Characterization of the structure and properties of the isolating interfacial layer of oil-water emulsions stabilized by soy hull polysaccharide: Effect of pH changes

All-natural polysaccharide and protein complex nanoparticles from Clitocybe squamulosa as unique Pickering stabilizers for oil-in-water emulsions

This study aimed to develop novel nanoparticles that can serve as an excellent oil-in-water (O/W) Pickering stabilizer. The polysaccharide-protein complex nanoparticles (PPCNs-20 and PPCNs-40) were prepared at different ultrasonication amplitudes (20 % and 40 %, respectively) from the polysaccharide-protein complexes (PPCs) which were extracted from the residue of Clitocybe squamulose. Compared with PPCs and PPCNs-20, the PPCNs-40 exhibited dispersed blade and rod shape, smaller average size, and larger zeta potential, which indicated significant potential in O/W Pickering emulsion stabilizers. Subsequently, PPCNs-40 stabilized Pickering emulsions were characterized at different concentrations, pHs, and oil phase contents. The average size, micromorphology, rheological properties, and storage stability of the emulsions were improved as the concentration of PPCNs-40, the ratio of the soybean oil phase and pH value increased. Pickering emulsions showed the best stability when the concentration of PPCNs-40 was 3 wt%, and the soybean oil fraction was 30 % under both neutral and alkaline conditions. The emulsions demonstrated shear thinning and gelation behavior. These findings have implications for the use of eco-friendly nanoparticles as stabilizers for Pickering emulsions and provide strategies for increasing the added value of C. squamulosa.

Encapsulation of grape seed oil in oil-in-water emulsion using multilayer technology: Investigation of physical stability, physicochemical and oxidative properties of emulsions under the influence of the number of layers

Many studies have shown that grape seed oil (GSO) is one of the vegetable fats that are plentiful in essential fatty acids and can be used as a fat substitute or to modify fat in food products to reduce saturated fatty acids. However, due to its low solubility and high sensitivity to oxidation, it is necessary to develop delivery systems that can distribute GSO in food more effectively. Recently, the preparation of emulsions using the layer-by-layer (LBL) method has many advantages in delivering lipid-soluble functional compounds. This research was used to check the formation of GSO oil-loaded primary, secondary and tertiary multilayer emulsions stabilized by mixture of anionic gelatin, cationic chitosan, and anionic basil seed gum (BSG) as the aqueous phase at pH 5, prepared using a layer-by-layer electrostatic deposition technique. Multilayer emulsions prepared by GSO and a mixture of gelatin, chitosan, and BSG as the aqueous phase at pH 5. Finally, the effect of the number of layers on the physicochemical properties (particle size, viscosity, turbidity, refractive index, and physical stability) and oxidative stability (peroxide value, thiobarbituric acid value, and fatty acid profile) during the storage time (30 days) at two temperatures 25 °C & 4 °C was investigated. Also, the zeta potential and Fourier transform infrared spectroscopy (FTIR) of mono-layer and multi-layer emulsions were investigated. The results revealed that by increasing the number of layers of multi-layer emulsion of GSO, the stability has improved. Thus, the tertiary emulsion has been more effective than the other two emulsions in maintaining the physicochemical characteristics and stability over time (P < 0.001). Morphological characterization and FTIR spectroscopy results confirmed that gelatin, chitosan, and BSG were successfully loaded into the LBL emulsions. This study can improve the original percept of multilayer emulsions and promulgate their potential applications for the entire encapsulation of essential fatty acids to enrich and prevent peroxide attack.

Spray-drying and rehydration on β-carotene encapsulated Pickering emulsion with chitosan and seaweed polyphenol

The spray-drying process to generate microcapsules from Pickering emulsions needs high temperatures, leading to instability of emulsions and degradation of encapsulated thermosensitive compounds (β-carotene). However, these effects may be attenuated by the introduction of seaweed polyphenols into the emulsion interfacial layers, although the effects underlying this protective mechanism have not been explored. This study evaluates the effects of spray-drying/rehydration on the morphology, encapsulation efficiency, redispersibility, and stability of β-carotene loaded Pickering emulsions stabilized by chitosan (PESC) and Pickering emulsions stabilized by chitosan/seaweed polyphenols (PESCSP). The encapsulation efficiency of β-carotene in PESCSP microcapsules (61.13 %) was higher than PESC (53.91 %). Rehydrated PESCSP exhibited more regular droplet size distribution, higher stability, stronger 3D network morphology, and lower redispersibility index (1.5) compared to rehydrated PESC. Analyses of interfacial layers of emulsions revealed that chitosan covalently bound fatty acids at their hydrophobic side. Polyphenols were linked to chitosan at the hydrophilic side of emulsions through hydrogen bonds, providing 3D network between droplets and antioxidant activities to inhibit the degradation of β-carotene. This study emphasized the role of polyphenols in the interfacial layers of Pickering emulsions for the development of efficient delivery systems and protection of β-carotene and other thermosensitive bioactive compounds during spray-drying and rehydration.

Preparation and characterization of aspirin-fucoidan complex and its admirable antitumor activity on human non-small cell lung cancer cells

The purpose of this work is to prepare a novel acetylated derivative of Undaria pinnatifida fucoidan (UPFUC) with admirable antitumor activity. Fucoidan was first acetylated by acetylsalicylic acid (aspirin, ASA) to form the ASA-UPFUC complex. The antitumor efficacy results stated that ASA-UPFUC inhibited the proliferation of human non-small cell lung cancer A549 cells in a dose-dependent manner, with an IC50 value of 49.09 μg/mL, 50.20 % lower than that of UPFUC. Importantly, the acetylation process had no adverse effects on the backbone structure of UPFUC. Simultaneously, ASA-UPFUC demonstrated a larger charge density than UPFUC, leading to enhanced solubility, improved surface charge effects, and a greater potential for exerting biological activity. Consequently, ASA-UPFUC increased the formation of alkyl and hydrogen bonds with tumor necrosis factor related apoptosis-inducing ligand receptors DR4 and DR5, thereby effectively stimulating the generation of cellular reactive oxygen species, diminishing mitochondrial membrane potential, suppressing nuclear factor κB (NFκB) p65 phosphorylation, enhancing the contents of Bax and cleaved caspase 3, and reducing the level of Bcl-2. The collective effects ultimately triggered the mitochondrial apoptotic pathway, leading to apoptosis in A549 cells. The findings support the potential utilization of ASA-UPFUC as a novel dietary additive for human lung cancer chemoprevention.

Acid-induced conformation regulation of peanut polysaccharide and its effect on stability and digestibility of oil-in-water emulsion

BACKGROUND

Developing the stable and healthy emulsion-based food is in accord with the needs of people for health. In the present study, acidification at pH 3.0 of peanut polysaccharide (APPSI) was employed to regulate its conformation and further improve its advantages in preparing oil-in-water emulsion.

RESULTS

The results indicated that acidification induced conversion of PPSI aggregates into linear chains. Increasing concentration promoted formation of cross-linked network structure shown in transmission electron microscopy images. Consequently, the viscosity, yield stress, storage modulus and flow activation energy significantly increased, further fabricating gel structure. Moreover, aggregation behavior suggested that more exposed proteins were involved in gel structure, thereby forming many hydrophobic cores as verified by fluorescence spectroscopy of pyrene. Afterwards, emulsion characteristics indicated that APPSI produced strong and thick steric hindrance around oil droplets and the coil-like interweaved chains locked the continuous phase, bringing strong elasticity and resistance to stress and creaming. Meanwhile, the lower fatty acid in APPSI-emulsion was released after simulated gastrointestinal digestion, mainly as a result of the high retention ratio of emulsion droplets. Furthermore, the elastic and viscous Lissajous curves suggested that the structure strength of APPSI-emulsion was similar to that of the salad dressing within the strain 53.22%.

CONCLUSION

The conformation of PPSI after acidification at pH 3.0 was suitable for preparing the stable emulsion. The obtained emulsion could resist digestion and maintain a strong structure, comprising a cholesterol-free and low-fat salad dressing substitute. © 2023 Society of Chemical Industry.

Effect of polysaccharide concentration on heat-induced Tremella fuciformis polysaccharide-soy protein isolation gels: Gel properties and interactions

The formation of a single soybean protein isolate (SPI) gel is limited by the processing conditions, and has the disadvantages of poor gel property, and it is usually necessary to add other biomacromolecules to improve its property. In this study, we investigated the effects of polysaccharide concentration on gel properties and interaction mechanisms of Tremella fuciformis polysaccharide (TFP)-SPI complexes. It was found that (1) the rheological properties, texture properties, water-holding properties, and thermal stability of TFP-SPI composite gels were improved with the addition of TFP (0.25-2.0 %, w/v) in a concentration-dependent manner; (2) hydrogen bond, the electrostatic interaction, hydrophobic interaction, and disulfide bond in the gel system increased with the increase of TFP concentration; (3) the electrostatic and hydrophobic interactions played an important role in the formation of the TFP-SPI composite gel while hydrogen bond formation was the least contributor to the binary composite gel network. Overall, TFP is not only a critical health food but also a promising structural component for improving the gel properties of SPI.

Migration of Nutrient Substances and Characteristic Changes of Chicken White Soup Emulsion from Chicken Skeleton during Cooking

The protein and fat in chicken skeleton can be emulsified in a boiling state to form milky white chicken soup. White chicken soup has a delicious taste, good nutritional value, a beautiful color, and volatile flavor compounds. However, cooking time significantly impacts the quality of white chicken soup. Herein, we investigated the influence of cooking time (30, 60, 90, 120, 150, 180, and 210 min) on the migration of nutrient substances and characteristics changes in white chicken soup from chicken skeletons. The results showed that nutrients such as total lipids, water-soluble protein, total sugars, solid matter, and oligopeptides in the chicken skeletons' tissue continuously migrated into the soup during the cooking process. The total nutrient content in the chicken soup was highest after cooking for 180 min. Simultaneously, the white chicken soup obtained after cooking for 180 min had low interfacial tension and high whiteness, viscosity, and storage stability. The high stability index was associated with increased ζ potential and decreased particle size. The contact angle analysis results also indicated that the stability of the white chicken soup was improved when the cooking time reached 180 min. This research provides basic information for the production of high-quality white chicken soup.

Improvement in texture and color of soy protein isolate gel containing capsorubin and carotenoid emulsions following microwave heating

The effects of microwave heating on the properties and pigment release of soybean protein isolate (SPI) emulsion gel and hydrogel were investigated. The properties of the samples were analyzed by rheology and texture. The results showed that the hardness of the emulsion gel was lower than that of the hydrogel, but the cohesiveness was the opposite. The hydrogen bonding and electrostatic interaction between SPI and soybean soluble polysaccharide (SSPS) enhanced the thermal stability of the gel, and the enthalpy values were the lowest. In addition, a chroma meter was used to assess the slow-release effect of pigment, with results indicating that the emulsion gel was more red and yellow than the hydrogel; the values of a* and b* were reduced with the extension of heating time, indicating that the emulsion had a good protective effect on carotenoids and capsorubin, which was helpful to the application of the pigment in food.

Inherent molecular characteristics and effect of garlic polysaccharides on dough micro- and mesoscopic properties

Directional control of the process of doughs with nutrition fortification is challenging. Thus, this study aimed to develop non-starch polysaccharides that can modify the quality of flour products. Polysaccharides were extracted from three different garlic cultivars, evaluated for physicochemical properties and used to enrich doughs for microstructure and mesoscopic characteristics analysis. We assessed the moisture distribution, texture characteristics, thermodynamic properties, dynamic viscoelastic properties, protein structure, microstructure and molecular interaction of the doughs and demonstrated a relatively high molecular weight, lower steric hindrance of molecular chains and higher cross-linking ability with the dough network in the supernatant polysaccharide from Yunnan single-clove-garlic (SGSOS) fraction. These features of SGSOS fraction improved the rheological, thermodynamic, texture characteristics, and water distribution of doughs. These findings provide information on the use of garlic polysaccharides during the processing and manufacturing of foods to enhance their processing adaptability and qualities.

Inonotus obliquus polysaccharide are linear molecules that alter the abundance and composition of intestinal microbiota in Sprague Dawley rats

Introduction

The macromolecular polysaccharide Inonotus obliquus polysaccharide (IOP) is composed of various monosaccharides, and it could modulate the composition and diversity of intestinal flora. However, its impact on the intestinal flora in rats of different genders remains unclear. Therefore, this study aims to investigate the structural changes of IOP and its effects on the intestinal flora after administration in male and female rats.

Methods

In this study, the molecular weight and purity of IOP were analyzed by high-performance gel permeation chromatography (HPGPC) and phenol sulfuric acid method, and NMR was used to confirm the chemical structure of IOP. Sex hormone [testosterone (T) and estradiol (E2)] levels and intestinal microbial changes were detected by enzyme-linked immunosorbent assay (ELISA) and 16S rRNA, respectively, after gavage of IOP (100 mg/kg) in male and female Sprague Dawley (SD) rats.

Results

HPGPC analysis showed that the average molecular weight (Mw) of IOP was 4,828  Da, and the total sugar content of the purified IOP was 96.2%, indicating that the polysaccharide is of high purity. NMR revealed that IOP is a linear macromolecule with an α-D-type glucose backbone. The results of ELISA and 16S rRNA showed that the IOP increased the abundance of beneficial bacteria, such as Clostridia_UCG-014 and Prevotellaceae_NK3B31, and reduced that of harmful bacteria, such as Colidextribacter and Desulfobacterota in the intestine of both male and female rats, and IOP changed the levels of sex hormones in male and female rats. Further analyses revealed that the increase in alpha diversity was higher in male than female rats. α diversity and β diversity revealed a significant difference in the composition of cecal microbiota between male and female rats in the control group, but IOP intake reduced this difference. Meanwhile, α analysis revealed a change in the composition of bacterial flora was more stable in male than female rats.

Conclusions

This study enhances our comprehension of the IOP structure and elucidates the alterations in intestinal flora following IOP administration in rats of varying genders. Nonetheless, further investigation is warranted to explore the specific underlying reasons for these discrepancies.

Tremella fuciform Polysaccharides: Extraction, Physicochemical, and Emulsion Properties at Different pHs

The chemical composition, macromolecular characteristics, and structure of four types of Tremella fuciform polysaccharides (TPS) were analyzed, including one TPS that was extracted in the laboratory (L-TPS) and three commercial TPS. The effects of pH on the properties of TPS emulsions were investigated by analyzing their zeta potential, particle size, apparent viscosity, and stability. The results showed that L-TPS presented a higher percentage content of protein (2.33%) than commercial TPS (0.73–0.87%), and a lower molecular mass (17.54 × 106 g/mol). Thus, L-TPS exhibited the best emulsifying activity but gave poor emulsion stability. The droplet sizes and apparent viscosity of commercial TPS-stabilized emulsions were larger or higher in acidic environments. At pH 2, the apparent viscosity was the lowest for L-TPS. Commercial TPS emulsions were most stable at pH 6, while the L-TPS-stabilized emulsion was most stable at pH 2. The obtained results revealed that the emulsifying properties of TPS varied and the effects of pH on emulsion characteristics differed, as determined from the molecular mass, macromolecular characteristics, and structure. This research is useful for expanding the application of TPS as a novel food ingredient in emulsions.

Storage stability and interfacial rheology analysis of high-internal-phase emulsions stabilized by soy hull polysaccharide

High-internal-phase emulsions (HIPEs) are more promising candidates for development to replace hydrogenated fatty acids, yet the current HIPEs are limited for stabilizers require very high surface activity. This study showed that HIPEs could be prepared with 1.0-2.2 wt% soy hull polysaccharide (SHP) and the related stability indicators of HIPEs were analyzed. The plasticity, stress resistance, stability of the HIPEs were positively correlated with the SHP content. The interfacial adsorption experiments showed that SHP had the good ability to reduce interfacial tension and formed an elastic interfacial layer. Dilatational rheological results showed the interfacial film reached jammed saturation at about 1.8 wt% of SHP concentration, and the zeta potential results were consistent. This study demonstrated that SHP was an efficient stabilizer of HIPEs, which was useful both for the preparation of HIPEs and for developing uses for SHP.

Effects of environmental stimuli on the physicochemical and rheological properties of chitosan-macroalgal polyphenol stabilized Pickering emulsion

In this study, Pickering emulsions stabilized by chitosan (CS), chitosan-Laminaria japonica polyphenols (CP) and chitosan-Ascophyllum nodosum polyphenols (CB) were fabricated. This study also evaluated the stability of CS, CP, and CB under different environmental factors including pH (2-9), NaCl concentrations (0-500 mM), heat treatments (50-100 °C) and storage period (0-8 weeks). The characterization on interfacial layer of emulsion droplets demonstrated that macroalgal polyphenols could combined with the amorphous regions of chitosan particles through hydrogen bond and electrostatic interactions, providing stronger dual wettability with enhanced ability of interfacial layer in stabilizing Pickering emulsions. All three emulsions showed best droplet distribution, highest emulsion stability and specific surface area at pH 6 and 0 mM NaCl concentration as fresh emulsion. Moreover, CS, CP, and CB exhibited the rheological behaviour of pseudoplastic fluids at different pH and NaCl concentration. It should be noted that CP and CB exhibited higher emulsion stability than CS under a variety of environmental stresses. Overall, this research proved that chitosan-macroalgal polyphenol co-stabilized Pickering emulsion had enhanced stability against various environmental stimuli, which could be utilized as potential delivery and protection system for hydrophobic bioactive compounds.

Fabrication and Characterization of Botanical-Based Double-Layered Emulsion: Protection of DHA and Astaxanthin Based on Interface Remodeling

Both DHA and astaxanthin, with multiple conjugated double bonds, are considered as health-promoting molecules. However, their utilizations into food systems are restricted due to their poor water solubility and high oxidizability, plus their certain off-smell. In this study, the interactions between perilla protein isolate (PPI) and flaxseed gum (FG) were firstly investigated using multiple spectroscopies, suggesting that hydrophobic, electrostatic force and hydrogen bonds played important roles. Additionally, double-layer emulsion was constructed by layer-by-layer deposition technology and exhibited preferable effects on masking the fishy smell of algae oil. Calcium ions also showed an improving effect on the elasticity modulus of O/W emulsions and was managed to significantly protect the stability of co-delivered astaxanthin and DHA, without additional antioxidants during storage for 21 days. The vegan system produced in this study may, therefore, be suitable for effective delivery of both ω-3 fatty acid and carotenoids for their further incorporation into food systems, such as plant-based yoghourt, etc.

Gel-type emulsified muscle products: Mechanisms, affecting factors, and applications

The gel-type emulsified muscle products improve fatty acid composition, maintain the oxidative stability, and achieve a better sensory acceptability. This review emphasizes the stabilization mechanisms of these emulsified muscle products. In particular, factors associated with the stability of the emulsified muscle systems are outlined, including the processing conditions (pH and heating), lipids, and emulsifiers. Besides, some novel systems are further introduced, including the Pickering emulsions and organogels, due to their great potential in stabilizing emulsified gels. Moreover, the promising prospects of emulsion muscle products such as improved gel properties, oxidative stability, freeze-thaw stability, fat replacement, and nutraceutical encapsulation were elaborated. This review comprehensively illustrates the considerations on developing gel-type emulsified products and provides inspiration for the rational design of emulsified muscle formulations with both oxidatively stable and organoleptically acceptable performance.

Effects of different enzyme extraction methods on the properties and prebiotic activity of soybean hull polysaccharides

In this study, five different processes, including hot water (HW-ASP), single enzyme (cellulase, pectinase and papain; C-ASP, PE-ASP, and P-ASP), and compound-enzyme (cellulose: pectinase: papain = 3:3:1; CE-ASP) for the extraction of soybean hull polysaccharides (ASPs) were employed, and the characterization and prebiotics activity of five polysaccharides were analyzed. These polysaccharides possessed different primary structural characteristics, including molecular weight distribution, monosaccharide composition, chemical composition, surface morphology, potential particle size, etc., while similar functional groups. In vitro digestibility assay indicated that C-ASP had strong resistance to gastric juice hydrolysis and α-amylase as compared with HW-ASP. Furthermore, C-ASP elevated the acidifying activity and promoted the growth of probiotics (Lactobacillus paracasei, Lactobacillus rhamnosus, and Lactobacillus acidophilus) during the fermentation (p < 0.05). C-ASP improved the levels of total short-chain fatty acids (SCFAs) and had better prebiotic activity than HW-ASP (p < 0.05). These findings denote that enzyme-assisted polysaccharides extracted from soybean hulls have the potential to be served as novel probiotics.

High intensity ultrasound-assisted quality enhancing of the marinated egg: Gel properties and in vitro digestion analysis

In this study, high intensity ultrasonication (HIU) was employed as an efficient tool to improve the gel property and in vitro digestibility of marinated egg (ME). The effects of HIU treatment at 100 W and 200 W for a series of time periods (0.5 h, 1 h, and 2 h) on the textural profiles, structural changes, and microstructures were also studied. After HIU treatment, the springiness and gumminess of ME white were enhanced. The water holding capacity reached the highest point (66.6%) when 0.5 h 200 W HIU was used. It was observed that 100 W HIU led to the highest zeta potential (-12.0 mV) and hydrophobicity (175.35 μg) of ME, indicating a high degree of electrostatic repulsion prevented agglomeration. HIU treatment at 100 W affected the dynamic rheological behaviors by boosting non-covalent bonds, which maintains the gel network's homogeneity. Meanwhile, the decreasing formation of α-helix, in contrast to β-turn, altered the aggregation behaviors of egg white gel. The microstructure of the 200 W HIU treated samples had porous colloidal network structures, and the in vitro digestibility (>75%) was increased after HIU. This work demonstrated that HIU could be a green and cost-effective tool for processing the egg product with high quality.