1,1-Diethoxymethane and methanethiol as age markers in Chinese roasted-sesame-like aroma and flavour type liquor

摘要

Roasted-sesame-like aroma and flavour type liquor is extensively welcomed by consumers owing to its typical aroma, particularly in the north of China. To our knowledge, age markers which can distinguish between fresh and aged raw liquor have not been investigated. 1,1-Diethoxymethane and methanethiol were identified and quantified by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. The results showed that 1,1-diethoxymethane was not detected in all fresh raw liquors, and the contents increased with raw liquor age, contrary to the great decrease of methanethiol. Both of them showed good correlations with raw liquor age (R-2 = 0.955 and R-2 = 0.695, respectively). Furthermore, the reduction in the concentrations of methanethiol and derivatives (rotten cabbage aroma) might be responsible for the mild aromas of aged raw liquors. Therefore, our research suggested that 1,1-diethoxymethane and methanethiol could be used as effective age markers of roasted-sesame-like aroma and flavour type raw liquor.