The effect of(E)-2-heptenal on Maillard reaction products was investigated by thermal reaction systems consisting of L-cysteine and D-xylose.The Maillard reaction products derived from the(E)-2-heptenal-containing model systems showed the increase in absorbance at 294 nm and 420 nm,suggesting that more intermediates and browning products produced in the reaction systems.The volatiles generated in different reaction mixtures were analyzed by solid-phase microextraction(SPME) coupled with gas chromatography-mass spectrometry(GC-MS).The results showed that the addition of(E)-2-heptenal had a suppressing effect on most of nitrogen-and sulfur-containing compounds derived from the reaction between cysteine and xylose,especially for 2-methyl-3-furanthiol,2-furfurylthiol,3-methylthiophene and 2,5-thiophenedicarboxaldehyde.However,some new alkyl-thiophenes were formed with a concomitant increasing content of(E)-2-heptenal,including 2-hexyl-thiophene,2-(1,1-dimethylethyl)-thiophene and 5-methyl-2-thiophenecarboxaldehyde.Compared with the control,new alcohols,ketones and esters were formed in(E)-2-heptenal-containing reaction system.