Dielectric barrier discharge cold plasma combined with cross-linking: An innovative way to modify the multi-scale structure and physicochemical properties of corn starch

Cold plasma is a low-cost, simple and green method for starch modification. In the present study, the impact of corn starch modification by cold plasma (CP, 1, 3 and 9 min), sodium trimetaphosphate/sodium tripolyphosphate (CL, 1 %, 5 % and 10 %) and their combination were investigated. CP-pretreatment had enhancement of phosphorus content and substitution degree. Neither CP nor CL destroyed the starch granules morphology. Instead, CP induced more short-chain to better rearrange the starch during the crosslinking process, which improved the efficiency of the crosslinker in the subsequent crosslinking process. Therefore, compared with CL or CP, the thermal transition temperatures increased after CP pretreatment, while the amylose content, relative crystallinity, swelling power, and delta H decreased. Meanwhile, CP-pretreatment changed the internal structure of the CL-starch so that it showed the lowest enzymatic digestibility. CP pretreatment provides a promising way to improve cross-linked starch's structure, properties, and efficiency.

Automated summary

Cold plasma is a promising and environmentally friendly method for starch modification. The study found that pretreatment with cold plasma increased phosphorus content and substitution degree, leading to improved structure and properties of cross-linked starch.