Abstract: Aroma compounds in Scottish Macallan single malt and Japanese Yamazaki single malt whisky of two ages each were analyzed by headspace solid phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME/GC-MS). The results showed that esters, acids, and alcohols were the most abundant volatile compounds in all whisky samples, accounting for over 90% of the total. Odor activity value (OAV) was calculated for 58 of the 243 volatile compounds identified. Phenylethyl acetate, acacia alcohol, and trans-nerolid alcohol in Scotch Macallan whisky had higher OAVs, contributing to obvious floral aroma, while Japanese Yamazaki whisky had an obvious fruity aroma, due to higher OAVs of ethyl isovalerate, ethyl 2-methylbutyrate, and 1-decanol. Two-dimensional hierarchical clustering analysis suggested that the typical aroma compounds in Yamazaki whisky were 2-methylbutyrate ethyl ester, butyrate ethyl ester, and isovalerate ethyl ester, while those in Macallan whisky were acacia alcohol, trans-nerolid alcohol, and damastone. Additionally, principal component analysis (PCA) confirmed that each whisky had unique aroma characteristics. This study suggests that flavor characteristics are an important index for the evaluation of different whisky samples.

Key words: single malt whisky; headspace-solid phase micro extraction-gas chromatography-mass spectrometry; aroma compounds; two-dimensional hierarchical clustering analysis; principal component analysis