Composition, protein contents and microstructural characterisation of grains and flours of Emmer wheats (Triticum turgidum ssp dicoccum) of the central italy type

Abstract

The microstructural characteristics were evaluated of two types of Italian Farro (Triticum turgidum ssp. dicoccum) with spring and autumn growth habits, the former with a vitreous tendency and the latter with a floury tendency. Common wheat flours and grains (Triticum aestivum) were used as controls. Protein fractions such as glutenin and gliadin were extracted from Triticum turgidum ssp. dicoccum flours and studied by SDS-PAGE in order to make a comparison between the electrophoretic analyses and microstructural studies which were conducted on the same samples using Scanning Electron Microscopy (SEM and Cryo-SEM). The results obtained by SDS-PAGE showed that the gliadin patterns of both emmer samples were similar, while the common wheat gliadins showed a band at 90 kD a that was not present in the gliadin fraction of emmer. When the glutenin patterns were analysed, the autumn emmer did not show the low molecular weight protein bands (16-23 kDa) whilst spring emmer wheat appeared more similar to common wheat. Regarding the microstructural characteristics of the kernels, spring (vitreous tendency) emmer showed starch granules covered by protein to a higher extent than autumn emmer. These differences were also observed in flours. The gluten of spring emmer wheat was observed as a homogeneous structure showing similarities with common wheat gluten, while autumnal emmer gluten appeared more heterogeneous and lacking in structure.