Making the Cut: Options for Making Initial Evaluations of Malting Quality in Barley

Abstract

Alternatives to traditional methods of estimating the potential malting quality of barley lines were examined through their application to two regional barley nurseries, with the goal of identifying streamlined procedures suitable for making initial assessments of malting quality. Mashing malt using an isothermal hot water extract (HWE) procedure instead of the standard Congress mash generated distinct but closely related values for primary measures of malt modification, including malt extract, wort soluble protein, soluble/total malt protein, wort β-glucan, and wort free amino nitrogen. Simple measurements of other wort properties, including refractive index and wort osmolyte concentration, also showed strong correlations between Congress and HWE worts. Analyses of small-scale (microcentrifuge tube) versions of isothermal HWE worts showed good correlations with the attributes of Congress worts. Although the key malting quality metrics for Congress and HWE worts were not equivalent, their close correlations suggest that they may be equally able to differentiate the malting quality of barley lines. The simple isothermal temperature profile of the HWE wort, in conjunction with implementation of methods that use simple laboratory instrumentation for wort analysis, could simplify initial malting quality analysis and make it more accessible to laboratories lacking dedicated mashing and wort analysis instruments.