Identification of aroma-active components from cultivated agarwood ‘Qi-Nan’ based on GC-O-MS combined with aroma extract dilution analysis

Agarwood ‘Qi-Nan’ is commonly regarded as the highest quality agarwood, and has been highly valued for its fragrance. With the increasing amount of cultivated agarwood ‘Qi-Nan’ in recent years, evaluation of the aroma compounds was drawn attention. Therefore, the volatile compounds in three cultivated ‘Qi-Nan’ agarwood samples were extracted by simultaneous distillation-extraction (SDE) and analysed by GC-O-MS, combined with aroma extract dilution analysis (AEDA). A total of 70 volatile compounds were identified from three samples, in which sesquiterpenes and aromatics were characterized as key aroma-active components. Nine compounds were considered as common aroma-active volatiles in these three essential oils according to their flavour dilution (FD) activity and relative flavour activity (RFA) value, and among them, dihydro-β-agarofuran and 4-methoxy-benzaldehyde were the most important aroma-active compounds. Additionally, three ‘Qi-Nan’ agarwood samples showed different aroma specificity. TD agarwood was characterized by sweet sandalwood odour due to the dominant aroma-active compound of β-Santalol. WS agarwood was distinguished by its woody odour because α-kessyl acetate was its primary aroma. HQ agarwood was featured by woody, spicy and balsamic odour on account of its main aroma compounds of agarospirol and β-elemene.