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A novel electromagnetic heat extraction method was presented, whereby mandarin peels residue solution was located in a winding coil subjected to an oscillating magnetic field, and the pectin was extracted under appropriate conditions. Numerical relationships between applied magnetic field and induced electric field (IEF) in the extraction process were elaborated. The results showed that the induced current density, IEF and terminal temperature increased with increasing magnetic field. The maximum current density of 0.35 A/cm corresponds to the highest terminal temperature of 84.6 °C and IEF intensity of 26.6 V/cm. When magnetic field intensity was 1.39 T and the extraction time was 15 min, the maximum yield of pectin reached 9.16 %. In addition, all treatments impacted the ash content, protein content, water-holding capacity (WHC), and oil-holding capacity (OHC) of the obtained pectin. The pectin extracted by electromagnetic heat had the lowest DE value of 71.3 % with 126.55 kDa molecular weight, while the GalA content was at the highest level of 76.18 %. After different treatments, the composition of pectin monosaccharides changed, but there were slight differences in the composition of pectin polysaccharides. Moreover, the electromagnetic heat extracted pectin had light color and an obvious surface fragmentation of the peel residue. [Display omitted] • Novel electromagnetic heat method was presented for the extraction of pectin. • The maximum yield of pectin reached 9.16 % at 1.39 T and 15 min. • Electromagnetic heat extracted pectin had brighter color and highest GalA level. • There were slight differences in the composition of polysaccharides. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effect of induced electric field (IEF) treatment on acid hydrolysis of corn starch by altering the connection modes of sample coils of a 4-reactor IEF system. Results suggested that IEF treatment could enhance the hydrolysis of corn starch and series connection (1. RRRR, η = 16 E Si 2 P in 4 Z Si + Z load ) exhibited higher energy efficiency than parallel (9. (RRRR), η = 4 E Si 2 P in Z Si + 4 Z load ), thus contributing to more extensive hydrolysis. Although no new functional group was formed, the starch granules were partially cracked into pieces and the crystallinity was slightly increased after IEF-assisted hydrolysis. Differential scanning calorimetry results indicated that IEF-assisted hydrolysis increased the gelatinization temperatures but decreased the enthalpy of starch, with a greatest variation was observed by series connection. Rapid visco-analysis showed that IEF-assisted hydrolysis greatly decreased the pasting viscosity of corn starch and also series connection showed the strongest reduction. The obtained results could provide a theoretical guide for the applications of IEF technology in biomaterial processing. [Display omitted] • Induced electric field (IEF) could enhance the acid hydrolysis of corn starch. • IEF-assisted hydrolysis highly depends on the energy efficiency of IEF system. • Series connection of IEF reactors showed the highest energy efficiency. • IEF-assisted hydrolysis largely decreased the pasting viscosity of corn starch. • IEF-assisted hydrolysis increased gelatinization temperatures but decreased enthalpy. [ABSTRACT FROM AUTHOR]

The induced electric field assisted hydrochloric acid (IEF-HCl) hydrolysis of potato starch was investigated in a fluidic system. The impact of various reaction parameters on the hydrolysis rate, including reactor number (1–4), salt type (KCl, MgCl 2 , FeCl 3 ), salt concentration (3–12%), temperature (40–55 °C), and hydrolysis time (0–60 h), were comprehensively assessed. Under optimal conditions, the maximum reducing sugar content in the hydrolysates was 10.59 g/L. X-ray diffraction suggested that the crystallinity of IEF-HCl-modified starches increased with the intensification of hydrolysis but was lower than that of native starch. Scanning electron microscopy indicated that the surface and interior regions of starch granules were disrupted by the hydrolysis. The solubility of IEF-HCl-modified starches increased compared to native starch while their swelling power decreased, contributing to a decline in paste viscosity. These results suggest that IEF is a notable potential electrotechnology to conventional hydrolysis under mild conditions without any electrode touching the subject. [ABSTRACT FROM AUTHOR]

The effects of induced electric field (IEF) on the crystal structure and physicochemical properties of potato starch were investigated by subjecting identically treated control and electrically-modified samples to the same temperature history. Additionally, a method of combining IEF with heating for efficient modification of native polymer was also proposed. Results showed that the application of IEF at an electric voltage of 75 V has a statistically significant effect on starch gelatinization and pasting properties, especially when combined with heating at 50 °C. After treatment by the combination method for 96 h, the gelatinization temperatures increased, which can be explained by the slight increase in the ratio of 1044/1015 cm −1 and relative crystallinity. Furthermore, IEF reduced granular swelling and therefore contributed to decreasing the peak, breakdown, and setback viscosity of potato starch. This study explores the potential of IEF as innovative technology for starch modification. [ABSTRACT FROM AUTHOR]