Effects of heat treatment on the profile of volatile flavor components in bamboo shoots

The effects of different heat treatment conditions (105, 110, and 120 degrees C; 10, 20, 30, 40, and 50 min) on the flavor profiles of bamboo shoots were investigated using headspace/solid-phase microextraction-gas chromatography/ mass spectrometry/olfactometry-odor activity value (HS/SPME-GC/MS/O-OAV) and sensory analysis. Results indicated noticeable differences in the amount and rate of changes in both original and newly produced flavor components in bamboo shoots at different temperatures. The retention rates of hexanal at 105 degrees C, 110 degrees C, and 120 degrees C were 8.55-34.41%, 7.28-34.32%, and 5.22-11.08%, respectively, whereas (E)-2-hexenal, (E, E)-2,4heptadienal, (E, Z)-2,6-nonadienal, 1-hexanol, 1-octen-3-ol and 2-pentylfuran were mostly lost after heat treatment. The content of three lipid oxidation compounds (octanal, nonanal, and decanal) increased 75.59-500.67%, while the content of newly generated Maillard reaction compounds (e.g. methional, furfural) increased (0-12.58 mu g/kg) with heating temperature and time. Sensory analysis indicated that the bamboo shoots heated at 110 degrees C for 30 min had the best overall flavor. These findings suggested that moderate heat treatment could eliminate some grassy and mushroom flavors from bamboo shoots, enhancing their sweet flavor. This improvement could be favorable for the consumer acceptance of heat -processed bamboo shoots.