Identification of red kernels
Barley malt intended for use in beer brewing or elsewhere in the food industry.
Visual evaluation
A relationship is suspected to exist between the metabolic by-products of Fusarium graminearum and Fusarium culmorum and the phenomenon of primary (malt-related) gushing. Furthermore, the upper limits for mycotoxins found in grain products have been established and are subject to regulations in Germany and the rest of Europe. Current limit values can be obtained from www.deutsches-bier.net or info@brauer-bund.de. Fusarium species form a red pigment which leads to noticeable red discoloration of contaminated malt kernels. However, other types of fungus, in addition to Fusarium species, are also able to produce red pigments. Therefore, a differentiation among the red kernels should be performed.
The moisture content of adjuncts is determined through the loss in mass during a standardized drying process, in which ground malt is dried at a defined temperature within a specified time in an electrically heated drying oven.
The moisture content is determined through the difference in the weight of the adjuncts prior to and after drying.
For samples with a moisture content greater than 17 % (for corn over 15 %), the sample has to be dried prior to conducting the analysis.
The sample is extracted with petroleum ether in a Soxhlet apparatus equipped with a reflux condenser; the solvent is evaporated and the crude fat residue weighed.
The β-glucan content of barley intended for use in beer production should be known.
After corn starch is converted through the addition of purified, heat-stable α-amylase during a 15 min boiling process and subsequent Congress mash procedure, the extract content is determined.
This method describes how to determine the extract content of liquid adjuncts by means of relative density measurement.
Adjuncts in liquid form which are soluble in water
Determination of relative density sL 20/20 °C with a pycnometer or other suitable density measurement device