Analysis of Monoterpenol Isomers in Hops and Beers: Comparison of Methods with a Chiral Column and a Nonchiral Column

​The aim of this work was to develop a novel method using a chiral column to determine the terpene alcohol isomers in hops and beer. An optimum procedure was designed, and the storage variation within one month was tested. The results of the sum of isomers by this new method and unseparated isomers by a method with a nonchiral column were compared. The statistical comparison results demonstrated the validity of the novel method employing a chiral column. This method was applied to the analysis of 18 varieties of hops and 14 brands of beer. The results showed that R-(–)-linalool was the primary linalool enantiomer in the hops but not in the beers. R-(+)-β-citronellol, S-(–)-β-citronellol, citronellyl acetate, (–)-α-terpineol, and (+)-α-terpineol were detected in the beers but not in the hops. Furthermore, R-(+)-β-citronellol and (+)-α-terpineol were the major isomeric forms in the beers owing to their respective biosyntheses. Keywords: Chiral separation, Terpene alcohols, Enantiomeric distribution, Hop aroma, (R)-(–)-Linalool, Solid phase microextraction, S-(+)-Linalool