Determination of fusel oil content in various types of liquor distributed in Korea

This study was performed to analyze the content of 6 different fusel oils in 9 types of liquor distributed in domestic market. GC-FID method was employed for quantifying fusel oil (1-propanol, iso-butanol, 1-butanol, 2-butanol, iso-amyl alcohol, active amyl alcohol) levels in 260 liquor samples of liquor. Relative standard deviations (%) of intra-and interday measurements were under 1.56 and 2.44%, respectively, while recovery rates (%) were 98.22-105.26% and 98.53-107.15%, respectively. Pretreatment method (filtering and centrifugation) of Takju did not affect analytic results. The average of total fusel oil contents in Yakju (39 types) and fruit wines (30 types) were 497.6 and 151.9 mg/L, showing Yakju contains more fusel oils than Takju or fruit wines. In fruit wines, iso-amyl alcohol was the major fusel oil component (at 6.8-249.0 mg/L). The highest content of fusel oil was found in foreign brandy, whereas the diluted Soju did not contain fusel oils. However, the average of total fusel oil contents was high at 764.5 mg/L in the three types of distilled Soju and iso-amyl alcohol content ranged from 114.2 to 421.0 mg/L. Domestic and foreign beers were similar in terms of their fusel oil compositions and contents. In conclusion, excluding the diluted Soju, the contents of total fusel oils ranged from 114.8 to 1447.3 mg/L in the monitored liquors.