Determination of Volatile Constituents in Daqu Using Headspace Solid-phase Microextraction and Gas Chromatography-Mass Spectrometry

The characteristics of volatile constituents of Daqu are determined by using headspace solid-phase microextraction and gas chromatography-mass spectrometry(HS-SPME/GC-MS).In order to optimize the extraction efficiency,the effects of SPME fiber,extraction temperature,extraction time,amount of sample and extraction mode are investigated by comparing the numbers and the area of peaks.The results show that the optimum extraction conditions are: CAR/PDMS SPME fiber of 85 μm,amount of Daqu is 2.0 g,extraction temperature of 60 ℃,extraction time of 50 min,and without solvent addition.Under the optimal extraction conditions,a total of thirty-four kinds of volatile constituents including two olefins,ten pyrazines,ten aromatics,twelve esters are detected and the amount of each constituent accounts for 5.88 %,29.41 %,29.41 % and 35.29 % of the total contents respectively.