Modification of corn starch via innovative contactless thermal effect from induced electric field

Growing attention has been focused on modifications of starch using electric field, but electrode corrosion and metal contamination remain unavoidable during the process. To solve these problems, the magneto-induced electric field was used to assist corn starch hydrolysis due to its thermal effect. Results indicated that the method accelerated corn starch acid hydrolysis and decreased the treatment time. The reducing sugar content increased to 0.59 g/L after a 60 s treatment, which was 353.44 % higher than the 20 s treatment, while the average degree of polymerization reached a minimum. The treated starch showed increased solubility and swelling power, as well as decreased freeze-thaw stability. X-ray diffraction, fourier transform infrared spectroscopy, and scanning electron microscopy results suggested that the physicochemical changes of corn starch were due to the thermal effect of the induced electric field. This study is expected to provide an important basis for applying new electric field hydrolysis technology to starch modification.