LAUSR

A potent unpleasant aroma presenting a pickle-like off-odor in Moutai-aroma type Baijiu was studied by comparative aroma extract dilution analysis (cAEDA). Two Moutai-aroma type Baijiu samples, one having no off-odor (A) and the other one presenting pickle-like off-odor (B), were selected for chemical analysis and sensory evaluation. The aroma compounds were isolated by headspace solid-phase microextraction (HS-SPME) and liquid-liquid extraction (LLE). AEDA, quantitative analysis, and odor activity values calculation (OAVs) were determined in both the A and B samples. Main differences between the two samples were obtained for 12 compounds presenting significantly higher concentrations in the off-odor sample. A total of 30 Moutai-aroma type Baijiu samples having different intensities of pickle-like sensory defect were analyzed to confirm the differences. An aroma addition test indicated that the 12 compounds with higher concentrations contributed to the pickle-like off-odor when spiked into sample A. Finally, a triangle test involving omission of the aroma compounds from spiked A proved that 2-methyl-3-furanthiol, methional, methyl 2-methyl-3-furyl disulfide, dimethyl trisulfide, 2-furfurylthiol, methanethiol, dimethyl disulfide, and bis (2-methyl-3-furyl) disulfide with higher concentrations were generally responsible for the pickle-like off-odor in Moutai-aroma type Baijiu.