Barley intended for the production of malt is evaluated with regard to pre-germination.
Visible pre-germination is evident at the rootlet and is therefore grounds for rejecting a barley lot. However, after the barley is cleaned and the rootlets are removed, the so-called “hidden pre-germination” can be made visible using the staining methods described below.
Kernels suspected of having pre-germinated are boiled for ½−1 min in a 20 % solution of copper sulfate, allowed to remain for 30 min in the hot solution and are subsequently rinsed with water. The acrospire is stained green, making it clearly visible.
This method describes how to determine whether malt is (once again) capable of germination.
Malt intended for use in beer brewing or elsewhere in the food industry.
In living kernels, in the presence of oxidoreductases and their corresponding coenzymes, the colorless compound triphenyl-tetrazolium chloride is reduced to formazan, which is red in color [1].
or
Under the influence of oxygen, barley kernels emerge from dormancy. In this way, germination can be induced at any given time.