Facile production of low-viscosity mung bean starch through cold plasma treatment: Improvement of film formability.

Mung bean starch (MBS) has a strong potential to be used as food packages. However, preparing tough and uniform MBS films via industrial casting remains challenging due to the high viscosity of MBS slurry. Herein, MBS was modified by using dielectric barrier discharge cold plasma (CP) in an attempt to decrease its viscosity and improve the film-forming properties. Results indicated that CP with an applied power of 120 W for 5 min decreased the peaking viscosity of MBS slurry from 2936.5 to 466.3 cP. Moreover, CP treatment simultaneously modified the crystallinity (20.2%-16.7%), amylose content (30.5%-44.3%), and short-range orders (1.04-0.85). CP also broke the protective envelope of MBS granules. Further, the film-forming properties of MBS were investigated. It was observed that CP-modified MBS film casts exhibited uniform morphology, higher tensile strength (6.6-9.6 MPa), and improved thermal stability (89.0-100.8°C) compared with the untreated MBS film. The study indicates that the CP can be used as a green and facile technology to improve the properties of MBS films resulting in an efficient food packing material.