Using the volatile fingerprint for exploring differences among hops varieties.

During the past centuries, Adding flavor and bitterness to beer got attention of brewers to Hop (Humulus lupulus L.).Exploring special characteristics and qualitative aspect of hops can be lead to superior products. Chromatographic profiling or fingerprint of volatile compound is employed to characterizing different hops varieties and qualities. In this study we performed volatile finger printing by using solid phase Microextraction (SPME) Gas chromatography- Mass spectrometry (GC-MS)Combined with Cluster analysis(CA) and Principal Component Analysis(PCA) for assessment and differentiation between fifteen varieties of hops cultivated in the Marche region. Sixty one volatiles were identified which were classified into seven categories .The CA showed three clusters and the main percentage of aroma profile in all cluster ( from 84.3 to 93.1) belong to the Terpene Hydrocarbons.β-myrcene , β-caryophillene as well as α-caryophillene are the most abundant components in all varieties. More over the PCA identified that three Principal Component (PC) can explain 90% of total variance of all hops varieties.in conclusion volatile fingerprint plus multivariate statistical analysis can differentiate between different varieties and qualities of hops .In addition GC-MS not only can able us to classified hops to Aroma hops, Bitter hops and dual purpose hops but also inform us to choose fitting varieties for desirable beers .