Effects of cold atmospheric plasma on techno-functional properties of mechanically fluidized Teff flour

Teff [Eragostis tef (Zucc.) Trotter] has attracted much attention due to its gluten free and balanced nutritional benefits, but little work has been done to improve its techno-functional properties. The aim of this work was to evaluate the influence of a range of plasma treatment times on a variety of attributes of teff flour: physicochemical, thermal, rheological, gel-hydration and pasting properties. To ensure maximum exposure of the teff to the plasma products, the powder was suspended and dispersed in a closed treatment chamber in a fan-generated current flow. Untreated (control) and cold plasma treated samples (for 5, 10, 20 and 30 min) were analyzed for their amylose content, starch damage, FTIR and technological properties (steady shear viscosity, hydration properties, thermal analysis and pasting properties). The longer time led to a stronger depolymerization of the starch damage and a weakening of the gel structure, so that the swelling capacity, solubility and water absorption capacity increased. The cold plasma technique had no effect on the gelatinization temperature (To, Tm and Tc), but a significant (P < 0.05) influence on the enthalpy. The extended treatment time also affected the adhesive properties and flow properties. This study suggests that cold plasma technology can be useful in the tailored modification of teff flour to produce products with different technological properties.