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This study explored the effect of constant-current pulsed electric field thawing (CC-T) on the proteins and water-holding capacity of pork. Fresh meat (FM), and frozen meat after constant-voltage thawing (CV-T), air thawing (AT) and water immersion thawing (WT) were considered as controls. The results indicated that CC-T had a higher thawing rate than conventional thawing during ice-crystal melting stage (−5 to −1 °C). It also showed a lower water migration and thawing loss, maintaining pH and shear force closer to FM. Meanwhile, CC-T decreased myoglobin oxidation, resulting in a favorable surface color. The results of protein solubility, differential scanning calorimetry, total sulfhydryl, carbonyl and surface hydrophobicity demonstrated that CC-T reduced myofibrillar protein oxidative denaturation by suppressing the formation of disulfide and carbonyl bonds, thus enhancing solubility and thermal stability. Additionally, microstructural observation found that CC-T maintained a relatively intact muscle fiber structure by reducing muscle damage and myosin filament denaturation. [Display omitted] • CC-T reduced the conversion of immobilized water to free water in the meat. • CC-T resulted in higher protein solubility and thermal stability than AT and WT. • CC-T had a lower degree of myofibrillar protein oxidation compared to AT and WT. • CC-T resulted in less muscle tissue damage, making the fiber structure more complete. [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]

• IEF-assisted hydrolysis enhanced with increasing DD of chitosan. • Electrical properties of chitosan showed no significant effect on the hydrolysis. • Structural compactness determined the hydrolysis behavior of different-DD chitosan. This study explored the impact of re-acetylation on induced electric field (IEF)-assisted hydrolysis of chitosan. Chitosan with different degree of deacetylation (DD) exhibited different charge content but similar electrical conductivity and output voltage of the electrolyte system, thus theoretically resulting in equivalent electro-processing efficiency. However, molecular and rheological measurements suggested that the hydrolysis rate decreased with an increase of DD. Re-acetylation had no significant effect on the molecular weight and viscosity of chitosan but damaged its granular and crystal structure, making chitosan chains more susceptible to the acid. The IEF-assisted hydrolysis of dissolved chitosan confirmed that the structural compactness of chitosan played a more important role on the hydrolysis than the charge content. This study extended current knowledge regarding the effect of charge content and structural compactness on IEF-assisted hydrolysis process, which contributed to the applications of IEF in biopolymer modification. [ABSTRACT FROM AUTHOR]