Physicochemical properties and 3D printability of pregelatinized corn starch were modulated through pulsed electric fields and ultrasonic treatments

Abstract

While US and PEF treatments have been studied for native corn starch, their effects on the 3D printing behavior of pregelatinizedcorn starch (PGCS) remain largely unexplored. This study is among the first to link these non-thermal treatments to enhancedfunctionality and printability of PGCS. Therefore, this study focused on the impact of US and PEF treatments on thephysicochemical properties and 3D printability of PGCS, which is significant for the development of customized food productsand innovative applications in the food industry. PGCS was subjected to US at amplitudes of 60%–90% for 30 min in 0.5 s on andoff cycles and PEF at an electric field of 9.4 kV/cm, 20 µs pulse width at a frequency of 20 Hz for 100–400 pulses. Both treatmentsdisrupted native granular architecture and induced changes in structural organization. US promoted amylose leaching, resultingin higher amylose contents (up to 36.18%) and improved water and oil absorption capacities (up to 3.86 and 5.37 g/g, respectively).PEF had minimal effect on composition but improved pasting viscosities and gel texture. X-ray diffraction (XRD) and differentialscanning calorimetry (DSC) results revealed reduced crystallinity and elevated gelatinization temperatures for modified PGCS.PEF-treated PGCS hydrogels exhibited improved gel hardness and rheological parameters correlated to high-fidelity, superior 3Dprinted constructs compared to weak US counterparts. Overall, modifications from both techniques enhanced functionalities,with PEF conferring rheological attributes preferable for 3D bioprinting PGCS-based foods. The findings highlight the potentialfor rationally manipulating the physicochemical and processing behavior of starch through non-thermal technologies.

The authors are grateful to the Spanish Ministry of Science and Innovationfor the funding of the project PID2021-123516OB-I00. This project hasreceived funding from the European Union’s Horizon 2020 researchand innovation programme under the Marie Skłodowska-Curie grantagreement No. 101034288.