| Abstract
| - Strains of fungi from different origins, including isolates of the natural microflora of barley, werescreened for their ability to modify barley starchy endosperm cell walls in situ. In an initial step,fungi were selected that degrade the major component of the cell walls, that is, (1→3),(1→4)-β-d-glucan, in vitro on artificial media. Nongerminating, sterilized barley, obtained by γ-irradiation,was inoculated with such fungi and subjected to solid state fermentation under conditions resemblingthose of a traditional malting process. For some strains of fungi, a clear correlation between theproduction of endo-β-glucanase and the friability of the treated kernels was found. Image analysisof Calcofluor stained longitudinal sections of barley kernels fermented with the endo-β-glucanaseproducing strains showed that starchy endosperm cell walls were modified. As malt quality isinversely related to its (1→3),(1→4)-β-d-glucan content, the selected strains have high potential tobe used as starter cultures during malt production, contributing to the processing quality of thefinal product. Keywords: Barley malt quality; cell wall modification; starter culture selection
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