Sulphur fertilization of barley crops improves malt extract and fermentability

Abstract

It has been proposed that the composition of hordeins, besides grain protein content and grain size, is a determining factor of the malt extract, one of the most important criterions of barley malt quality. Six field experiments were conducted in the Pampean region in order to evaluate the effects of sulphur fertilization under different levels of nitrogen availability on the relative quantities of hordeins fractions in grains, and on malt extract and other malt quality parameters. Sulphur fertilization at a rate of 10 kg S ha−1 affected hordein composition, increased malt extract and apparent attenuation limit and decreased malt hardness but did not affect grain hordein and N concentration. Malt extract was associated more closely to grain N concentration and grain size than to hordein composition. In this study, where the same barley cultivar was used in all experiments, the composition of grain hordeins had a minor effect on the malt extract yield.