A new pre-gelatinized starch preparing by spray drying and electron beam irradiation of oat starch.

As a green and safe physical technology, irradiation is increasingly used to improve starch properties. In the study, oat starch was pre-gelatinized at 70 °C followed by spray drying. Subsequently, the spray-dried starch (SDS) was exposed to electron beam (e-beam) irradiation at different doses to obtain new pre-gelatinized starch. Spray drying caused a decrement in the ratio of long B3 chains and the molecular weight of starch. Spray-dried starch (SDS) slightly increased solubility and swelling power than native starch. When SDS was subjected to e-beam irradiation, its solubility and swelling power increased dramatically, but the pasting viscosities, gelatinization temperatures, apparent viscosity, storage modulus (G') and lost modulus (G″) reduced. The depolymerization of starch molecules and the breakage of amylopectin chains might be responsible for changing the physicochemical properties of e-beam irradiated starch. These results showed that spray drying combined with e-beam irradiation would potentially produce new pre-gelatinized starch.