The Influence of Milling Granulation on The Proportion of Fermentable and Non-Fermentable Ingredients in Mash Obtained from Mixed Endosperm Wheat

Abstract

The use of purpose-selected wheat in brewing is limited because it is either not suitable for the application of usual agrotechnical measures or, more often, is not adapted to specific climatic conditions. As unmalted wheat in brewing can cause process problems and problems with the quality composition of mash/wort and consequently beer, by using the appropriate type and variety, but also by adjusting the malting process, these problems can be completely avoided or significantly reduced at the start. Two varieties were selected for the research, which in previous research showed good brewing/malting properties and which have significantly different starting values for the share of total protein (TP) in the grain. The goal of this research was to determine the effect of grain milling granulation on the quality of mash obtained from a hard type of wheat, i.e., the changes in the fermentable and non-fermentable extract ratio during mashing. Varieties with higher and lower initial contents of total protein (TP) in the grain were tested. It was found that regardless of the initial difference in TP concentration, the concentrations of total soluble proteins (TSP) and high molecular protein fraction (HMW N) are similar for varieties with higher and lower initial TP and that the difference in initial TP concentrations is shown as a difference in the concentration of insoluble protein fractions, which are eliminated during fermentation. By increasing the milling granulation in both kinds of wheat, there is a significant increase in the medium molecular protein fraction (MMW N), which is more pronounced in wheat with a lower starting concentration of TP, even though the starting concentrations of TSP in fine (Ø 0.2 mm) and the superfine milling (Ø < 0.2 mm) were similar. A significant drop in fermentability at the superfine granulation of the grain was noted.