Effects of various microwave intensities collaborated with different cold plasma duration time on structural, physicochemical, and digestive properties of lotus root starch

Lotus root starch was treated with single and combined microwave (300 and 700 W) and cold plasma (60, 90, and 120 s) treatments. Effects of treatments on multi-structural, physicochemical, and digestive properties of lotus root starch were investigated. The results revealed that a combination of cold plasma and microwave treatments significantly affected the morphology of starch granules and reduced the relative crystallinity of starch compared with a single treatment. However, no changes were found in the chemical functional groups of starch after single or combined treatments. Additionally, the amylose content, amylopectin branch chain length distribution, solubility, and swelling power of the starch significantly varied depending on cold plasma treatment duration and microwave power. Furthermore, the treated starch showed lower peak viscosity and higher pasting temperature than the native one. Moreover, the resistant starch content significantly decreased as cold plasma treatment was prolonged and microwave power increased.