Table of Contents
An approach to develop an external dry hopping method by restoring the aroma transfer through dilution
M. Kohles, F. Gutsch, M. Zarnkow, F. Jacob, R. Novy and C. Schönberger
This work encompassed testing the impact of high mass concentrations of substances on the transfer of aroma and bitter compounds during dry hopping. For this purpose, a novel dynamic process for the production of cold-hopped beers was implemented on a laboratory scale. In this process, a suspension of hops and beer with a high concentration of 6.5 % w/w hops is prepared and diluted to 1.5 % w/w with beer. Then, the particulate matter is immediately separated from the beer using a filter. Evaluation of the bitter compounds, terpenes, esters and thiols using analytical methods indicated that the transfer of these compounds during dry hopping occurred similarly in samples which were hopped at the higher rate and subsequently diluted compared with those hopped at 1.5 % w/w but were not diluted. In sensory trials conducted by a panel of trained tasters (n = 10), no significant difference up to a significance of α = 0.20 could be detected by means of discriminative testing. Furthermore, no significant difference (α = 0.05) was found between the attributes of the beers in descriptive testing.
Descriptors: aroma transfer, dry hopping, dilution, extraction, hop oil, beer
BrewingScience, 74 (November/December 2021), pp. 151-159
