Syudy Of The Method For Determination Of Adulteration In Camellia Oil

Recently, food safety has become a major concern in our country. Among them, edible vegetable oil accidents, including adulterating low-level oils, are frequently occurred. In order to protect the rights and ensure the health of consumers, the establishment of reliable methods for quality control of edible vegetable oils is very desirable. In this thesis, the methods for the determination of adulterations in camellia oil were established based on the GC-MS analysis and the main contents are as follows:1. The fatty acids both in camellia oil and five low-level vegetable oils including soybean oil, peanut oil, rape oil, cotton oil and palm oil were determined by GC-MS method after derivatizing with methanol. It was found that that the contents of fatty acids in these oils exhibited obvious differences. And then, a quantitative method for determination of above five low-level vegetable oils adulterated in camellia oil was established by the analysis of selected specific fatty acids. The recoveries of the method were between84.4-116%and the correlation coefficients of the linear regression equations were more than0.99.2. By static headspace technology combined with GC-MS analysis, a large number of volatile compounds both in camellia oil and five low-level vegetable oils including corn oil, soybean oil, peanut oil, rape oil and cotton oil were isolated and detected. These volatile compounds are determined to aldehydes, alcohols, organic acids and others. By comparing the compounds from different kinds of oils, it was found that there normally contained two specific compounds,3-dodecyl-dihydro-2,5-furandione and8-undecanoic acid lactone, among the volatiles of above five low-level vegetable oils. But these two compounds were not found in the volatiles of camellia oil. Thus,3-dodecyldihydro-2,5-furandione was selected as identified compound and a quantitative method for the determination of above five low-level vegetable oils adulterated in camellia oil was established with RSD less than5%.3. By SPME technology combined with GC-MS analysis, more than50volatile compounds in camellia oil were isolated and determined. It was found that there contained an identified compound Z, E-2,13-octadecadien-1-ol in the volatiles of camellia oil, and the concentration of this compound was linearly decreased after adulterating with four low-level vegetable oils such as rape oil, soybean oil, cotton oil or corn oil. Thus, a quantitative method for the determination of these four oils adulterated in camellia oil was established with correlation coefficients more than0.99. It was also found that the concentrations of Z, E-2,13-octadecadien-1-ol in refined and crude camellia oil are different.The above methods are efficient and practical in the determination of single adulterations in camellia oil. They could be applied to the quantity control of camellia oil. However, the simultaneous quantitative deter-mination of more than one adulteration in camellia oil is still challenged.