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BACKGROUND: Salted hen egg yolks are less oily and less flavorful than salted duck egg yolks. However, hen eggs have a more adequate market supply and have a broader application prospect than duck eggs. In the present study, egg yolks, plasma, and granules were dehydrated by adding 1% NaCl to simulate traditional curing process of salted egg yolk. The changes in the pickling process of hen egg yolks (HEY) and duck egg yolks (DEY) plasma and granules were compared to reveal the gelation mechanism and the underlying causes of quality differences in salted HEY and DEY. Salted HEY can be compared with the changes in DEY during the pickling process to provide a theoretical basis for the quality improvement of salted HEY to salted DEY. RESULTS: The results showed that both plasma and granules were involved in gel formation, but exhibited different aggregation behaviors. Based on the intermolecular forces, the HEY proteins achieved aggregation mainly through hydrophobic interactions and DEY proteins mainly through covalent binding. According to spin–spin relaxation time, HEY gels immobilized a large amount of lipid and interacted strongly with lipids. DEY gels showed much free lipid and had weak interaction with lipid. The microstructure showed that HEY proteins were easily unfolded to form a homogeneous three‐dimensional gel network structure after salting, whereas heterogeneous aggregates were formed to hinder the gel development in DEY. Changes in protein secondary structure content showed that pickling can promote the transformation of the α‐helices to β‐sheets structure in HEY gels, whereas more α‐helices structure was formed in DEY gels. CONCLUSION: The present study has demonstrated that different gelation behaviors of hen and duck egg yolk proteins (especially in plasma) through salting treatment led to the difference in the quality of salted HEY and DEY. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Water‐in‐oil‐in‐water (W1/O/W2) emulsions stabilized by protein–carbohydrate complexes were prepared from an inner water phase (W1), an oil phase (O) and an outer water phase (W2). The complexes consisted of heat‐induced aggregates (HIAs) of isomalto‐oligosaccharide/egg white protein Maillard conjugates. The effects of polyglycerol ester of polyricinoleic acid (PGPR) concentration, HIA concentration, W1‐to‐O volume ratio and W1/O‐to‐W2 volume ratio on the properties of the W1/O/W2 emulsions were systematically investigated. RESULTS: At sufficiently high PGPR concentrations (>2%), the emulsions possess a high negative charge (≈−44 mV). The encapsulation efficiency of the emulsions, which was determined by incorporating a hydrophilic yellow dye in the inner water phase prior to homogenization, was relatively high (up to 93%) and did not change significantly during 14‐day storage at 4 °C. All emulsions were fluids that exhibited shear thinning behavior. CONCLUSION: Overall, this study shows that nature‐derived emulsifiers can be used to create W1/O/W2 emulsions suitable for application in the food industry. In addition, we provided a viable strategy to encapsulate water‐soluble nutrients. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ovalbumin (OVA), accounting for 50% of proteins in egg white, is a kind of high‐quality protein with excellent nutritional and processing functions. Acid heat treatment will induce the deformation and filtration of OVA, endowing it with improved functionality. However, the molecular kinetic process during the fibrillation of OVA and the application of the fabricated OVA fibrils (OVAFs) have not been thoroughly studied and revealed. RESULTS: In this study, the fabrication mechanism and the application OVAFs as an interfacial stabilizer and polyphenol protector were investigated. Acidic (pH 3.0) heat treatment was used to induce the fibrillation of OVA, and thioflavin T fluorescence intensity, molecular weight distribution, and the tertiary and secondary structures of OVAF samples were recorded to determine the fibrillation efficiency and the molecular mechanism. The results showed that, in the initial stage of fibrillation, OVA first hydrolyzed to oligopeptides, accompanied by the exposure of hydrophobic domains. Then, oligopeptides were connected by disulfide bonds to form primary fibril monomers. Hydrophobic interaction and hydrogen bonding may participate in the further polymerization of the fibrils. The fabricated OVAFs were characterized by a β‐sheet‐rich structure and possessed improved emulsifying, foaming, and polyphenol protection ability. CONCLUSION: The research work was meaningful for exploring the application of globular water‐soluble OVA in an emerging nutritious food with novel texture and sensory properties. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Liquid eggs have the advantages of high hygiene security, easy use, and convenient transportation, but their shelf life is only limited to 2~3 weeks. The microbial, physiochemical, and functional properties of pasteurized LWE were investigated in this study to evaluate the quality of pasteurized liquid whole egg (LWE) during refrigerated storage. RESULTS: The tested shelf life of the pasteurized LWE was 16 days when stored at 4 °C. During refrigerated storage, Pseudomonas gradually became the dominant bacterium in LWE following lactic acid bacteria, although the initial number of Pseudomonas after pasteurization was relatively limited (< 10 CFU mL−1). A total of 23 strains, including six Pseudomonas strains, were obtained. The pH of pasteurized LWE decreased with the growth of microorganisms, while the content of total volatile basic nitrogen (TVB‐N) increased curvilinearly. The average particle size increased almost continuously until the sample reached its shelf life. The functional properties of pasteurized LWE were also reduced after a week of refrigerated storage at 4 °C when the microorganisms in pasteurized LWE entered an exponential growth period and the TVB‐N content of pasteurized LWE reached its first peak. CONCLUSION: During refrigerated storage, Pseudomonas was the dominant bacterium in LWE next to lactic acid bacteria. After a week of refrigerated storage at 4 °C, the particle size of LWE increased, while the functional properties of LWE reduced. This study provides a basis for extending the shelf life of liquid egg products in future research. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Soy protein isolate (SPI) is widely used as an alternative to animal‐based protein, and its gelling property is essential for producing plant protein‐based foods. Insoluble dietary fiber has been used to improve the properties of protein gels. RESULTS: Effects of partial replacement of SPI by okara dietary fiber (ODF) on the gelling properties of ODF‐fortified SPI gels with and without 0.1 m NaCl were investigated. The presence of ODF hindered the SPI self‐aggregation and reduced the surface hydrophobicity of SPI. The presence of ODF reduced the hydrophobic interaction and improved the proportion of disulfide bonds in the gels. In the microstructure, the swollen ODF promoted the local aggregation of SPI at 0.1 m NaCl. Texture profile analysis showed that 5% and 10% ODF improved the SPI gel hardness in the absence of NaCl, whereas only 5% ODF improved the gel hardness at 0.1 m NaCl. The results of low‐field nuclear magnetic resonance imaging revealed that ODF shortened the T2 relaxation time of the free water in the gel. The gel of ODF‐10 had the highest storage modulus. CONCLUSION: Using an appropriate amount of ODF to replace SPI could improve the quality of SPI gel and increase the dietary fiber content in the product. In addition, the appropriate ratio of ODF/SPI varied in different solution environments. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Isolation of lysozyme from egg white (EW) using ion exchange resin adsorption method generates large quantities of lysozyme‐free egg white (LFEW) with poor gelling property. To maximize the applications of LFEW, the effect of Lactiplantibacillus plantarum fermentation on the gel properties of LFEW was investigated in this study. RESULTS: The fermentation efficiency of LFEW with lysozyme removed was significantly improved, and the sugar removal rate (2 g kg−1Lactiplantibacillus plantarum, 37 °C, 7 h) was more than 90%. Removal of lysozyme resulted in increased stability and surface hydrophobicity of EW. After Lactiplantibacillus plantarum fermentation, the stability of EW decreased, and the average particle size and surface hydrophobicity increased. In addition, by comparing the gel properties of EW and LFEW before and after fermentation at different pH, it was found that the hardness, elasticity, and water holding capacity (WHC) of EW gel increased significantly. The removal of lysozyme effectively improved the WHC and springiness of the EW gel and promoted the formation of a denser network structure with smaller pores. After Lactiplantibacillus plantarum fermentation treatment, LFEW gel hardness decreased, with loose and porous network structure, no browning occurred after autoclaving. CONCLUSION: This study provided the direction and theoretical basis for producing a fermented LFEW gel with pleasing texture and appearance. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Egg yolk granules (EYGs)‐soy lecithin (SL) complex is a newly developed delivery system that is effective for improving the storage stability of hydrophobic bioactive compounds. However, the formation mechanism of EYGs and SL complex and its effect on the gastrointestinal fate of lutein‐loaded emulsions needs to be investigated further. RESULTS: Adding SL greatly improved the surface activity of the EYGs, as evidenced by reduced surface tension and an increased adsorption rate to the oil/water interface. Hydrophobic interaction was the dominant force in the formation of EYG‐SL complex, with hydrogen and ionic bonds playing complementary roles. Using the EYG‐SL complex, stable oil‐in‐water emulsions were formed and exhibited an enhanced retention ratio and bioaccessibility of lutein after simulated digestion. Correlation analysis demonstrated that the additional anti‐oxidant activity as a result of EYGs was responsible for the high retention of lutein, whereas low surface tension facilitated the micellization of bioaccessible lutein. CONCLUSION: The present study shows that the EYG and SL have a synergistic effect with respect to improving the retention ratio and bioaccessibility of lutein in emulsions stabilized by EYG‐SL complex after digestion and this will guide the development of value‐added oil‐in‐water emulsion products using protein‐lecithin complex as a promising nutrient delivery vehicle. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this work was to evaluate the effects of egg freshness on baking properties and final qualities in batter systems. Batters were made with eggs of different freshness, and the properties of batter systems were studied through rheological analysis, rapid viscosity analysis ( RVA), differential scanning calorimetry ( DSC), batter density and expansion rate during the baking and cooling processes. Moreover, the qualities of final baked systems were investigated, including specific volume and texture profile analysis ( TPA). RESULTS The flow behavior of batters showed that the consistency index ( K) decreased as the Haugh unit ( HU) value decreased, while the flow behavior index ( n) increased. Both the storage modulus ( G′) and loss modulus ( G″) determined by mechanical spectra at 20 °C decreased with decreasing HU. RVA and DSC determinations revealed that lower- HU samples had a lower viscosity in the baking process and a shorter time for starch gelatinization and egg protein denaturation. Observation of the batter density revealed an increasing change, which was reflected by a decrease in the specific volume of final models. TPA showed significant differences in hardness and chewiness, but no significant differences in springiness and cohesiveness were found. CONCLUSION The egg freshness affected the properties of batter systems. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Egg proteins are effective emulsifiers and gelators in food systems. However, the physicochemical stability and control release properties of egg‐protein stabilized emulsions and gels need to be further improved. The potential of sodium tripolyphosphate (St) to improve the functionality of egg proteins was evaluated. RESULTS: The emulsions with St had smaller particle sizes and higher zeta potential, leading to better physical stability. Furthermore, the oxidation stability increased with increasing St contents, possibly due to its metal chelating capacity and the improved emulsifying activity of whole‐egg dispersions. Phosphate had a positive impact on the chemical stability of β‐carotene in whole‐egg liquids and gels, decreasing the degradation during thermal treatment. The gel made with St was firm and broke down slowly, leading to a low rate of digestion and β‐carotene release in simulated gastric fluid. CONCLUSION: This study shows that St is useful to improve the egg proteins stabilized emulsions and gels, which is applicable in the development of emulsion‐based food grade gel products. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]