| The cassia oil is that the leaf distillation of the cinnamon has, and the a little yellow or yellowish-brown bright and clean fluid, have strong fragrance. Apply spices and medicine to the food extensively, it is important raw materials which are made toilet soap and cosmetics. The fragrance composition adjusts an important ring in fragrant work, play an important role to the examining out of impurity in quality. It is at raw material planting in cassia oil, it produce,etc. the courses may last pesticide, pollutions of heavy metal, eat extensive concern of receiving people of safe problem as food additive it, so it is right to distinguish the true and false to study the oil fragrance composition of cassia oil and harmful substance, promote relevant standard formulation, it is healthy to guarantee the people and should be significant for technological barrier in foreign countries. The main result of study of this text is as follows:The fragrance composition of cassia oil were analyzed by GC-MS method combined with Headspace-solid-phase microextract. 41 peaks were identified by comparing their mass spectra with those contain in the NIST database using AMDIS and with some references.The aroma components could be classified into 4 groups,namely aldehydes,ketones,esters,alkenes. Among them,the contents of aldehydes and alkenes were 81%,10%,respectively.The relative content of the highest were trans-cinnamaldehyde(70.5%).Theywere principal contributors of cassia oil flavor.To establish a method for simultaneous determination of lead,arsenic and mercury in cassia oil by atomic fluorescence spectromety.Microwave-digestion technique using HNO3-H2O2 was applied for the pretreatment of samples.The instrumental operation parameters had been optimized. The experimental reaction systems were improved and conditions such as concentrations of KBH4,thiourea-as corbie acid and HC1 in the reaction medium were optimized,respectively.The influence from co-exist foreign ions and the elimination were also atudied.Under the optimized conditions,The detection limit of lead was 0.25ug/L, 0.068ug/L for aresenic and 0.012ug/L for mercury.The correlation coefficient was more than 0.995.The relative standard deviation were2.47%-4.95% in the range for lead, 2.65%-4.50% for arsenic and 2.47%-4.95% for mercury.The spiked recoveries were 86.5%-94.3% for lead, 83.2%-90.0% for arsenic and 86.5%-94.3% for mercury.The method is simple,rapid,accurate and sensitive.It canbe adopted for simultaneous determination of lead,arsenic and mercury in cassia oil.The 13 pesticides in cassia oil can be rapidly extracted and separated by gel permeation chromatography,and the lipin and pesticide of cassia oil can be seperated.The interfering matters can be well eliminated in this condition,and analysis was more rapid than other methods.The residues of 13 pesticides at same time can be identified and quantified simultaneously by GC-MS.The average recovery ratios were 80.9-100.7%.Good repeatability was obtained in all the cases with coefficients of variation lower 14.7%,and limit of detection was 1.2-9.2ug/kg. |
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