ASBC Methods of Analysis - Hops-8: Hop Extracts
ASBC Methods of Analysis
Introduction of concentrated liquid extracts of hops into brewing as a source of bittering substances requires analytical procedures adapted to such materials. The basic principles for evaluation are the same as those elaborated in Hops-6 and Hops-7, but provisions are required for reextraction of bittering substances from the concentrates. The organic solvent used for such partitioning is selected on the basis of efficiency, adaptability, and compatibility with safety requirements in laboratory use. A major distinction in method development depends on whether the extract is non-isomerized (Hops-8) or isomerized (Hops-9). Further, a “reduced” extract may be produced, e.g., one containing p-iso-α-acids. This method discusses analysis of hop extracts by isopropyl ether spectrophotometric and conductometric methods.