Germinative capacity
Germinative capacity is the most important characteristic of malting barley. It measures the percentage of viable kernels in a barley sample, independent of whether they are still dormant or not.
The method provides an estimate of the portion of pre-germinated barley grains at the time of harvest or prior to storage in silos.
Barley intended for the production of malt is evaluated with regard to pre-germination.
The onset of germination is accompanied by the synthesis of enzymes, which can be made visible using fluorescein dibutyrate (FDB). The reagent fluoresces in the presence of lipases.
In order to make the enzyme activity visible, the kernels are first split in half and coated with the FDB reagent after which they are examined in a suitable measuring device under UV light. An intense yellow fluorescence can be seen in the parts of the kernels where enzyme activity is present.