Voltage-dependent effects of DBD cold plasma on corn, sago, and tapioca starches: physicochemical and structural–functional characterization

Dielectric barrier discharge (DBD) cold plasma is a non-thermal approach for tailoring starch functionality. This study comparatively quantifies voltage-dependent responses (5–14 kV) of corn, sago, and tapioca starches under identical DBD conditions. Increasing voltage intensified oxidative reactions, with ozone rising from 0.0 to > 20 ppm. Moderate voltages (5–8 kV) enhanced hydration and leaching, increasing water absorption (WAI) by 12.02–22.66 and solubility by 14.28–42.22 versus native starches, whereas higher voltages (11–14 kV) reduced solubility by 5.55–61.84 and increased gel rigidity. Power-law parameters varied with voltage (K: 112.79–964.23; n: 0.415–1.047). Crystalline polymorphs were largely preserved, with relative crystallinity within 29.91–38.08, although corn starch was more structurally sensitive than tapioca and sago. Overall, the main outcome is identification of a controllable voltage range that shifts the dominant mechanism from hydration/solubility enhancement (5–8 kV) to oxidation-driven strengthening (11–14 kV), supporting reagent-free starch upgrading for food and biopolymer applications. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2026.