Temperature of plasma-activated water and its effect on the thermal and chemical surface properties of cereal and tuber starches

High amylose and waxy starches from maize and potato were incubated with plasma-activated water (PAW) at 25 degrees C, 60 degrees C, and 80 degrees C temperatures to investigate PAW treatment effects on the starches' properties. At 60 degrees C incubation temperature, the starches were basically annealed with PAW. Annealing starches with PAW signifi-cantly increased (p < 0.05) the gelatinization parameters except for the enthalpy of gelatinization of waxy potato starch. Furthermore, starch swelling power significantly decreased while the water absorption capacity and solubility increased significantly when incubated at 80 degrees C. X-ray photoelectron spectroscopy (XPS) analysis showed the oxidation of C-C/C-H and C-O into carboxyl groups in waxy and high amylose maize starches incubated with PAW at 60 degrees C and 80 degrees C, respectively. In addition, cross-linking was observed in waxy maize and high amylose potato incubated with PAW at 80 degrees C and 25 degrees C, respectively. Overall, the results indicated PAW temperature is an important factor in modifying cereals and tuber starches with PAW.