Dual sequential action of RF plasma and EBI decreased synergistically the viscosity.

Dual modification caused a synergistic decrease in molecular weights.

Dual modification led to slight variations in crystal short-range order structure.

Synergistic ratio had the highest values when RF plasma preceded irradiation.

Synergistic impact, irrespective of treatment sequence, was significant up to 10 kGy.

The impact of dual sequential modifications using radio-frequency (RF) plasma and electron beam irradiation (EBI) on starch properties was investigated and compared with single treatments within an irradiation dose range of 5–20 kGy. Regardless of sequence, dual treatments synergistically affected starch properties, increasing acidity, solubility, and paste clarity, while decreasing rheological features with increasing irradiation dose. The molecular weight distribution was also synergistically influenced. Amylopectin distribution broadened particularly below 10 kGy. Amylose narrowed its distribution across all irradiation doses. This was due to dominating EBI-induced degradation and molecular rearrangements from RF plasma. With the highest average radiation-chemical yield (G) and degradation rate constant (k) of (2.12 ± 0.14) × 10−6 mol·J−1 and (3.43 ± 0.23) × 10−4 kGy−1, respectively, upon RF plasma pre-treatment, amylose underwent random chain scission. In comparison to single treatments, dual modification caused minor alterations in spectral characteristics and crystal short-range order structure, along with increased granule aggregation and surface irregularities. The synergistic effect was dose-dependent, significant up to 10 kGy, irrespective of treatment sequence. The highest synergistic ratio was observed when RF plasma preceded irradiation, demonstrating the superior efficiency of plasma pre-treatment in combination with EBI. This synergy has the potential to lower costs and extend starch's technological uses by enhancing radiation sensitivity and reducing the irradiation dose.

radio-frequency plasma treatment followed by electron beam irradiation

electron beam irradiation

electron beam irradiation followed by radio-frequency plasma

Corn starch

Half-value dose

Ionizing radiation

Radio-frequency plasma

Synergy

Treatment sequence

© 2024 The Authors. Published by Elsevier B.V.