Release of volatile compounds from microwave heating of garlic juice with 2,4-decadienals

Garlic (Allium sativum L.) juice and 2,4-decadienals were heated in a microwave oven at the full power of 700 W. The volatile compounds of heated samples were isolated using diethyl ether solvent extraction and analysed using gas chromatography and gas chromatography–mass spectrometry. A total of 23 compounds were identified from these samples, among which 14 sulfide compounds, five aldehydes, two alcohols, one acid and one furan were identified. Three tentatively identified compounds, dithio(1-propenyl)propionate, dihydro-2(3H)-thiophenthione and n-hexanethiol were newly found in deep-fried garlic flavor. During microwave heating, levels of most volatiles decreased as the heating time continued. 2-Pentylfuran, isopropyl alcohol, hexanal and (E)-2-octenal were formed from the degradation of 2,4-decadienals. Sulfur dioxide was generated predominantly from the degradation and oxidation of sulfide compounds.