Empirical rheology and pasting properties of soft-textured durum wheat (Triticum turgidum ssp. durum) and hard-textured common wheat (T. aestivum)

Puroindoline (PIN) proteins are the molecular basis for wheat kernel texture classification and affect flour milling performance. This study investigated the effect of PINs on empirical rheology and pasting properties in Triticum turgidum ssp. durum and Triticum aestivum. Soft wheat (cv. Alpowa), durum wheat (cv. Svevo) and their derivatives in which PINs were deleted (Hard Alpowa) or expressed (cv. Soft Svevo). Presence of PINs affected flour particle size and damaged starch. PINs increased the pasting temperature and breakdown viscosity, while the effect on peak viscosity and setback were not consistent. Presence of PINs was negatively associated with GlutoPeak gluten aggregation energy and farinograph dough stability, suggesting a weakening of the gluten matrix. As regards dough extensibility, the role of PINs was evident only in common wheat: 5DS distal end deletion increased the resistance to extension, without affecting the dough extensibility. This study showed PINs to have different impact on pasting and rheological properties of T. aestivum and T. turgidum ssp. durum flours.