generally, it is suitable for growing in warmming humid mountain areas with 600～1200 m altitude, mainly distributed in Zhejiang Province, and also in Fujian, Jiangxi, Hubei and Anhui. The growing area and the output of Camellia chekiangoleosa Hu.are in the nation's fourth of Camellia oleifera species. Its oil content and fatty acid composition are better than Camellia oleifera, and it is an excellent edible oil trees.The method of aqueous extraction of oil is accord with the demands of safety, nutrition and green,and it has less environmental pollution and low cost.The Camellia oleifera'shelling can be mechanized, and its oil content is high, and then,it is suitable for aqueous extraction to take the oil.In addition, a large number of studies have shown that Camellia oil aroma constituent and fatty acid constituent are closely linked to the oil quality. Thus, the study of aqueous of Camellia chekiangoleo-sa seed oil and understanding the mainly aroma constituent and fatty acid constituent have important significance for improving value of camellia oil and protecting health of consumers.In this thesis,the Camellia chekiangoleosa'oil is extracted from Camellia chekiangoleosa seeds by. the method of aqueous extraction according to the qualification of the demands of safety,nutrition and green. The quality analysis of Camellia chekiangoleosa oil is analyzed by organoleptic assessment, routine indicators,aroma and fatty acids components.There are four important indicators reflecting the quality of Camellia oil such as:①raw material of Camellia oil-economic traits of Camellia chekiangoleosa;②aroma of Camellia oil,③routine indicators,④components of fatty acids.The thesis is organized as follows:(1)The economic traits of Camellia chekiangoleosa were measured, according to the national standards.The results showed that the synthesis characters of Camellia chekiangoleosa seeds, i. e. TGWT, kernel rate,oil content,water content,are better than those of Camellia oleifera.(2)Firstly, slice the arid Camellia chekiangoleosa seed kernel, and rosted them at 170℃for 10min. After that, weight 10.00 g of the kernel accurately, and grinde them, and mixed the power with a certain percentage of water. Then, the stable temperature Horizontal shaking bath under different conditions (160 r/min) in some time were carried at 170℃for 10min and centrifuged at in the 4000 r/min for 10 min for extraction of the upper free oil, and obtain their weight. Eliminate the emulsion phase and water phase to get the slurry residue, and dried at 55℃for 12 hours, then measure residual rate. Single-factor experiment was designed and set the seed meal:water at 1:3(m:v),incubation temperature at 40℃, incubation at 90mins,and PH at 8 as the basic conditions. Then change one of the conditions and keep the other three conditions the same.With the highest oil extraction rate and free oil recovery as indicators, the optimum extraction procedure was obtained as follows:seed meal: water at 1:3 (m:v),incubation temperature at 60℃,and time at 120 min.The result is reliable by being tested at 3 parallel test verification. In experiment, the highest oil extraction rate and free oil recovery were up to 79.27% and 84.83% respectively.In addition,this study also found that the baking process,a part of pre-treatment of camellia seed,is not only impact on the oil extraction rate,but also the aroma of Camellia oil:the Camellia oil with the pre-treatment of baking before extraction have pure and characteristic aroma of Camellia oil and go with aroma of herb without baking.(3)The aroma of Camellia chekiangoleosa oil,which was obtained by aqueous etraction,was described by sensory evaluation, and according to the national standard,the conclusion from the test results are as follows:the Camellia chekiangoleosa oils is conform to the requirements of oil sensory of standard vegetable oil.Two indices, odor and transparency, were better than those of oil-tea camellia oil specified in GB-11765. the indices of odor and olfactory is excellent according to standard of.olfactory sensory on the odour of camellia oil.Quality index of Camellia oils were tested,and according to the national standard,the conclusion from the test results are as follows:except for the water and volatile content,the other indices of quality of aqueous extracted oil were better than those of oil-tea camellia oil specified in GB-11765. In addition, the result of the value of Saponification of.Camellia chekiangoleosa oils shows that the content of fatty acid of small molecular weight was higher than that of camellia oils.(4)Camellia chekiangoleosa oil which was obatained by aqueous extraction in laboratory as materials,the aroma of camellia oil was researched by Head Space Solid Phase Micro-extraction(HS-SPME)contecting with GC.The conditions of HS-SPME extracting the volatile profiles of camellia were optimized, and the analysis effect of GC was verified. Total peak area, ratio of total peak area to number of peaks, peak number and peak area of main volatiles were as evaluation indexes. The effect of stirring rapidity, extraction time, desorption temperature and time for extracting volatile profiles was studied. Extraction conditions were found that:1.00 g oil sample in 15 mL vessel, exposure for 25 min at 40℃, stirring at 100r/min, and desorption for 5 min at 260℃in GC.Calibration curves of 11 standards showed good linearity, with coefficients of determination(R2) ranging from 0.8543 to 0.9989 and limits of detection(LOD) from 0.14 ng/g to 79.78ng/g,the recoveries from 91.70% to 107.71% with an average 98.87%. In repeted experiments,RSD coefficient of variation in seven times successive standards determinations ranged from 2.46% to 4.84%. The results showed that the method has a good maneuverability.The eleven main aroma conponents of Camellia chekiangoleosa oil and Camellia oil were qualitative and quantitative analyzed by GC,and the eleven aroma standards are Ethyl acetate,4-methyl-2-pentanone, N-butanol, Hexanol, Benzaldehyde, Butyl acetate, Heptanol, Octanol, Octanal, Nonanal, Nonanol. The results showed that,The contents of eleven aroma components of two different Camellia oil are similar, but the specific contents are different.(5)By GC detection technology, the fatty acid composition of Camellia chekiangoleosa oil and Camellia oil were analysed. The fatty acid composition of Camellia chekiangoleosa oil is mainly the same as Camellia oil.The main chemical components is oleic acid and also have several difference as follows:①The oil oleic acid (C18:1), linoleic acid (C18:2), myristic acid (C14:0)and tetracosanoate acid (C24:0) in Camellia chekiangoleosa oil are higher in the relative content in the fatty acids.②Camellia chekiangoleosa oil can be detected a little arachidic acid (C20:0) and linolenic acid (C18:3), but normal tea oil can't detected them.③Compared with Camellia oil, Camellia chekiangoleosa oil oil is lower in palmitic acid (C16:0), stearic acid (C18:0), behenic acid (C22:0), Erucic acid (C22:1) in the fatty acids.④The total content of unsaturated fatty acids in Camellia chekiangoleosa oil is higher than in the camellia oil.⑤The total content of saturated fatty acids in Camellia chekiangoleosa oil is lower than in the camellia oil.By analysis of the fatty acid composition,the Camellia chekiangoleosa oil is better than camellia oil.The results are of great significance in the improvement of tea oil production technology,improving the quality of tea oil and meet the consumers demand of high-quality tea oil.
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