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In order to provide an efficient calcium transporter for the development of calcium supplement products, embryo eggs were selected for incubation. Carrying out calcium ions chelation on the embryo egg-derived egg white peptides (EED-EWPs) with high calcium binding activity produced incubation. The changes of EED-EWPs before and after chelation with calcium ions were compared, ζ-potential absolute value increased significantly, indicating that the embryo egg-derived egg white peptides calcium chelates (EED-EWPs-Ca) was successfully formed. Calcium binding activity results displayed that EED-EWPs on the 9th day of incubation had the highest calcium binding ability (6.96 μg/mg), which was 1.17 times that before incubation (5.97 μg/mg). EED-EWPs were isolated by IMAC metal chelating preloaded column, calcium binding amount was improved to 17.88 μg/mg, which was about 3 times that of those before isolation. The EED-EWPs were analyzed by mass spectrometry, six peptides with high calcium binding ability were identified. The mechanism of promoting calcium absorption of EED-EWPs produced during incubation was investigated by molecular docking with TRPV6 (a key protein for calcium transporter in the human small intestine). Results elucidated that amino and carboxyl groups in EED-EWPs were possible sites for calcium ions binding. This study would provide an efficient calcium transporter with high nutritional value for the development of calcium supplement products. [ABSTRACT FROM AUTHOR]

The effect of different glycosylation degrees on molecular structure and foaming property of egg white protein (EWP) was investigated using ball milling‐assisted glycosylation. The results showed the foaming ability (FA) and foam stability (FS) of EWP improved when the degree of glycosylation was increased. In particular, FA of ball milling‐assisted glycosylation of EWP enhanced by 39.9% and 28.8%, and the FS increased by 28.7% and 24.0% compared with EWP and ball milling egg white protein (BE) at 150 min of reaction. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) analysis could reflect the grafting degree of EWP and glucose molecules from the side. When EWP was fully grafted with glucose, endogenous fluorescence and free sulfhydryl groups indicated that tertiary structure of EWP was depolymerized, and Fourier transform infrared spectroscopy showed the secondary structure tended to change from order to disorder. The results of this study indicated that ball milling‐assisted glycosylation modification was a practical method to improve the foaming property of EWP. Practical Application: EWP has great FA and FS, making it indispensable in the baking industry. In this study, ball milling‐assisted glycosylation was used to improve the foaming property of EWP, and the molecular structure of EWP with different degrees of glycosylation was fully resolved. The results demonstrated that ball milling, as a physical pretreatment, can fully unfold the structure of EWP. When sugar molecules were fully grafted, the particle size of EWP reduced, solubility increased, and the stability of system improved, thus enhancing the foaming property of EWP. The results can provide theoretical basis for improving the foaming property of EWP and provide a reference value for its industrial application. [ABSTRACT FROM AUTHOR]

Egg white is often used in various food products because of its good functional properties such as gelling, foaming and emulsifying. In this article, heat treatment（30, 40, 50, 60 °C, 10 min）was employed to investigate the effects on the functional, physicochemical and molecular properties of thick egg white (KEW) comprehensively. The heat treatment caused the hardness, springiness, viscosity, and particle size of KEW to decrease and then increase. According to the results of surface hydrophobicity, sulfhydryl content and fluorescence spectroscopy, the protein structure expanded and then further aggregated after heat treatment with the exposure of the reactive group. The solubility, foaming capacity and emulsifying capacity of KEW were improved by heat treatment. The result of Fourier transformed infrared spectroscopy (FT-IR) showed that the heat treatment changed the structure of KEW from ordered to disordered. The heat treatment did not change the protein composition of KEW based on SDS-PAGE. • Heat treatment improved the solubility, foaming property and emulsifying activity of KEW. • Heat treatment changed the secondary structure of KEW from order to disorder. • The changes in functional properties of KEW caused by heating treatment were related to the changes in protein structure. [ABSTRACT FROM AUTHOR]

In order to further improve the functional properties of egg white protein powder (EWP), the effects of ball-milling pretreatment on the functional properties of EWP by glycosylation modification were studied. The results manifested that glycosylation reaction was successful. Compared with CEWP (glycosylated egg white protein powder without ball-milling pretreatment), BCEWP (glycosylated egg white protein powder after ball-milling pretreatment) showed lower free amino acid content and higher solubility. The results indicated that ball-milling pretreatment changed the secondary and tertiary structures of protein then prominently enhanced the degree of glycosylation reaction of EWP. Foaming ability of BCEWP (203.3%) was 1.12 times higher than that of CEWP (182.2%). The water holding capacity (WHC) of BCEWP (104.77%) was significantly larger than that of CEWP (100.28%), besides, BCEWP had greater gel springiness than CEWP. These results confirmed that ball-milling was an effective pretreatment to enhance the foaming and gel properties of EWP by glycosylation modification. [Display omitted] • Ball-milling pretreatment changed the egg white protein (EWP) structure. • The degree of glycosylation reaction of EWP was significantly increased after ball-milling. • Ball-milling is an effective pretreatment of glycosylation modified the foaming properties of EWP. • Ball-milling pretreatment glycosylation prominently improved the gel properties of EWP. [ABSTRACT FROM AUTHOR]