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To develop natural complex materials as starch-dominated emulsifiers, pregelatinization was conducted on potato flour. The effects of gelatinization degrees (GDs, 0 %–50 %) on the structural characteristics, physicochemical properties, and emulsifying potentials of potato flour were investigated. Increasing GD of potato flour promoted protein aggregation on starch granules surfaces and transformed starch semicrystalline structures into melted networks. The emulsion stabilized with 50 % GD potato flour exhibited excellent storage stability (7 d) and gel-like behavior. With increasing GD from 0 to 50 %, the respective apparent viscosities and elastic moduli of emulsion increased from 21.4 Pa to 1126.7 Pa, and from 0.133 Pa·s to 1176.6 Pa·s, promoting the formation of a stable network structure in the emulsion. Fourier transform infrared spectra from emulsions with a continuous phase of >20 % GD displayed a new peak around 1740 cm−1, suggesting improved covalent interactions between droplets, thereby facilitating emulsion stability. Confocal laser scanning microscopy images indicated that droplets could be anchored in the melted networks and broken starch granules, inhibiting droplets coalescence. These results suggest that pregelatinization is a viable strategy for customizing natural starch-dominated emulsions. [Display omitted] • Emulsions stabilized by pregelatinized potato flour were successfully fabricated. • Proteins were aggregated on the surface of starch in the gelatinized potato flour. • Increased gelatinization degree of potato flour enhanced the stability of emulsion. • The enhancement of emulsification was due to increasing interactions of components. [ABSTRACT FROM AUTHOR]

Glutinous sorghum grains were soaked (60–80 °C, 2–8 h) to explore the effects of soaking, an essential step in industrial processing of brewing, on starch. As the soaking temperature increased, the peak viscosity and crystallinity of starch gradually decreased, while the enzymatic hydrolysis rate and storage modulus first increased and then decreased. At 70 °C, the content of amylose, the enzymatic hydrolysis rate of starch, and the final viscosity first increase and then decrease with the increase of soaking time, reaching their maximum at 6 h, increased by 53.1 %, 11.0 %, and 10.4 %, respectively, as compared with the non-soaked sample. At 80 °C (4 h), the laser confocal microscopy images showed a network structure formed between the denatured protein chains and the leached-out amylose chains. The molecular weights of starch before and after soaking were all in the range of 3.82–8.98 × 107 g/mol. Since 70 °C is lower than that of starch gelatinization and protein denaturation, when soaking for 6 h, the enzymatic hydrolysis rate of starch is the highest, and the growth of miscellaneous bacteria is inhibited, which is beneficial for subsequent processing technology. The result provides a theoretical basis for the intelligent control of glutinous sorghum brewing. [Display omitted] • Soaking at 70 °C for 6 h, the enzymatic hydrolysis rate of starch is the highest. • As the soaking temperature increases, the starch granules swell, deform and break. • Networks formed between starch and protein by soaking glutinous sorghum. [ABSTRACT FROM AUTHOR]

Kudzu, a plant known for its medicinal value and health benefits, is typically consumed in the form of starch. However, the use of native kudzu starch is limited by its high pasting temperature and low solubility, leading to a poor consumer experience. In this study, kudzu starch was treated using six modification techniques: ball milling, extrusion puffing, alcoholic-alkaline, urea-alkaline, pullulanase, and extrusion puffing-pullulanase. The results of the Fourier transform infrared spectrum showed that the intensity ratio of 1047/1022 cm−1 for the modified starches (1.02–1.21) was lower than that of the native kudzu starch (1.22). The relative crystallinity of modified kudzu starch significantly decreased, especially after ball milling, extrusion puffing, and alcoholic-alkaline treatment. Furthermore, scanning electron microscopy and confocal laser scanning microscopy revealed significant changes in the granular structures of the modified starches. After modification, the pasting temperature of kudzu starch decreased (except for the urea-alkaline treatment), and the apparent viscosity of kudzu starch decreased from 517.95 Pa·s to 0.47 Pa·s. The cold-water solubility of extrusion-puffing and extrusion puffing-pullulanase modified kudzu starch was >70 %, which was significantly higher than that of the native starch (0.11 %). These findings establish a theoretical basis for the potential development of instant kudzu powder. • Effect of six modification methods on the structural properties of kudzu starch • The cold-water solubility of starch increased by 700 times after extrusion puffing. • Six modification methods positively affected the properties of kudzu starch. • Six modifications reduced the pasting temperature of kudzu starch. [ABSTRACT FROM AUTHOR]

Enzyme immobilization usually make use of nanomaterials to hold up biocatalysis stability in various unamiable reaction conditions, but also lead large discount on enzyme activity. Thus, there are abundant researches focus on how to deal with the relation of enzyme molecules and supports. In this work, a new state of highly active enzymes has been established through facile and novel in situ immobilization and soft template removal method to construct enzyme contained hollow silica nanosphere (catalase@HSN) biocatalysts where enzymes in the cavity exhibit "immobilized but not rigid state". The obtained catalase@HSN was characterized by transmission electron microscopy, scanning electron microscopy and confocal laser scanning microscopy et al. Catalase@HSN exhibits excellent activity (about 80 % activity recovery rate) and stability suffers from extreme pH, temperature, and organic solvents. Moreover, the reusability and storage stability of catalase@HSN also are satisfactory. This proposed strategy provides a facile method for preparing biocatalysts under mild conditions, facilitating the applications of immobilized enzyme in the fields of real biocatalytic industry with high apparent activity and passable stability. A new state of highly active enzymes has been established through soft template removal method to construct enzyme contained hollow silica nanosphere (enzyme@HSN) biocatalysts where enzymes in the cavity exhibit "immobilized but not rigid state". [Display omitted] • Hybrid MOF using glutathione as alternative ligand was used as self-sacrificial template for hollow silica fabrication. • Enzyme molecules in hollow silica nanosphere are "Immobilized but Not Rigid State" with improved activity. • This proposed strategy provides a facile method for preparing nano-biocatalysts under mild conditions. [ABSTRACT FROM AUTHOR]

We herein evaluated the impact of adding wheat bran dietary fiber (WBDF) on the aggregation behavior of gluten in dough at various stages of the noodle-making process. Scanning electron microscopy and confocal laser scanning microscopy images confirmed the effective insertion of WBDF particles into the gluten matrix. Importantly, the gap between WBDF and gluten widened during the rolling process. The addition of WBDF led to a reduction in glutenin macropolymer (GMP) content and an elevation in sulfhydryl content, induced the depolymerization behaviors at the molecular level. Additionally, it facilitated the conversion of α-helices and β-turns into β-sheets and random coils within the dough. Moreover, the processing and addition of WBDF contributed to a decrease in weight loss, whereas the degradation temperature remained constant. Resting decreased the sulfhydryl content, whereas sheeting and cutting increased it, further fostering protein depolymerization in the presence of WBDF. These actions significantly increased the β-sheets and random coils content at the expense of β-turns and α-helices content. Significantly, controlled processing emerged as a crucial factor in enhancing gluten depolymerization induced by WBDF in the dough. This comprehensive study provides a nuanced perspective on controlling dough processing to strike a balance between dietary fiber-rich and high-quality foods. • GMP revealed that WBDF addition level had more influence than noodle-making process. • WBDF, and sheeting and cutting induced the transformation of α-helix and β-turn into β-sheet and random coil structure. • Resting resulted in a more uniform gluten network. • WBDF and processing had a synergistic effect on the gluten aggregation behavior of the dough. [ABSTRACT FROM AUTHOR]