Influence Of Hop Aroma Compounds On Beer Flavor Quality

The method of determining hop volatile components was established by HS-SPME/GC-MS.According to the research,The HS-SPME conditions for hop volatile components analysis were as follows:extraction temperature,time and sample weighing was 60℃,30 min and 2.0 g,respectively.Multivariate analysis—discriminant analysis was applied for result evaluation basing on analysis method above.The result indicated aroma hop and bitter hop can be distinguished according to category-center distribution of different hops.The method of determining linalool,citronellyl acetate,α-terpineol,geranyl acetate,β-citronellol,geraniol,trans- nerolidol were also established by HS-SPME/GC-MS.The recovery of linalool,citronellyl acetate,α-terpineol,β-citronellol,geraniol,trans-nerolidol was 86.4%,89.2%,128.6%,82.2%,93.5%and 70.4%,respectively.The detection limits between 0.005～0.024μg/L and correlation coefficient more than 0.9961.The content of linalool was regarded as important indicatrix estimating hop aroma in beer.The statistical analysis and sense organ evaluation of detected datas of hop aroma components in beer indicated there was significant deviation of hop aroma quality among brand,type and place of production.On base of two analysis methods above,The effects on hop aroma quality in beer were researched from hop variety and adding time of hop.The result indicated linalool can not be found in beer without adding hop and the content of it was different in beer with adding different aroma hops.Changing of adding hop time could effected on hop aroma of beer.Both the content of linalool and hop aroma of beer could be improved if adding the last hop into whirlpool tank with the same condition of hop adding amount.