Endosperm Structure Affects the Malting Quality of Barley (Hordeum vulgare L.)

Abstract

Twenty-seven barley (Hordeum vulgare L.) samples collected from growing sites in Scandinavia in 2001 and 2002 were examined to study the effect of endosperm structure on malting behavior. Samples were micromalted, and several malt characteristics were measured. Samples were classified as having a mealier or steelier endosperm on the basis of light transflectance (LTm). Because endosperm structure is greatly dependent on protein content, three barley sample pairs with similar protein contents were chosen for further analysis. During malting, the steelier barley samples produced less root mass, but showed higher respiration losses and higher activities of starch-hydrolyzing enzymes. Malts made from steelier barley had a less friable structure, with more urea-soluble D hordein and more free amino nitrogen and soluble protein. The reason for these differences may lie in the structure or localization of the hordeins as well as the possible effects of endosperm packing on water uptake and movement of enzymes.

In situ study of water uptake by the seeds, endosperm and husk of barley using infrared spectroscopy

“…A lag phase between 10 and 15 min, followed by a second increase of water uptake between 30 and 60 min, was also observed. These results are in agreement with those reported by other authors [16,25,22,32]. The rate of water uptake (RWU) at 30 and 60 min for the same genotype (Admiral, Commander, Flagship and Navigator) harvested in two consecutive years was also calculated (see Fig.…”

Influence of barley variety, timing of nitrogen fertilisation and sunn pest infestation on malting and brewing

“…This could suggest a higher level of β‐glucan‐degrading enzymes in spring barleys and malts, which, however, is much dependent on the environmental conditions, but the β‐glucanase activity data did not confirm this theory 7. Moreover, it could be due to some structural differences in the endosperm that are associated with malting quality 29, 30. Brennan et al 31 observed that variation in glucanase activity was not related to variation in malting quality.…”

Importance of Endosperm Modification for Malt Wort Fermentability1

“…High barley protein concentration resulting from drought, excess available nitrogen or other environmental factors can severely alter the modification properties of a barley sample 19 . Hard kernels, often referred to as steely kernels, have also been shown to modify more slowly than mealy type kernels 17 . Processing conditions in the malthouse also have a marked effect on modification 23 .…”