H. Wieser, Comparative investigations of gluten proteins from different wheat speciesI. Qualitative and quantitative composition of gluten protein types, EUR FOOD RE, 211(4), 2000, pp. 262-268
In contrast to the hexaploid common (bread) wheat, little information is av
ailable on the qualitative and quantitative compositions of gluten proteins
from other cultivated wheat species. Therefore, representatives of hexaplo
id spelt. tetraploid durum wheat and emmer, and diploid einkorn were compar
ed with three classes of common wheat (winter wheat, spring wheat, wheat ry
e hybrid). The flours were extracted to yield total endosperm proteins and
the gluten protein fractions (gliadins and glutenin subunits). The extracts
were characterised using sodium dodecyl sulfate polyacrylamide gel electro
phoresis and reversed-phase HPLC; both methods revealed that gluten protein
groups and types known from common wheat (omega-, alpha-, gamma-gliadins,
HMW and LMW subunits of glutenin) were present in all species. The HPLC pla
tterns of gliadins and glutenin subunits from species with the same genome
composition (common wheat/spelt or durum wheat/emmer) were related, and tho
se of einkorn quite different. According to the quantities determined by re
versed-phase HPLC, alpha-gliadins were predominant in most cases, followed
by gamma-gliadins and LMW subunits; omega-gliadins and HMW subunits were ge
nerally minor components. Common wheats were characterised by the highest p
roportions of total glutenins and HMW subunits- which are known to be impor
tant for breadmaking quality. Moreover, the lower ratio of gliadins to glut
enins was typical. Emmer had the lowest proportions of total glutenins and
of HMW and LMW subunits, together with einkorn the highest proportion of al
pha-gliadins, and, by far, the highest ratio of gliadins to glutenins. The
values for spelt and durum wheat were mostly in a medium range between comm
on wheats, emmer, and einkorn, respectively. Amongst common wheats, spring
wheat was characterised by more balanced quantities of alpha- and gamma-gli
adins, and wheat rye hybrid by the highest proportions of omega-gliadins.