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Despite the potential benefits of using cellulose ethers and their combination with other polysaccharides and proteins in the creation of reduced-fat water-in-oil (W/O) emulsions, research in this specific area is currently limited. Further studies are needed to explore the optimal combinations and concentrations of these materials to achieve emulsions with desired texture and higher rheological properties. To address this research gap, seven W/O emulsions with a 40 wt% water phase at pH 3.5 are prepared. The water phase consisted of 2 wt% methylcellulose (MC) or hydroxypropyl methylcellulose (HPMC) combined with 10 wt% whey protein isolate (WPI) and/or kappa-carrageenan (kC). The oil phase, comprising 60 wt%, contained 8 wt% polyglycerol polyricinoleate (PGPR) in soybean oil. The emulsions were initially prepared at room temperature and subsequently subjected to a heating process at an elevated temperature of 90 °C for a duration of 30 min. Following this heating step, the emulsions were then cooled back to room temperature. This sequential temperature treatment was employed with the intention of inducing aggregation and gelation within the emulsions. The temperature oscillation measurements (G* versus temperature) provide further evidence for the role of covalent and noncovalent bonding in the rheology and gelation of WPI-based emulsions. The viscosity and moduli of unheated and heated emulsions containing combinations of HPMC were found to be higher compared to those containing MC combinations. This behavior can be attributed to the stronger intermolecular interaction between HPMC, WPI, and/or kC, as well as their attachment with PGPR. These interactions lead to the formation of a more viscous and firmer W–O interface in emulsions. [Display omitted] • W/O emulsions prepared using cellulose ethers, WPI, and/or kappa carrageenan aggregation in the aqueous phase. • They exhibit high viscosity and elasticity and form compact microstructures when undergoing heat treatment. • HPMC combinations showed higher rheological properties compared to the equivalent MC emulsions. [ABSTRACT FROM AUTHOR]

Abstract The rheological behavior of gels prepared from albumin (ALB) and a mixture of ALB and low methoxyl amidated pectin (PEC) with different proportions were studied using oscillatory rheological tests, Fourier transform infrared spectroscopy (FT-IR spectroscopy), zeta potential measurements and confocal microscopy. The mixture was always 5% of the total solute. Assays were performed in two series, one in which all mixtures were adjusted to pH = 8 and another one without pH adjustment. The zeta potential values indicated the presence of a negative net charge on ALB-PEC gels. The rheological tests indicated a frequency dependence of the storage (G′) and loss (G") moduli, with G' > G". The presence of 1% and 2% of pectin in the mixture caused an increase in G'. However, a PEC concentration above 2% led to a decrease in G′, regardless of the pH or frequency. FT-IR spectroscopy indicated that as the PEC content increased, a higher proportion of β-sheet structures was found. Confocal microscopy also confirmed aggregation of ALB particles due to the PEC concentration. Highlights • The interactions between the pectin and albumin have electrostatic feature. • Gels from albumin and pectin are weak regardless of pH. • The increase of G′ was associated with the synergism between the albumin and pectin. • The addition of pectin above the critical concentration led to a decrease in G'. [ABSTRACT FROM AUTHOR]

Abstract Bambara groundnut is a protein-rich legume of African origin. This study investigated the influence of fractionation pH on degree of complexation of bambara protein isolate (BPI) with gum arabic (GA). BPI extracted at pH 2, pH 7, pH 9 and by the traditional salt solubilisation method were complexed with GA. BPI-GA complexes appeared as spherical particles (average size: 100–200 nm) that were aggregated. Optimal pHs of biopolymer interactions decreased (pH opt : 4.8 to 2.9) as protein extraction pH became more acidic. pH 2 fraction had the lowest coacervates yield (41%). ζ-potential profiles of protein fractions displayed similar pH dependent patterns, but with different pHs of net neutrality. The pH 2 fraction showed a high molecular weight protein (100 kDa), which was absent in other fractions. It also contained the highest content of basic amino acids. Protein extraction pH could be manipulated to produce better acid-stable structures on complexation with polysaccharides. Graphical abstract Image Highlights • Extraction pH significantly affected the degree of protein complexation with gum arabic. • Bambara protein –gum arabic coacervates appeared as spherical structures (100–200 nm). • High content of basic amino acids in protein fractions seems to lower coacervates yields. • PH opt of biopolymer interactions decreased as protein extraction pH become more acidic. [ABSTRACT FROM AUTHOR]

Casein and soy soluble polysaccharide formed compacted complex aggregates in pH 3–4.5 aqueous solutions by electrostatic and hydrophobic interactions. The diameters of the complex aggregates were about 133 nm. The oil in water emulsion produced from the complex at pH 4 was stable after 500 days of storage in pH 2–6.8 media at 4 °C due to the compacted complex interfacial film. The curcumin loading efficiency of the emulsion was 99.9% and diameter of the droplets was about 324 nm. Only 3% of the loaded curcumin degraded when the emulsion was stored at 4 °C for 40 days. About 73% of the curcumin was released after 2 h digestion of the emulsion in simulated gastric fluid followed by 2 h digestion in simulated intestinal fluid. The curcumin pharmacokinetics in mice was analyzed after oral administration. The curcumin absorption of the emulsion treatment group was more rapid and effective than the absorption of curcumin/Tween 20 suspension treatment group. The curcumin oral bioavailability of the emulsion group was 11-fold higher than the bioavailability of curcumin/Tween 20 suspension group. This study demonstrated that casein and soy polysaccharide complex emulsion is an applicable system for oral delivery of lipophilic nutrients and drugs. [ABSTRACT FROM AUTHOR]

Food-grade polymers such as proteins and polysaccharides have attracted great interest in recent years as excellent stabilisers for emulsion gels due to their good biocompatibility, environmental friendliness, and low cost. The obtained emulsion gels with specific properties can be used as extrudable inks in 3D printing. To further understand the application of food-grade polymers in emulsion gels construction, the interaction between proteins and polysaccharides as well as their mechanisms of stabilizing emulsion gels were reviewed. Besides, the feasibility of applying emulsion gels to 3D printing systems is discussed. Finally, this paper provides a brief outlook on using 3D-printed emulsion gels as practical foods. Proteins after the physical, chemical, and enzyme modifications are allowed to obtain emulsion gels by emulsion filling and particle aggregation. The mechanism of polysaccharide-based emulsion gels construction can be mainly distinguished as single stabilizing, bulk gelling, polysaccharide complexion stabilizing and dual-layer stabilizing, respectively. When used together, proteins and polysaccharides mainly stabilize emulsion gels by polysaccharide thickening, multilayer wrapping, or complex stabilizing. The emulsion gels with properties of shear-thinning, smooth flowability, and powerful stability can be successfully used as 3D printing inks. This review gathers and analyses mechanisms of applying food-grade polymers like proteins and polysaccharides to stabilize emulsion gels and summarizes the feasibility of emulsion gel application for 3D printing. This work can provide basic guidance for the development and application of low-fat and healthy fat-substitutes. [Display omitted] • Modifications of proteins for preparing emulsion gels are reviewed. • Polysaccharides used for emulsion gel stabilization are summarized. • Extrudability, flowability and stability are keys to emulsion gel 3D printing. • The limitations and prospects of emulsion gel 3D printing are discussed. [ABSTRACT FROM AUTHOR]

A comparative study of both the bulk and air/liquid interfacial rheological responses was carried out by using four kinds of representative high molecular weight and highly branched polysaccharide emulsifiers, (a) corn fiber gum (CFG), (b) octenyl succinate anhydride-modified starch (OSA-s), (c) gum arabic (GA) and (d) soybean soluble polysaccharides (SSPS), spanning the concentration range of 1–15 wt%. We found that the bulk and interfacial rheological properties of their aqueous solutions were significantly different. While both CFG and OSA-s showed Newtonian flow behavior at higher concentrations, both GA and SSPS exhibited obviously shear thinning behavior or thixotropy even at a low concentration of 1 wt%. The time-dependent flow behavior for CFG, GA and SSPS reflected microstructural breakdown and rebuilding in solutions under shear, indicated that their proteinaceous portion was strongly bound to their polysaccharide part. This phenomenon was not observed for the almost protein-free OSA-s. The interfacial rheology responses showed that the layers formed by CFG and OSA-s were viscously predominant with faster formation kinetics while they were elastically predominant for GA and SSPS with slower formation kinetics. Interfacial viscoelastic responses of CFG and OSA-s were weaker than those of GA and SSPS. By comparison, the interfacial layer for OSA-s showed pure viscous responses whereas SSPS showed the highest elastic responses. These significant disparities in bulk and interfacial viscoelasticity of the four polysaccharide emulsifiers reflect the influence of different fine chain structures on the dissimilarity in the intermolecular associations and the architectures of the interfacial layers. [ABSTRACT FROM AUTHOR]

Fining treatment is an important step in winemaking but its mechanism is still not well known. To have a better understanding of the protein fining process, the influence of polysaccharides and glycerol, major compounds in wine, on proanthocyanidin precipitation was studied. A wine and a model wine obtained from its polyphenol fraction were analyzed before and after fining by a gelatin and a plant protein, a hydrolyzed gluten HG. The results showed that polysaccharides and glycerol modify quantitatively proanthocyanidin precipitation, but not much the nature of the precipitated proanthocyanidins. The nature of the remaining proanthocyanidins in the treated model wines after protein fining was not much modified neither. All proanthocyanidins were not recovered after the fining treatments when polysaccharides and glycerol were added to the model wines. These results suggested the creation of soluble complexes between proanthocyanidins, fining proteins and polysaccharides. The efficiency of the fining treatment could be thus modified by the content of the wines. [ABSTRACT FROM AUTHOR]

The electrostatic interactions between cationized gelatin (CG) and gum arabic (GA) have been investigated through turbidity measurements and dynamic light scattering. Gelatin was modified with ethylenediamine (EA) to introduce additional primary amino groups to enhance polycationic nature needed for complexation with polyanionic gum arabic. This study aims to gain an insight into the interactions of gelatin with GA after modification with EA. The interaction between these polyelectrolytes (GA and CG) has been studied by varying different parameters. Nanosized CG/GA complex was formed by the simple mixing of CG (0.1%, w/v) and GA (0.1%, w/v) with mixing ratio 1:1 (v/v). The effect of pH on the CG/GA complex nanoparticles (1:1, v/v) was examined by measuring changes in turbidity, hydrodynamic size and zeta potential. By varying the mixing ratio of the corresponding polymers, different types of CG/GA complex (clear and turbid) could be prepared. This study provides information regarding the effect of pH, ionic strength and biopolymer mixing ratio on the formation of polyelectrolyte complexes of cationized gelatin and gum arabic. [ABSTRACT FROM AUTHOR]

Introduction There is great interest in converting gluten, a by-product from wheat starch isolation, into a value added functional food ingredient. Earlier, gliadin nanoparticles were produced using liquid antisolvent precipitation, but they did not prove to be very stable in conditions relevant to food products. Materials and methods Gliadin nanoparticles were produced by antisolvent precipitation: a gliadin in ethanol solution was titrated into water. After production, the nanoparticles (0.5 w/v% protein) were coated with different polysaccharides: octenyl succinic anhydride (OSA) starch; low methoxyl pectin (LMP); or, high methoxyl pectin (HMP). Results and discussion At all concentrations used (0.001 – 0.20 w/v%), OSA-starch led to particle flocculation and precipitation, whereas both LMP and HMP were able to coat the particles without inducing flocculation at certain levels (0.10 w/v%). The mean particle size of pectin-coated particles was about double that of uncoated ones, and the charge reversed from positive (uncoated) to negative (coated) under mildly acidic conditions. The pectin coating was shown to improve the stability of the gliadin nanoparticles to environmental stresses, such as pH, ionic strength, and thermal treatment. Conclusions Coating gliadin nanoparticles with pectin may therefore be a useful means of forming stable functional ingredients for use in the food industry, e.g., as texture modifiers, lightening agents, or delivery systems. [ABSTRACT FROM AUTHOR]

Abstract: Aqueous mixtures of small aggregates of the globular whey protein (β-lactoglobulin) and the anionic polysaccharide (κ-carrageenan) were studied at neutral pH. The effect of the temperature on the phase separation was investigated by measuring the turbidity during cooling and heating. Gelation of κ-carrageenan was induced by adding small quantities of KCl. It is shown that gelation partially reverts phase separation. The dependence of phase separation on the elastic modulus was quantified. Phase separation could be rendered irreversible by ageing in the presence of calcium ions. [Copyright &y& Elsevier]

Abstract: The microstructure of oil droplets of bi-layer emulsions was studied as a function of pH (i.e. 7, 5, and 3) using scanning electron microscopy. The bi-layer emulsions consisted of a primary emulsion: 5 wt% soybean oil (SBO) in a 1% protein (nonfat dry milk) aqueous solution. The secondary layer was ι-carrageenan, high- (HMp), low (LMp)-methoxyl pectin, or gelatin. The secondary emulsions consisted of 2.5% SBO, 0.5% protein, and 0.2% polysaccharide or protein. Gelatin secondary emulsions were stable at pH 7 with defined droplets and became unstable at pH 5 and 3. The destabilization mechanisms for these emulsions at pH 5 and 3 were different as observed with the SEM: at pH 5 there is complete aggregation of protein due to their proximity to the isoelectric point; and at pH 3 the droplets are perfectly separated, suggesting that at this pH, when the net charge is positive, the destabilization is mainly due to depletion flocculation. HMp secondary emulsions shift from being stable (individual droplets) at pH 3 to being unstable at pH 7 where an extensive webbing is observed between the droplets at this pH value. The ι-carrageenan secondary emulsions are stable at each pH and the individual droplet microstructure is minimally altered as the pH changes. LMp secondary emulsions shift from being stable at pH 7 with individual droplets observed in the SEM micrographs to being unstable at pH 3 where extensive webbing is observed in the SEM micrographs. [Copyright &y& Elsevier]

Abstract: Soybean soluble polysaccharide (SSPS), extracted from the by-product obtained during isolation of soybean protein, is an anionic polysaccharide that stabilizes milk proteins under acidic conditions. We developed a high-molecular-mass complex of SSPS cross-linked via phosphate (SSPS-HC; absolute molecular weight = 2850 kg/mol, radius of gyration = 106 nm), and found that it has different protein stabilization properties when compared with the original SSPS (absolute molecular weight = 550 kg/mol, radius of gyration = 36 nm). The objective of this work was not only to study the rheological properties of SSPS-HC, but also clarify its protein-stabilizing properties in comparison with SSPS; if molecular mass or negative charge affected protein dispersion. Irrespective of high-molecular-mass, SSPS-HC possessed similar rheological properties to SSPS such as low viscosity in aqueous solution. The absolute negative charges of SSPS-HC measured by a zeta potential analyzer at pH range of 2.0–7.0 were higher than those of SSPS. Acidified milk drinks prepared with 8.4% non-fat milk solids and 0.4% SSPS-HC or SSPS showed low viscosity and small protein particle size, and did not aggregate for 14 days. The thickness of the hydrated layer, which was formed on the surface of protein particles by SSPS molecules measured after hemicellulase treatment with DLS (dynamic light scattering), was estimated to be about 89 nm for SSPS-HC and 33 nm for SSPS. These numerical values were in good relation to the molecular diameter of SSPS-HC and SSPS in aqueous solution measured by DLS and AFM image, and suggested that protein particles were dispersed and the hydrated monolayer made on the surface of protein particles by SSPS-HC or SSPS molecules prevented aggregation. However, stabilizing pH ranges were different with stability of SSPS-HC at pH range of 4.0–4.8 and stability for SSPS at pH range of 3.6–4.2. In addition to the difference in the molecular mass and absolute negative charge, the phosphate groups of SSPS-HC were possibly influenced on the protein-dispersing property approximately at isoelectric point of milk protein; SSPS-HC prevent aggregation of casein by accelerating solubility of calcium phosphate under acidic conditions as is already reported in the starches phosphorylated. [Copyright &y& Elsevier]

Abstract: The stability of oil-in-water, water-in-water and multiple emulsions containing sodium caseinate (Na-CN) and/or locust bean gum (LBG) at pH 5.5 was investigated with different compositions using a visual analysis (creaming and/or phase separation), optical microscopy and rheological measurements. Oil-in-water emulsions (O/W) were produced by high pressure homogenization, which promoted the formation of very small droplets (∼0.4μm) and hindered the destabilization process. In the second step of this study, a visual phase diagram was constructed in order to identify the concentrations of sodium caseinate (Na-CN) and locust bean gum (LBG) that led to phase separation at pH 5.5. A mixed solution composed of 3% (w/v) Na-CN and 0.3% (w/v) LBG was chosen to produce the water-in-water and multiple emulsions. After centrifugation, the solution was separated into an upper phase rich in polysaccharide (PS) and a bottom phase rich in protein (PR), which were mixed in different proportions (1:3, 1:1, 3:1), forming the water-in-water (W/W) emulsions. The stability, microstructure and rheological properties of the W/W emulsions depended strongly on the composition of the biopolymers. An increase in the polysaccharide concentration in the W/W emulsions led to the production of more viscous and stable systems. Multiple emulsions with different characteristics were prepared and also depended on the biopolymer composition. The system with the highest polysaccharide content was the only one that showed an O/W/W structure, while the others presented the microstructure of an O/W-W/W emulsion. [Copyright &y& Elsevier]

Abstract: Protein–polysaccharide interactions find many applications in food engineering and new food formulations. This review article describes recent research on the effect of protein–polysaccharide interactions on the properties of air–water and oil–water interfaces, as affected by their behaviour in the bulk phase. The interfacial behaviour of protein–polysaccharide mixtures exhibiting associative (i.e., net attractive) interactions as well as their performance in food emulsions and foams has been the subject of several reviews in the last decade. Much less attention has been paid to the interfacial behaviour of protein–polysaccharide mixtures exhibiting unfavourable interactions. Thus we are concerned here with the interfacial behaviour of both kinds of mixtures. [Copyright &y& Elsevier]

Abstract: A new technique for the purification of pectins using protein (sodium caseinate) was developed and that could replace the process of ethanol which is currently used in industries. Commercial pectins were used as a model to verify the feasibility of the process and to define some important parameters. The results indicated that this purification technique is based primarily on the electrostatic interactions between these two polymers. The electrostatic interactions were strongly dependent on pH and salt concentration. The maximum pectin precipitation was obtained at pH 3.5. At this pH, the pectin acquires a negative charge while the protein is positively charged, promoting thus their attractions. Furthermore, the dissociation of the pectin–caseinates complex and the precipitation of caseinate at pH 4.6 were observed in the presence of salt. This method is very specific, suggesting that it could be used to purify some electrically charged polysaccharides. [Copyright &y& Elsevier]

Abstract: Gelation of sodium κ-carrageenan (KC) in the presence of sodium caseinate (SC) was investigated by oscillating shear rheology. The effect of adding NaCl and KCl was investigated. Temperature ramps showed that SC had no influence on the critical gelation temperature, but increased the melting temperature when that of the pure gels was less than about 30 °C. The presence of SC also increased the gel strength of weak KC gels. Light scattering and confocal laser scanning microscopy showed that the proteins associated with the KC network. The rheology of the gels indicated that the mixed gels contained bonds involving both SC and KC in addition to pure KC bonds. At relatively high SC content the former type of bonds dominated. [Copyright &y& Elsevier]

Abstract: Mixtures of the polysaccharide κ-carrageenan (KC) and caseinate proteins (SC) from milk were investigated at pH 7 in aqueous solution using confocal scanning laser microscopy and light scattering. Phase separation was observed at higher concentrations and the phase diagram was established. In the mixtures SC was observed to form large aggregates mediated by a relatively small amount of KC. At small KC concentrations the aggregates were initially relatively small and could be characterized by light scattering. At higher KC concentrations or on longer storage at 20°C, dense clusters with a radius of a few microns were formed that slowly precipitated. The fraction of precipitated protein increased linearly with increasing KC concentration, but was independent of the protein concentration. It increased with decreasing pH from about 20% at pH 8 to 100% at pH 5. [Copyright &y& Elsevier]

Abstract: The objective of the work was to study the effect of limited hydrolysis of soy protein on the interactions with polysaccharides with and without surface activity at the air–water interface at neutral pH where a limited incompatibility between macromolecules can occur. The surface pressure and phase angle as a function of time were evaluated with a drop tensiometer at 20°C, pH 7 and ionic strength 0.05M. Hydrolysates of 2% (H1) and 5.4% (H2) degree of hydrolysis (DH) with neutral protease from Aspergillus oryzae were obtained from a commercial soy protein isolate. The polysaccharides used were: hydroxypropylmethylcellulose (HPMC) as surface active polysaccharide; lambda carrageenan (λC) and locust bean gum (LB) as non-surface active polysaccharides. It was found that increasing DH decreased the surface pressure and increased film viscoelasticity (determined as the phase angle, θ) of soy protein hydrolysates and the nature of protein–polysaccharide interactions was strongly affected by DH. The presence of polysaccharides led to an increase of surface pressure of H1 but when added to H2, HPMC and λC decreased the surface pressure. The less hydrolyzed protein H1 gave rise to a higher surface pressure and film viscoelasticity in combination with the polysaccharides. This result points out that a limited protein hydrolysis was sufficient to improve the surface properties of soy proteins if used in combination with polysaccharides. Polysaccharides used in admixture with hydrolyzed soy proteins could control and improve the stability of foams and emulsions not only by increasing bulk viscosity but also by improving film viscoelasticity. [Copyright &y& Elsevier]

Abstract: Foods systems containing polysaccharides and proteins tend to be structurally heterogeneous due to polymer incompatibility and phase separation, at least on a microscopic scale. This study was designed to determine the effect of such phase separation on the bulk glass transition temperature of frozen solutions containing sucrose, lactose, milk salts, protein from skim milk powder and guar or locust bean gum. The glass transition temperature of sugar-containing solutions was increased by the presence of polymer (protein or polysaccharide). However, the bulk glass transition temperature of microscopically phase-separated systems was dominated by the protein phase, suggesting that theoretical determinations of complex systems based solely on composition may fail to accurately predict glass transition temperatures, due to component structural heterogeneity. It was also shown that there was a difference in the amount of glass that formed within each domain, due to differential concentrations of the phase-separated polymer and its effect on dilution of the sugars in true solution. This may also affect predicted glass transition temperatures. [Copyright &y& Elsevier]

Abstract: The objective of the work was to study the effect of different non-surface active polysaccharides on the foaming properties of intact and hydrolysed sunflower protein isolate (SP) (degree of hydrolysis of 1.5 and 9.8%) at neutral pH where a limited incompatibility between macromolecules can occur. Foams were obtained by whipping and the overrun, liquid drainage and collapse of the height of foams were evaluated. A limited enzymatic treatment substantially enhanced foaming properties of sunflower protein. A small degree of hydrolysis (DH=1.5%) enhanced both foam overrun and foam stability against liquid drainage and collapse. However, an increase of DH to 9.8% did not further improve foaming properties. The overrun of foams was decreased in the presence of all the polysaccharides but the performance of polysaccharides as stabilizers of foams depended on the protein hydrolysis, the structure of the polysaccharide and its concentration in the liquid used to make the foam. Xanthan gum at 0.25 and 0.5%, due to its high viscosity performed as stabilizer of both intact and hydrolysed SP foams. The other polysaccharides at 0.25% performed as stabilizers when added to the intact SP foams but destabilized the foams containing the hydrolysed SP. By increasing PS concentration, the detrimental effect could be partially reverted. The results may be interpreted in terms of the bulk and surface rheological properties of the mixed protein/polysaccharide foams and suggest that protein–polysaccharide interactions are strongly affected by the hydrolysis of the protein. [Copyright &y& Elsevier]

In the present work we have studied the adsorption (dynamic surface pressure) of β-lactoglobulin (βLG), polysaccharides and their mixtures at the air–water interface at 20°C and at pH 7. The measurements were performed on a automatic drop tensiometer. As polysaccharides with interfacial activity we have used propylene glycol alginates (PGA). To evaluate the effect of the degree of PGA esterification and viscosity, different commercial samples were studied—Kelcoloid O (KO), Kelcoloid LVF (KLVF) and Manucol ester (MAN). Xanthan gum (XG) and λ-carrageenan (λ-C) were studied as non-surface active polysaccharides. The results reveal a significant effect of surface-active and non-surface-active polysaccharides on dynamic characteristics of β-lactoglobulin adsorbed films. To explain the observed effects on the rates of diffusion, penetration, and rearrangement of these biopolymers at the air–water interface, three phenomena were taken into account: (i) the competitive adsorption; (ii) the complexation, and (iii) the existence of a limited thermodynamic compatibility between protein and polysaccharide at the air–water interface and in the bulk aqueous phase. Surface-active polysaccharides (MAN, KO) are less effective than non-adsorbing polysaccharides (XG) for increasing the surface pressure of protein films, because a competitive behaviour with protein. Highly hydrophilic polysaccharides that do not adsorb by their own at the interface (XG, λ-C) or surface-active polysaccharides with low hydrophobicity (KLVF) show a cooperative behaviour with protein that promotes a significant increase of surface pressure of adsorbed films. [Copyright &y& Elsevier]

In the present work we have studied the static (film structure and elasticity) and dynamic characteristics (surface dilatational properties) of β-lactoglobulin (βLG) monolayers spread at the air–water interface in the presence of polysaccharides in the aqueous phase, at 20 °C and at pH 7. The measurements were performed on a fully automated Wilhelmy-type film balance. As polysaccharides with interfacial activity we have used propylene glycol alginates (PGA). To evaluate the effect of the degree of PGA esterification and viscosity, different commercial samples were studied-kelcoloid O (KO), kelcoloid LVF (KLVF) and manucol ester (MAN). Xanthan gum (XG) and λ-carrageenan (λC) were studied as non-surface active polysaccharides. The results reveal a significant effect of surface active and non-surface active polysaccharides on static—when the polysaccharide was added in the subphase the π-A isotherms shifted to higher surface pressure values as the time increased-and dynamic—the presence of polysaccharide in the aqueous phase decreased the surface dilatational modulus of a pure β-lactoglobulin monolayer-characteristics of β-lactoglobulin monolayers. To explain the observed effects three phenomena were taken into account: (i) the ability of the polysaccharide to adsorb at the interface by it-self and to increase the surface pressure, (ii) the interfacial complexation of the polysaccharide with the adsorbed protein and (iii) the existence of a limited thermodynamic compatibility between the protein and polysaccharide, depending on the protein-polysaccharide system. [Copyright &y& Elsevier]

Solid fats provide desirable functionality, texture, and palatability to foods; however, they are related to adverse chronic health effects. Consumers and regulatory authorities are demanding more natural and healthy ingredients. Thus, in context of the high demand for healthy foods and the transition to more sustainable ingredients, oil structuring emerges as an outstanding strategy to substitute saturated and trans fats. Researchers have developed optimised indirect routes to structure oil with hydrocolloids resulting in gelled emulsions and oleogels. Novel healthy food structures based on polysaccharides, proteins, and their supramolecular interactions are suitable to create several types of healthy colloidal systems with unique sensory, texture, and stability properties. [Display omitted] • Oil structuring is an effective technology to replace solid saturated and trans fats. • Hydrocolloid-based oleogelation can be achieved through indirect methods. • Fundamental insights of oleogelation using protein and polysaccharides are discussed. • Research trends in hydrocolloid-based oleogels and gelled emulsions are evaluated. [ABSTRACT FROM AUTHOR]

The extraction conditions of a water-soluble lentil polysaccharide fraction (SLPS) from lentil fibers were examined. The effect of temperature, pH, and time of extraction was evaluated, to determine optimal conditions resulting in a high yield of high molecular mass polysaccharides. The optimal extraction temperature and time combination was 120 °C for 90 min. Under these conditions, the yield was as high as 23.3% at pH 4 and 19.6% at pH 8. Further, two different extractions were carried out, both for 90 min at 120 °C, one at pH 4 (SLPS4) and the second at pH 8 (SLPS8), and the fractions characterized for composition and molecular mass. The weight average molecular mass (Mw) of the main component in the fraction was 830 kg/mol for SLPS4 and 1130 kg/mol for SLPS8. Albeit SLPS4 and SLPS8 showed the same sugar linkages, their composition was different: SLPS4 contained, glucose 52.7%, arabinose 27.6%, and galacturonic acid 6.0%, whereas SLPS8 contained arabinose 49.8%, glucose 19.1%, and galacturonic acid 13.2%. The polysaccharides were observed by a scanning probe microscope and showed a characteristic multi-branched structure, with sugar chains extending from the center to the periphery of the molecule. Both SLPSs were used as stabilizers in an acidified milk system, containing 3% (w/w) non-fat milk solids. At a concentration of 0.4% (w/w) both SLPS4 and SLPS8 were able to maintain a mono-modal distribution of fine particles in the range of pH between 3.6–4.4 or 3.8–4.4, for SLPS4 and SLPS8, respectively. This work demonstrates the potential for the creation of a value added ingredient from lentil polysaccharide. [Display omitted] • Extraction conditions of lentil polysaccharide from lentil fibers were examined. • The weight average molecular mass of lentil polysaccharide differed in extraction pH. • Lentil polysaccharide molecule observed by SPM showed a multi-branched structure. • Lentil polysaccharide dispersed protein particles in the range from pH 3.6 to 4.4. [ABSTRACT FROM AUTHOR]