This method describes how to determine the capacity for water imbibition (moisture uptake) in barley.
Barley intended for the production of malt is evaluated on the basis of its capacity for water imbibition.
Barley is steeped according to a defined scheme, and the absorption of the steeping liquor by the kernels at defined times is determined by calculating the moisture content. The moisture content after 72 h steeping time is used to assess the absorption of steeping liquor or the capacity for water imbibition in barley.
Potassium permanganate oxidizes many organic and certain inorganic substances more or less completely in acidic, neutral or alkaline solutions. The volume of potassium permanganate required in the analysis is determined potentiometrically. Since oxidation depends on the type of solution, on its temperature and on the reaction time, the procedure described below must be followed precisely.
In acidic solutions, permanganate ions are typically reduced to manganese(II) ions:
MnO4- + 5 e- + 8 H3O+ → Mn2+ + 12 H2O
In alkaline solutions, the reduction results in tetravalent manganese only:
MnO4- + 3 e- + 4 H3O+ → MnO2 + 6 H2O
Since in both cases the titration takes place in an acidic solution, this is irrelevant for the calculation. By adding oxalic acid, both the excess permanganate ions as well as the tetravalent manganese are reduced to manganese(II) ions:
2 MnO4- + 5 C2O42- + 16 H3O+ → 2 Mn2+ + 24 H2O + 10 CO2
MnO2 + C2O42- + 4 H3O+ → Mn2+ + 6 H2O + 2 CO2
This method describes the method for determining the germinative energy of barley by inducing germination in a germination box under defined conditions.
Barley intended for the production of malt is evaluated on the basis of germinative energy.
This method requires that the germination of barley be induced at a defined temperature and humidity. The germination period is three or five days.
Barley intended for the production of malt is evaluated on the basis of germinative energy.
Two analyses are carried out on 100 kernels each, in 4 ml and 8 ml of water.
Barley intended for the production of malt is evaluated on the basis of germinative capacity.
This method is used to determine the percentage of germination that will occur under normal malting conditions. The germination index provides a good indication of the germination capacity of a barley lot which is no longer dormant [1−3].
The method is based on the BRF/4 ml test with 4 × 100 kernels.
This method describes the determination of water sensitivity in barley.
Barley intended for the production of malt is evaluated on the basis of water sensitivity.
The 4 ml test measures the normal germinative energy of a barley sample. The 8 ml test provides information regarding the level of water sensitivity. During the steeping process, the water sensitivity of a barley sample must be taken into consideration. The duration of the air rest or dry-steep period must be extended with increasing sensitivity.
The water sensitivity is expressed as the difference between the germinative energy measured in the 4 ml and 8 ml tests.