Study On The Application Of Solid Phase Microextraction Combined With GC/MS In Volatile Constituents Analysis Of Some Vegetable

Flavor is a critical factor of foodstuff quality. Nowadays the researchers studied the foodtuff flavor mechanism is the mostly focused on some chemical components producing smell. And also these chemical components were easily determined and evaluated using some modern techniques. The instruments for analyzing foodstuff flavor mainly included GC, HPLC, GC-MS, HPLC-MS, HPCE etc. For preparing samples, some advanced techniques and method are used such as supercritical extraction , solid phase microextraction etc.Solid phase microextraction (SPME), gas chromatogram (GC), combined with mass spectrum (MS) were applied to analyze the volatile constituents of vegetable. Many factors that affected the extraction were discussed, such as SPME fiber , chromatographic column, extraction temperature, extraction time, desorption time, electrolyte. The optimum SPME method in analysis of volatile constituents of vegetable was found by analyzed celery.The results shows that , the optimum extraction condition of SPME-GC is the OV-1701 chromatographic column, 75μm CAR/PDMS extraction fiber, the extraction temperature of 50℃, the extraction time of 40min, the desorption time of 7min, and adding NaCl in sample.The optimized SPME method combined with GC/MS was applied to analyze the volatile constituents of celery, coriander, lettuce, tomato, vegetable marrow, chinese wax gourd, bitter melon and cucumber in Gansu province.The results shows that aldehyde, alkene and alcohol are the major volatile constituents of vegetable.79 volatile compounds were identified in celery ,in which alkene relative content was 72.15% of the total peak area. 79 were identified in coriander, 49 in lettuce, 83 in tomato, 66 in chinese wax gourd, 87 in cucumber. The major volatile constituents is aldehyde in above, which was aldehyde and alcohol in bitter melon . 83 volatile compounds were identified in bitter melon, 63 in vegetable marrow. The major volatile constituents in vegetable marrow was alcohol, its relative content was 45.40%.