Study On The Flavor Components And Odor Characteristics Of Foxtail Millet

Foxtail millet that has unique odor characteristic is a traditional crop in our country.In this paper,foxtail millet as the research object,the volatile flavor components and characteristic aroma components were analyzed,and through the identification of volatile flavor components of the foxtail millets which came from different habitats and different ecological areas,and adopting principal component analysis to evaluate the similarities and differences among the varieties of the foxtail millets.The results are as follows:By comparing with the three methods of solid-phase microextraction(SPME),simultaneous distillation extraction(SDE),and solvent extraction(SE)to compare the three methods,using gas chromatography-mass spectrometer(GC-MS)to separate and test the flavor components of the foxtail millet,and then determined that SDE technology was used to separate and collect the flavor components of the foxtail millet.The two methods of GC-O-MS and OAV were used to analyze and identify the odor active compounds which give the characteristic aroma of the foxtail millet,comparing and analyzing with the results of the key aroma which was identified by the two methods,the8 kinds of materials of hexanal,octanal,(E)-2-nonenal,(E,E)-2,4-nonadienal,(E,E)-2,4-decadienal,1-octen-3-ol,O-xylene and 2-pentyl-furan were the key aroma components of the foxtail millet which were simultaneously identified by the two methods.The characteristic aroma materials were preliminarily determined.The foxtail millet No18 of high yield and wide adaptability that came from Henan was chosen for material,the volatile components were extracted by SDE,the volatile components were identified by GC-MS,the key odor components were determined by OAV.The analysis results of principal components showed that 59 kinds of volatile components such as aldehydes,alcohols,ketones,benzene derivatives,hydrocarbons,heterocycles,phenols and acids,etc.which are contained in the foxtail millets of the different origins were detected,(E,E)-2,4-decadienal contributed the most to the odor,nonanal,(E)-2-nonenal,(E,E)-2,4-nonadienal also had great contribution to the flavor.Principal components were analyzed and obtained that the accumulative contribution rate of the 4 principal components was 94.46%.The volatile compounds of the foxtail millets that came from 13 commercial varieties were extracted by SDE and indentified by GC-MS,52 volatile compounds were obtained,including 19 kinds of aldehydes,5 kinds of alcohols,10 kinds of ketones,9 kinds of hydrocarbons,6 kinds of benzene derivatives and 3 others.Found that the 23 components are common to all samples.Different foxtail millet varieties usually have similar volatile compounds,but they exist at different concentrations.According to the value of OAV,it was found that the 24 volatile compounds were the odor active substances.11 of them were found in all samples.Principal components were analyzed and obtained that the accumulative contribution rate of the 6 principal components was 88.21%.