Applied Study On Discrimination Of Adulterated Camellia Seed Oil With Capillary Gas Chromatography

The fatty acid methyl ester from common vegetable seeds was directly used in the study, without using standard sample of methyl ester., emphasis discussion on the influence of chromatographic separation,peak height,peak area and retention time base on setting condition of GC, found an optimized chromatographic parameters: oven temperature: temperature-programed condition was 180℃12℃230℃(1min) 8℃250℃(2min), the measurement procedure of GC take 10 minutes per sample; carrier gas flow rate:1mL/min; detector temperature:260℃; injector temperature:260℃; split injection ;H₂ flow: 40mL/min; Air flow: 400 mL/min; make-up flow rate 40 mL/min. ECL values measurement in this thesis compared with standard values in documents showing difference awfully little, so the experiment operation system is steady and reliable. the measured results of a few species main edible oil closely matched the national standards. This method has simplified the extraction process of alkaline catalyst with methyl ester by combining the independent processes of fatty acid methyl esters extraction and esters exchange into one step. The method is simple, rapid, and accurate, which can be used to measure fatty acid compositions of vegetable oil with large samples. Using this method under the best experimentation conditions, the fatty acid compositions were measured in the study for pure camellia seed oil and those camellia seed oil with different degrees of adulteration. The data were used to calculate the adulteration for each sample with the standard curve method in order to derive the percentage of adulterated oil. The error analysis was conducted in order to provide evidence for selecting the actual composition of the fatty acids.At last, the weighted vector angle method was used in the study to measure the similarity of fatty acid compositions between the pure and adulterated camellia seed oil in order to obtain the respective weighted similarity, including fitting curves of adulteration relations and the regression formula of quantitative measurements.