A promising food-grade protector for Retinyl acetate emulsions with fibrillated egg white.

This work presents a novel use of fibrous egg white protein (FEWP) in food preservation and nutraceutical applications. In this study, food-grade FEWP was used as an encapsulating material, along with chitosan (CS), to stabilize emulsions. The emulsion system was then used as a delivery system to improve the stability of retinyl acetate (RA). The structural and functional properties, as well as the stability and rheological behavior of the FEWP/CS copolymer, was investigated. The stability of RA-enriched emulsions was also evaluated. FEWP and CS stabilized emulsions exhibited smaller particle size and enhanced stability against different ionic strengths and storage periods. Additionally, RA-encapsulated emulsions stabilized by FEWP:CS (25:1 w/w) effectively inhibited apple browning. This study provides a promising strategy for delivering antioxidant components, highlighting its potential in food preservation and nutraceutical applications.

New evidence for gut-muscle axis: Lactic acid bacteria-induced gut microbiota regulates duck meat flavor.

The interaction between gut microbiota and muscles through the gut-muscle axis has received increasing attention. This study attempted to address existing research gaps by investigating the effects of gut microbiota on meat flavor. Specifically, lactic acid bacteria were administered to ducks, and the results of e-nose and e-tongue showed significantly enhanced meat flavor in the treatment group. Further analyses using GC-MS revealed an increase in 6 characteristic volatile flavor compounds, including pentanal, hexanal, heptanal, 1-octen-3-ol, 2,3-octanedione, and 2-pentylfuran. Linoleic acid was identified as the key fatty acid that influences meat flavor. Metagenomic and transcriptomic results further confirmed that cecal microbiota affects the duck meat flavor by regulating the metabolic pathways of fatty acids and amino acids, especially ACACB was related to fatty acid biosynthesis and ACAT2, ALDH1A1 with fatty acid degradation. This study sheds light on a novel approach to improving the flavor of animal-derived food.

Promoting effect of phosvitin in the mineralization of eggshell inner membrane with the application in osteogenic induction scaffold.

Exploring affordable and easily prepared inorganic-organic hybrid membrane materials has attracted a great interest in the bone repair field. This study is based on biomimetic mineralization technique to study the role of phosvitin (PV) in the mineralized process of eggshell inner membrane. Results showed that PV promoted the formation of hydroxyapatite on the eggshell inner membrane surface, and the phosvitin content in the simulated body fluid was decreased during the mineralization process. Besides, in vitro preosteoblast experiments indicated that mineralized membrane with PV exhibited more conducive to cell proliferation and differentiation than that mineralized membrane without PV. Interestingly, with the increase of mineralization time, the stimulating ability of mineralized membranes with PV on adhesion, proliferation, alkaline phosphatase activity and collagen type I content gradually improved. In summary, the eggshell inner membrane composites mineralized with PV obtained by biomimetic mineralization might be potential scaffold materials for bone repair.

Sucrose-phosphate osmotic system improves the quality characteristics of reduced-salt salted egg yolk: Profiling from protein structure and lipid distribution perspective.

This paper was dedicated to the study of the effect of sucrose-phosphate on aspects of physicochemical properties, lipid distribution and protein structure during the picklig of reduced-salt salted egg yolk (SEY). This work constructed a reduced-salt pickling system from a new perspective (promoting osmosis) by using a sucrose-phosphate-salt. Results showed that SEY-28d achieved a desirable salt content (1.07 %), hardness (573.46 g) and springiness (0.65 g). The matured SEY was in excellent quality with orange-red color and loose sandy texture. This was because the lipoprotein aggregated with each other through hydrophobic interaction to form a stable network structure. In addition, the hypertonic environment accelerated salt penetration. These also created good condition for lipid spillage. The results of confocal laser scanning microscope also verified this phenomenon. This work provides important guidance for new reduced-salt curing of traditional pickled foods, deep processing of SEY, and industry development in the field of poultry egg.

Alterations in gut and genital microbiota associated with gynecological diseases: a systematic review and meta-analysis.

BACKGROUND: Increasing number of studies have demonstrated certain patterns of microbial changes in gynecological diseases; however, the interaction between them remains unclear. To evaluate the consistency or specificity across multiple studies on different gynecological diseases and microbial alterations at different sites of the body (gut and genital tract), we conducted a systematic review and meta-analysis. METHODS: We searched PubMed, Embase, Web of Science, and Cochrane Library up to December 5, 2022(PROSPERO: CRD42023400205). Eligible studies focused on gynecological diseases in adult women, applied next-generation sequencing on microbiome, and reported outcomes including alpha or beta diversity or relative abundance. The random-effects model on standardized mean difference (SMD) was conducted using the inverse-variance method for alpha diversity indices. RESULTS: Of 3327 unique articles, 87 eligible studies were included. Significant decreases were found in gut microbiome of patients versus controls (observed species SMD=-0.35; 95%CI, -0.62 to -0.09; Shannon index SMD=-0.23; 95%CI, -0.40 to -0.06), whereas significant increases were observed in vaginal microbiome (Chao1 SMD = 1.15; 95%CI, 0.74 to 1.56; Shannon index SMD = 0.51; 95%CI, 0.16 to 0.86). Most studies of different diagnostic categories showed no significant differences in beta diversity. Disease specificity was observed, but almost all the changes were only replicated in three studies, except for the increased Aerococcus in bacterial vaginosis (BV). Patients with major gynecological diseases shared the enrichment of Prevotella and depletion of Lactobacillus, and an overlap in microbes was implied between BV, cervical intraepithelial neoplasia, and cervical cancer. CONCLUSIONS: These findings demonstrated an association between alterations in gut and genital microbiota and gynecological diseases. The most observed results were shared alterations across diseases rather than disease-specific alterations. Therefore, further investigation is required to identify specific biomarkers for diagnosis and treatment in the future.

Effects of lactic acid bacteria-derived fermented feed on the taste and quality of duck meat.

The present study aimed to examine the impact of lactic acid bacteria- fermented feed (FF) on the taste and quality of duck meat, in addition to elucidating the potential metabolomic mechanism at play. The findings revealed that ducks fed with FF exhibited elevated pH levels and reduced cooking loss in their meat when compared to the control group. In addition, the sensory evaluation and e-tongue analysis revealed that the tenderness, juiciness, umami, richness, saltiness, and sweetness of duck meat were all enhanced by feeding FF. Moreover, an examination of the metabolome using 1H nuclear magnetic resonance (1H NMR) identified the principal differential metabolites that exhibited a correlation with taste, which included 2-aminoadipate, glucose, glycine, N-acetylcysteine, niacinamide, proline, and threonine. Furthermore, the differential metabolites that exhibited the greatest enrichment in duck meat could be primarily traced to glutathione metabolism, glycine, serine and threonine metabolism, taurine and hypotaurine metabolism. The potential factors contributing to the effect of FF and basic commercial duck feed (CF) were found to be primarily regulated via the aforementioned metabolic pathways. The study, therefore, offers a viable approach for enhancing the taste and quality of duck meat.

Natural egg yolk emulsion as wall material to encapsulate DHA by two-stage homogenization: Emulsion stability, rheology analysis and powder properties.

The use of safe physical means to achieve egg yolk as natural carrier for active ingredients plays an important role in increasing the added value of egg yolk. In this paper, we prepared DHA-fortified egg yolk emulsion using high-speed shearing (HSS) only and HSS combined with high-pressure homogenization (HPH), respectively. HPH reduced particle size and zeta potential, allowing for better emulsion stability. After 14 days of storage, the encapsulation efficiency was 93.88% even with 15% (w/w) algae oil addition. Rheology analysis presented that HPH improve the viscoelasticity, indicating the enhancement of interaction force between droplets. Then, vaccum low-temperature spray drying (VLTSD) was used to produce powder, which allowed for minimal damage to the encapsulation structure according to scanning electron microscopy and the hydration properties of powder was improved. This work provides a new idea for using egg yolk to encapsulate DHA and improving the properties of egg yolk powder.

Colloidal Nanoparticles Isolated from Duck Soup Exhibit Antioxidant Effect on Macrophages and Enterocytes.

Food-derived colloidal nanoparticles (CNPs) have been found in many food cooking processes, and their specific effects on human health need to be further explored. Here, we report on the successful isolation of CNPs from duck soup. The hydrodynamic diameters of the obtained CNPs were 255.23 ± 12.77 nm, which comprised lipids (51.2%), protein (30.8%), and carbohydrates (7.9%). As indicated by the tests of free radical scavenging and ferric reducing capacities, the CNPs possessed remarkable antioxidant activity. Macrophages and enterocytes are essential for intestinal homeostasis. Therefore, RAW 264.7 and Caco-2 were applied to establish an oxidative stress model to investigate the antioxidant characteristics of the CNPs. The results showed that the CNPs from duck soup could be engulfed by these two cell lines, and could significantly alleviate 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH)-induced oxidative damage. It indicates that the intake of duck soup is beneficial for intestinal health. These data contribute to revealing the underlying functional mechanism of Chinese traditional duck soup and the development of food-derived functional components.

Effect of salt penetration and water migration on cooked salted egg yolk gel during storage: Physicochemical properties, structural characteristics and flavor changes.

There is an urgent need to explore the salt penetration and water migration in the cooked salted egg yolk (CSEY) gel. The aim of this study was to investigate the effect of salt and water on the physicochemical, structural and flavor characteristics of CSEY gel stored at 25 °C. The hardness of the yolk increased significantly (608.0 g â†’ 2730.7 g) during storage. The results of LF-NMR showed that the free water content in the yolk gel was enhanced. The microstructure of CSEY could be observed by SEM, which showed that during storage, polyhedral particles were dispersed due to the heating process. In addition, ethyl acetate (71.9 %) was completely undetectable in the CSEY-21 d. In summary, the sample at and before 14 d of storage had good processing value. Therefore, this work would provide theoretical guidance for the low-sodium pickling of SEY (salted egg yolk) and its suitable storage methods.

A basis for IgY-themed functional foods: Digestion profile of oral yolk immunoglobulin (IgY) by INFOGEST static digestion model.

Although yolk immunoglobulin (IgY) has been reported its functions of antiviral, antibacterial, energy balancing, and gut microbiota regulating, its gastrointestinal digestion process and the digestion products have not been studied, which is of great significance for the development of IgY-themed functional foods. This work investigated the digestion behaviors of oral IgY by static digestion simulation in vitro. IgY showed low digestibility (23.97%) in the gastric phase but was highly digestible (89.49% digestibility) in the initial intestinal phase. The entire digestion involved IgY aggregation, degradation, re-aggregation, and gradual decomposition into small pieces (by dynamic light scattering). These results indicated that IgY was impressionable, unstable and changeful in gastrointestinal environment, which might impair the bioactive function of IgY. Over 6 peptides (such as RGFK, TVPSGASTK, VPAATASPR) and 21 amino acids were detected, including 6 essential amino acids (methionine, isoleucine, leucine, histidine, tryptophan, and lysine), suggesting that IgY could be involved in human health regulation as active peptides or as rich sources of amino acids in addition to its own bioactive functions. The digestion kinetic curve confirmed that IgY did not reach its maximum digestion at the end of simulation of intestinal phase, implying the incomplete utilization of IgY. This study provides valuable details of oral IgY for development as active ingredients of a functional food, contributing to boosting the egg industry and improving human health.

Lysozyme impacts gel properties of egg white protein via electrostatic interactions, polarity differences, local pH regulation, or as a filler.

The effects of lysozyme on egg white gel properties and their underlying causes were investigated under comparison between lysozyme removed with ion exchange resin and three levels of commercial lysozyme powder (1/2, 2/2, 3/2 the natural concentration in egg white) re-added in the lysozyme-removed system. Results showed that a lysozyme-removed gel obtained the best water holding capacity (61.61 %), lowest cooking loss (11.85 %), and enhanced textural properties (hardness, 638.04 g; resilience, 0.57; and gumminess), which was attributed to lysozyme promoting protein aggregation and weakening electrostatic repulsion by charge neutralization and competition for water, and this could be eliminated by removing lysozyme. Besides, the stronger intermolecular interactions (enhanced ionic bonds, hydrogen bonds and inhibited hydrophobic interactions), the shorter transverse relaxation time (T21 and T22), as well as more uniform microstructure formed in the lysozyme-removed gel, allowing the gels to bind more water molecules. With return of lysozyme, the gel properties were weakened to varying degrees, which was also ascribed to the filling of lysozyme in gel matrix narrowed interspace for binding and storage of water. In sum, adjustment on the content of lysozyme can regulate the gel properties of egg white, so as to obtain gels with regulable gel quality and processing characteristics.

Immunomodulatory effects of chicken soups prepared with the native cage-free chickens and the commercial caged broilers.

The objective of this study was to compare the immunomodulatory effects of the chicken soups prepared with the native free-range chickens and the commercial caged broilers in the immunosuppressive mice. The immunosuppressive mice model was established by the intraperitoneal injection of 100 mg of cyclophosphamide (CTX) per kg body weight. The powders of Gushi Chicken Soup (GCS), Honglashan Chicken Soup (HCS), and Cobb Broiler Soup (CBS) were prepared by high-pressure stewing followed by spray drying. The chicken soups' nutrient content and the effects of three chicken soups on the body weight, organ index, blood index, and serum cytokine and immunoglobulin contents in the immunosuppressive mice were determined. The three chicken soups promoted the recovery of immunosuppressive mice, but the expression mechanisms were different. The GCS was more effective than the HCS and CBS in restoring blood index, promoting cytokine secretion, and increasing immunoglobulin content (P < 0.05). The HCS stimulated the Th1-type immune response and promoted immunoglobulin secretion (P < 0.05), while the CBS increased the production of CD4+ and promoted the T-cell functions better than other soups (P < 0.05). Although soups from the native free-range chickens and the commercial caged broilers showed distinctly different mechanisms in promoting immunity, both could be used as potential immunomodulators.

Encapsulation efficiency and oral delivery stability of chitosan-liposome-encapsulated immunoglobulin Y.

The degradation of acidic gastric juice on immunoglobulin Y (IgY) leads to destruction on the structural and loss of the bioactivity, limiting the bioavailability of oral IgY and its research or application in adjuvant treatment of diseases. In this work, it was surmounted with IgY-loaded chitosan-liposomes prepared by supercritical carbon dioxide-assisted method. A range of chitosan concentrations (0%, 0.5%, 0.8%, 1.1%, and 1.4%) were selected to explore the influence of chitosan concentration on the encapsulation effectiveness, stability, and in vitro-simulated digestive release properties of liposome-encapsulated IgY. The results displayed that owing to the robust interaction between chitosan and liposomes, the particle size, encapsulation efficiency, and stability of liposomes reached the optimal state at a chitosan concentration of 0.8%, with the encapsulation efficiency reaching 77.51%. Moreover, the liposomes could be stored at 4°C for 9 days without obvious sedimentation. The zeta potential of liposomes containing 0.8% chitosan was higher than that of samples without chitosan at high salt concentration treatment. In vitro release experiments demonstrated that liposomes fitted well in the Peppas equation. Chitosan-coated liposomes were capable of delaying the release of IgY in the stomach during simulated digestion, allowing more IgY to be released in the intestine. To sum up, Chitosan played a vital role in maintaining the stability and encapsulation of IgY, and the results of this work provide a theoretical basis for the development and utilization of chitosan and the protection of activity of IgY when administered orally. PRACTICAL APPLICATION: IgY serves as a bioactive substance with anti-inflammatory, antibacterial, and antioxidant functions. However, it is far from satisfactory for the oral delivery activity of IgY. Encapsulation of liposomes contributed to alleviate the release of IgY in the stomach. However, liposomes were less stable and not efficient enough to encapsulate IgY. This study demonstrated that the addition of 0.8% chitosan could effectively enhance the encapsulation efficiency of liposomes and improved the stability of liposomes. It might contribute to the solution of the oral delivery activity of IgY and provide a promising idea for the utilization of chitosan.

Improved effect of ultrasound-assisted enzymolysis on egg yolk powder: Structural properties, hydration properties and stability characteristics.

Preparation of egg yolk powder (EYP) with excellent hydration properties and dissolution stability is important for the efficient utilization of its functional properties and nutritional properties in food. In this work, a new method utilizing ultrasound-assisted enzymolysis (UP-EM) was investigated to obtain EYP. Compared to enzymolysis-alone treated (EM), ultrasonic pre-treatment (UP) significantly increased the enzymatic hydrolysis rate by 106.28%. In particular, the UP 60 W 20 min-EM group obtained the desired solubility and coefficient of stability. The observed microstructure of EYP showed that the egg yolk particles obtained by UP-EM were more uniformly distributed and smaller in particle size. The protein structure was confirmed by Fourier transform infrared spectrum, which showed that UP enhanced the hydrogen bonding force between egg yolk proteins. Therefore, it can be believed that UP-EM can significantly improve the hydration properties and dispersion stability of EYP, laying the foundation for its wide applications in food industry.

Formation of Natural Egg Yolk Granule Stabilized Pickering High Internal Phase Emulsions by Means of NaCl Ionic Strength and pH Change.

Pickering high internal phase emulsions (HIPEs) are gel-like concentrated emulsions that have the potential to be an alternative to partially hydrogenated oil (PHO). In this study, egg yolk granules (EYGs), natural complexes of protein and lipid isolated from egg yolk, were used as an emulsifier to prepare Pickering HIPEs. Gel-like HIPEs with an oil phase volume fraction of 85% and with an emulsifier concentration of only 0.5% could be prepared by using EYGs as an emulsifier. The EYGs were able to form stable HIPEs at NaCl ionic strengths over 0.2 M and at pH over 5.0 with NaCl ionic strength of 0.3 M. The EYGs, which could stabilize HIPEs, were easily to adsorb and cover the oil-water interface to form emulsion droplets with small particle size. In addition, interacting EYGs in the aqueous phase formed a continuous network structure, and the oil droplets packed closely, exhibiting high elasticity and shear thinning behavior. Furthermore, the formed HIPEs had suitable storage stability with no significant changes in appearance and microstructure after storage for 60 days. This work can transform traditional oils from liquid-like to solid-like by using EYGs to enrich food processing diversity and improve the storage stability of oils while reducing the intake of PHO and providing a healthier diet for consumers.

Effect of high intensity ultrasound assisted glycosylation on the gel properties of ovalbumin: Texture, rheology, water state and microstructure.

In this paper, the effects of ultrasonic assisted glycosylation on the gel properties of ovalbumin (OVA) were studied. The molecular characteristics of native ovalbumin, heated ovalbumin, traditional glycosylated ovalbumin, ultrasonic ovalbumin and ultrasonic assisted glycosylated ovalbumin were compared. The lowest free amino group content and the highest browning intensity indicated that ultrasonic can facilitate the Maillard reaction. The gel hardness of ultrasonic glycosylation and the traditional heating glycosylation groups individually increased to 653.2 and 526.9 g compared with the control (344.9 g). The transformation of protein structure was confirmed by FTIR and fluorescence spectrum, which prompted negatively charged groups to reach the protein surface and form more disulfide bond in sOVA-X gel. The interaction between the water and the protein was strengthened, thereby increasing the water holding capacity. These results supplied a theoretical basis for the application of ultrasonic to improve protein properties.

Intelligent colorimetric film incorporated with anthocyanins-loaded ovalbumin-propylene glycol alginate nanocomplexes as a stable pH indicator of monitoring pork freshness.

Protein-polysaccharide nanocomplexes system could improve the low stability of ACNs, making ACNs become a potential and stable pH indicator. In this study, intelligent colorimetric film was designed to monitor pork freshness by incorporating ACNs-loaded ovalbumin-propylene glycol alginate nanocomplexes (ACNs-loaded OVA-PGA) into polyvinyl alcohol/ glycerol (PG) matrix. The intelligent film (PG/ACNs-loaded OVA-PGA film) presented well barrier performance (lower water vapor permeability and light transmittance at 200-600 nm). Fourier transform infrared spectroscopy further confirmed the hydrogen bonds among film-forming components. Moreover, Scanning electron microscope and X-ray diffraction showed that ACNs-loaded OVA-PGA was uniformly distributed in film matrix but decreased the crystallinity of polyvinyl alcohol. PG/ACNs-loaded OVA-PGA film had distinguishable colorimetric response to pH 2.0-11.0 buffers and volatile ammonia. In the test, PG/ACNs-loaded OVA-PGA film displayed visible color alterations from purplish-red to dark-blue as pork freshness decreased, suggesting it can be used in intelligent packaging for real-time monitoring freshness of meat products.

Preparation and characterization of egg yolk immunoglobulin loaded chitosan-liposome assisted by supercritical carbon dioxide.

The egg yolk immunoglobulin (IgY) loaded chitosan-liposomes (IgY-CS-LP) were prepared and assisted by supercritical carbon dioxide (SCCO2). The effects of phospholipid type and SCCO2 pressure on particle size, zeta potential, encapsulation efficiency, structural properties and stabilities were investigated. The results showed that the liposomes prepared by egg yolk phosphatidylcholine (EPC) had better homogeneity and higher encapsulation rate than those by soybean phosphatidylcholine (SPC). With the increase in critical pressure, the particle size decreased dramatically and became more uniform. Under pressure of 20 MPa, it showed a preferable stability on IgY-CS-LP and superior encapsulation efficiency of IgY (76.85%). Besides, IgY could be wrapped in the phospholipid layer which has strong interaction with chitosan. The results suggested that chitosan liposome complex could form an effective carrier for IgY with method of SCCO2, which can solve the problem of IgY inactivation in vivo, so as to enhance human immunity and other effects.

Gel properties of heat-induced transparent hydrogels from ovalbumin by acylation modifications.

In this paper, the effects of acylation modification on the gel behavior of ovalbumin (OVA) under heating induction have been investigated. From the obtained results, the acylated OVA hydrogels exhibited superior gelation properties than the native OVA hydrogels (NOVA-G) in terms of light transmission, gel hardness, resilience and water holding capacity. SEM revealed acylation modifications effectively promoted the formation of uniform and dense network structure of OVA hydrogels. The main intermolecular forces of the acylation-modified OVA hydrogels were hydrophobic interactions and hydrogen bonding. FTIR showed that acylation modifications caused 26.2% decrease in α-helix and 59.2% increase in ß-sheet content compared to NOVA-G. Furthermore, in-vitro release experiments showed that the release rate of curcumin from acylated OVA hydrogels was significantly delayed. Moreover, the above results have shown that acylation modifications can be considered as an effective method to improve the gelation as well as drug release properties of protein hydrogels.

Positive response to surfactants on the interfacial behavior and aggregation stability of Fab fragments from yolk immunoglobulin.

The antigen binding fragment (Fab) is pepsin-digested product from egg yolk immunoglobulin (IgY), which shows lower immunogenicity and higher antibacterial activity. However, it limited the application of Fab due to the spontaneous adsorption and aggregation at the air-liquid interface. The present work is to investigate the effect of surfactants polysorbate 20 (PS20), poloxamer 188 (P188), and polyethylene glycol (PEG) on the aggregation stability of Fab of IgY. The results confirmed the positive role of surfactants in improving Fab stability. PS20 could effectively prevent the generation of Fab aggregates (DLS and light-obscuration analysis). It could also distinctly increase the internal hydrophobicity level, fortify the surface charge by altering the molecular conformational characteristics of Fab. The results of CLSM and surface tension demonstrated that P188 and PEG were co-adsorbed with Fab at the air-liquid interface and inhibited the formation of aggregation. PS20 competitively adsorbed in the gap between Fab molecules to inhibit the formation of aggregates. These findings would give an in-depth understanding of protein aggregation behavior influenced by surfactants and provide a theoretical basis for the development of functional food based on Fab active fragments.