基于全自动顶空固相微萃取箭型-气相色谱-质谱法分析老面小米馒头发酵过程中挥发性成分

Analysis of Volatile Components of Sourdough Foxtail Millet Steamed Bread During Fermentation Based on Gas Chromatography-Tandem Mass Spectrometry-Headspace-Solid-Phase Microextraction Arrow

为更好地萃取老面小米馒头的风味物质,文章对固相微萃取(Solid-phase microextraction,SPME)箭型(Arrow)不同萃取图层进行筛选,并优化了萃取条件,并结合气相色谱串联质谱法(Gas chromatography-tandem mass spectrometry,GC-MS)比较Arrow法和传统SPME法的萃取效果差异。结果表明,最佳萃取条件为:Carbon WR/PDMS萃取图层、加水量0 mL、萃取温度60℃、萃取时间30 min;Arrow法相比较传统SPME法所得到挥发性风味物质种类更多且浓度更高。利用Arrow法测定不同发酵时间(2、4、6、8、10 h)老面小米馒头的风味物质,分析发现发酵4 h馒头的挥发性成分最丰富,共鉴定出39种化合物;其中,一些主要风味化合物如苯甲醛、辛酸乙酯、异戊醇、壬醛等对构成其特征风味具有重要作用。

In order to better extract the flavor substances of sourdough foxtail millet steamed bread,different extraction layers were selected and extraction conditions were optimized.The extraction effects of solid-phase microextraction(SPME)Arrow and conventional SPME combined gas chromatography-mass spectrometry(GC-MS)were compared.The results showed that the optimum extraction conditions were as follows:Carbon WR/PDMS extraction layer,0 mL water volume,extraction temperature of 60℃,and extraction time of 30 min.SPME Arrow outperformed conventional SPME by identifying a larger number of flavor compounds with higher concentrations.Moreover,the flavor substances of sourdough foxtail millet steamed bread at different fermentation times(2,4,6,8,10 h)were determined using SPME Arrow.It was found that the volatile components(39)of the 4 h fermented steamed bread were the most abundant,with some key flavor compounds such as benzaldehyde,ethyl caprylate,isoamylol,and nonanal playing important roles in constituting their characteristic flavors.