Hops and hop products are subject to aging processes which depend upon the conditions during storage and in the surrounding environment. In order to assess the freshness of hop products, analytical methods capable of detecting aging compounds are necessary. However, since the existing methods record changes in the spectrum of the constituents in hops, they are only applicable to conventional products. The closer a product is in chemical composition to hop cones, the more relevant the applied evaluation criteria are.
The transformation of bitter substances into iso-α-acids is only desirable in isomerized products. Therefore, it is not appropriate to evaluate this kind of product by the presence of isomerized compounds in it.
This method describes how to determine the hard resin fraction in hops and hop products; for the procedure, refer to the MEBAK method R-300.03.901 [2016-03].
Hops and hop products intended for use in beer brewing or elsewhere in the food industry
The hard resins are calculated by subtracting the soft resins from the total resins. This yields the hard resin content as a percentage of the total resins.