Quillaja Saponin Research Articles

Bioaccessibility and stability of β-carotene encapsulated in plant-based emulsions: impact of emulsifier type and tannic acid.

The effect of two plant-based emulsifiers (quillaja saponin, QS and gum arabic, GA) and a polyphenol (tannic acid) on the formation, stability, digestibility, and β-carotene (BC) bioaccessibility of flaxseed oil-in-water emulsions was investigated. The gastrointestinal behavior of the emulsions was studied using a simulated gastrointestinal tract (GIT) consisting of mouth, stomach, and small intestine regions. In the absence of tannic acid, the initial extent of lipid digestion depended strongly on emulsifier type, with 45% and 76% of the free fatty acids being released after 5 min digestion for QS- and GA-emulsions, respectively. Even so, the lipid droplets were completely digested in both emulsions after 2 h incubation in the small intestine phase. Tannic acid addition (0.01% and 0.1% w/w) slowed down lipid digestion, but did not impact the final extent. The droplets in the QS-emulsions containing 0.1% tannic acid were highly flocculated in the stomach phase. Molecular docking simulations indicated that the interactions between tannic acid and the saponins were mainly driven by hydrogen bonding and hydrophobic interactions. Moreover, they showed that the interactions between tannic acid and QS were stronger at pH 2.5 than at pH 7.0, which would account for the extensive droplet flocculation observed under acidic conditions in the stomach. Emulsifier type and tannic acid addition had no significant influence on BC bioaccessibility. The GA-emulsions exhibited better stability than the QS-emulsions when stored at elevated temperatures (55 °C for 7 days). Tannic acid addition effectively inhibited temperature-induced BC degradation. These results may facilitate the design of more efficacious nutraceutical-loaded functional foods and beverages.

Emulsion-based control of flavor release profiles: Impact of oil droplet characteristics on garlic aroma release during simulated cooking

The objective of this research was to elucidate the main factors influencing flavor retention in oil-in-water emulsions during simulated cooking, including oil droplet concentration, oil type, droplet size, and emulsifier type. Allyl methyl disulfide (AMDS), a hydrophobic flavor in garlic that is easily lost from foods during processing, storage, and preparation, was used as a model aroma compound. The impact of droplet characteristics on the flavor retention profile of AMDS-loaded emulsions subjected to simulated cooking conditions was determined, which involved heating from them from room temperature to boiling and then holding them for 30 min. The flavor retention half-time (FT1/2) was calculated from the retention-time curves, i.e., the time for the flavor concentration to decrease to half its initial value. Based on FT1/2, the flavor retention during cooking depended on oil type: palm oil > corn oil > mineral oil. However, the mineral oil emulsions were also the most unstable to droplet coalescence during cooking. Increasing the oil droplet concentration in the emulsions increased flavor retention during cooking, but also decreased their physical stability. Based on FT1/2, the type of emulsifier used to formulate the emulsions also influenced flavor retention: quillaja saponin > Tween 80 > sodium caseinate > whey protein isolate. The emulsions that were most unstable to coalescence during cooking, and therefore had the largest droplet sizes, tended to have better flavor retention (longer FT1/2). The observed differences in flavor retention were mainly attributed to differences in the size and location of the oil droplets during cooking. These results have important implications for the design of food matrices that can control flavor retention and release during food preparation.

Food-Grade Saponin Extract as an Emulsifier and Immunostimulant in Emulsion-Based Subunit Vaccine for Pigs.

Subunit vaccines consisting of highly purified antigens require the presence of adjuvants to create effective and long-lasting protective immunity. Advances on adjuvant research include designing combination adjuvants which incorporate two or more adjuvants to enhance vaccine efficacy. Previously, an oil-in-water emulsion adjuvant (OW-14) composed of mineral oil and an inexpensive gum Arabic emulsifier has been reported demonstrating enhanced and robust immune responses when used as an adjuvant in swine subunit vaccines. This study presents a modified version of OW-14 prepared with food-grade Quillaja saponin extract (OWq). In new OWq emulsion, saponin extract served as an emulsifier for stabilization of emulsion droplets and as an immunoactive compound. The use of saponins allowed to reduce the required amount of emulsifier in the original OW-14. However, emulsion stabilized with saponins demonstrated extended physical stability even at elevated temperature (37°C). The two-dose vaccination with a classical swine fever virus (CSFV) glycoprotein E2-based vaccine formulated with OWq produced higher levels of E2-specific IgG and virus neutralizing antibodies in pigs in contrast with animals that received the vaccine adjuvanted with oil only. In addition, new OWq adjuvant was safe to use in the vaccination of pigs.

Ozonized water with plant antimicrobials: An effective method to inactivate Salmonella enterica on iceberg lettuce in the produce wash water

Post-harvest washing of produce is performed to remove physical debris and to lower microbial load. The use of ozone in combination with plant-based antimicrobials was evaluated as an alternative to conventional sanitizers such as chlorine. Plant based antimicrobials that were evaluated in combination with ozone included oregano oil, carvacrol, Quillaja saponin and olive extract. Ozone was dispersed in phosphate buffered saline (PBS), following which individual antimicrobials or their combinations were added. Iceberg lettuce leaves (10 g portions) inoculated with Salmonella enterica serotype Newport (6.5 ± 1 log CFU/g) were added to the wash suspension. The leaves were tested for reduction in S. Newport population after 60, 90 and 120 min of treatment. Exposure to ozonized water for 120 min resulted in a 2.1 log CFU/g (p < 0.05) reduction in S. Newport population. The addition of 0.1% oregano oil to ozonized water resulted in 3 log CFU/g reduction after 120 min but a 4.1 log CFU/g reduction after 60 min, indicating that the antioxidant property of oregano oil might have diminished ozone activity and resuscitated injured S. Newport cells. The addition of 5% olive extract to ozonized water resulted in 4.2 log CFU/g reduction of S. Newport after 120 min (p < 0.05) of treatment. While 5% olive extract did not confer protection to S. Newport cells from ozone, 1% olive extract resulted in higher S. Newport survival after 120 min treatment than the 60 min treatment. The use of carvacrol (0.1%, 0.3% and 0.5%) in ozonized water reduced the pathogen population to below the limit of detection (10 CFU/g) (p < 0.05) which was in excess of 6 log CFU/g. These results indicate that the efficacy of ozone is compounded by the addition of certain plant-based antimicrobials when used at optimum concentrations. Ozone combined with plant antimicrobials could serve as an effective alternative to sanitizers currently used for washing and processing of produce.

Enhancing the formation and stability of emulsions using mixed natural emulsifiers: Hydrolyzed rice glutelin and quillaja saponin

Emulsifiers can often be used in combination to improve their functional performance. In this study, we examined the potential of combining two natural emulsifiers, hydrolyzed rice glutelin (HRG) and quillaja saponin (QS), on the formation and stability of oil-in-water emulsions. In particular, we investigated the impact of total emulsifier level, QS-to-HRG ratio, pH, ionic strength, and temperature on the mean particle diameter (d3,2), ξ-potential, creaming stability, and microstructure of the emulsions. The size of the oil droplets produced by homogenization decreased as the QS-to-HRG ratio increased from 1:4 to 1:1, but remained constant after that. The ξ-potential and dimensions of the droplets coated by the mixed emulsifiers were reasonably similar to those coated by QS alone, suggesting that the adsorbed saponins dominated the interfacial properties in the mixed systems. We also determined the physical stability of emulsions prepared using HRG, QS, or 1:1 QS-HRG after exposure to pH changes (pH 3–7), salt addition (0–500 mM NaCl, pH 7) and thermal treatment (30–90 °C 30 min, 200 mM NaCl, pH 7). QS-emulsions were stable to aggregation and creaming over a wider pH range than the other emulsions. Conversely, the mixed emulsions had better stability to high salt levels and temperatures (pH 7), which was attributed to a thicker interfacial layer causing stronger steric repulsion. This research may increase the utilization of plant-based emulsifiers in food and beverage applications.

Influence of concentration ratio on emulsifying properties of Quillaja saponin - protein or lecithin mixed systems

The concentration ratio of binary surfactant systems can alter the interfacial layer properties, and consequently affect emulsion stability. To study the effect of varying concentration ratios (r, % w/w) of interfaces containing Quillaja saponins and other naturally occurring food-grade surfactants on their emulsifying properties, we evaluated particle size, ζ-potential, and appearance of 10% oil-in-water emulsions (pH 7) stabilized by Quillaja saponin - protein or Quillaja saponin - lecithin mixtures. Quillaja saponin - Na-caseinate mixtures (r = 0.3:0.2, 0.2:0.3, and 0.1:0.4) formed small emulsion droplets (d43: 0.2 – 0.3 μm), whereas at r = 0.4:0.1, the emulsions contained micron-sized droplets (d43: 1.217 ± 0.558 μm). Emulsions formed by Quillaja saponin - pea protein mixtures flocculated at r = 0.3:2.0, 0.2:3.0, and 0.1:4.0. In contrast, Quillaja saponin - rapeseed lecithin or egg lecithin mixtures were able to generate small emulsion droplets (d43: 0.2 – 0.5 μm) at all tested concentration ratios. The formation of stable emulsions using binary mixtures of naturally occurring emulsifiers was more dependent on the concentration ratio of the proteins than lecithins, indicating that the interfacial behavior of Quillaja saponins is more sensitive to the presence of proteins. This was attributed to attractive molecular interactions yielding complexes at interfaces and/or in the continuous phase. This study shows that food-grade binary surfactant mixtures can be used to form stable emulsions with properties being tunable by altering the mixing ratios between surfactants.

Influence of spray drying on the stability of food-grade solid lipid nanoparticles

This study investigated spray drying of food-grade solid lipid particles (SLN) and nanostructured lipid carriers (NLC) containing ω-3 fish oil. Stable SLN and NLC dispersions with tristearin as carrier lipid were formed by using a combination of Quillaja saponins and high-melting lecithin as emulsifiers. Our specific goal was to study the influence of four different spray drying inlet and outlet temperatures (Tinlet/outlet = 140–170 °C/65–95 °C) and two different maltodextrin types (DE 6 and DE 21) with different molecular weights as protective wall materials on the physical and polymorphic stability of the solid lipid particles. The results revealed that the low molecular weight maltodextrin DE 21 was a superior wall material in stabilizing the solid lipid particles. Moreover, the lipid particles spray dried at Tinlet/outlet of 140/65 °C exhibited the highest physical and polymorphic stability, whereas using higher Tinlet/outlet led to bigger particles which were more prone to polymorphic transition. This was also verified in a 71-day storage test. The findings were explained that by preventing the melting of the tristearin carrier lipid during spray drying, the crystallized lipid particles remained intact inside the amorphous maltodextrin layer and exhibited high physical and polymorphic stability. These findings are important for generating stable food-grade spray dried powders.

Comparison of natural and synthetic surfactants at forming and stabilizing nanoemulsions: Tea saponin, Quillaja saponin, and Tween 80

HypothesisThis study compared the interfacial and emulsification properties of tea saponins, quillaja saponins, and Tween 80. We hypothesized that tea saponins are an effective and sustainable source of plant-based emulsifiers that could replace synthetic or animal-based emulsifiers in many commercial applications. ExperimentsInterfacial tension measurements were used to characterize the behavior of the three surfactants at an oil-water interface. The emulsifying properties of the surfactants were determined by preparing oil-in-water emulsions containing 10 wt% medium chain triglycerides (MCT) and varying surfactant levels (0.1–2 wt%) using high-pressure homogenization (pH 7). The impact of surfactant type on emulsion formation and stability was determined by measuring particle size, zeta–potential, microstructure, and creaming stability. FindingsThe tea saponins were capable of producing nano-scale droplets (d32 < 200 nm) at low surfactant-to-oil ratios (SOR < 0.1). Emulsions containing tea saponins remained stable to droplet aggregation when exposed to various temperatures (30–90 °C), salt levels (0–200 mM NaCl), and pH values (3–9). However, droplet flocculation and/or coalescence occurred under highly acidic (pH 2) and high ionic strength (300–500 mM NaCl) conditions. Tea saponin-coated oil droplets appeared to be mainly stabilized by a combination of electrostatic and steric repulsion. The tea saponins behaved similarly or better than the other two emulsifiers under most conditions. These results suggest that tea saponins are effective plant-based surfactants that may have applications in commercial products.

Olive mill wastewaters decontamination based on organo-nano-clay composites

Green composites for environmental applications were successfully prepared by intercalation of the biosurfactant Quillaja saponin onto montmorillonite mineral clay on varying pH and surfactant/clay ratio. Equilibrium adsorption isotherms were constructed and the system was characterized by performing TGA and XRD analyses.The efficiency of the surfactant-modified clay in the removal of the organic content present in olive mill wastewaters (OMW) was evaluated by means of spectrophotometric measurements. The interest for this cogent issue comes from the consideration that, despite their high pollutant content, OMW can be considered as a potential resource of several organic compounds which can be recovered for a wide array of pharmaceutical and industrial applications. Two different strategies were proposed. In the first one, dried surfactant/clay hybrids were added to the batch samples under continuous stirring, while in the second alternative approach the organoclays were packed in chromatography column filled with multiple alternate layers of sand and organoclay.These studies revealed the efficacy of the methods used and suggested that the modification of the montmorillonite clay substrate significantly improves the performance of the clay.

Saponin Adsorption at the Air-Water Interface-Neutron Reflectivity and Surface Tension Study.

Saponins are a large group of glycosides present in many plant species. They exhibit high surface activity, which arises from a hydrophobic scaffold of triterpenoid or steroid groups and attached hydrophilic saccharide chains. The diversity of molecular structures, present in various plants, gives rise to a rich variety of physicochemical properties and biological activity and results in a wide range of applications in foods, cosmetics, medicine, and several other industrial sectors. Saponin surface activity is a key property in such applications and here the adsorption of three triterpenoid saponins, escin, tea saponins, and Quillaja saponin, is studied at the air-water interface by neutron reflectivity and surface tension. All these saponins form adsorption layers with very high surface visco-elasticity. The structure of the adsorbed layers has been determined from the neutron reflectivity data and is related to the molecular structure of the saponins. The results indicate that the structure of the saturated adsorption layers is governed by densely packed hydrophilic saccharide groups. The tight molecular packing and the strong hydrogen bonds between the neighboring saccharide groups are the main reasons for the unusual rheological properties of the saponin adsorption layers.

Fabrication ofOriganum compactumessential oil nanoemulsions stabilized using Quillaja Saponin biosurfactant

There is an increased interest for essential oil nanoemulsions as natural food preservatives. We utilized sugar-based surfactants including Quillaja Saponin (QS), Sucrose Monopalmitate (SMP), and Octyl Modified Starch (OMS). The outcomes presented that nanoemulsions could be successfully formed. Whereas oregano emulsions stabilized by SMP exposed to salt and acidic pH were highly unstable, QS could form more stable colloidal systems. Oregano nanoemulsions containing a very low amount of sunflower oil (SO) were not susceptible to Ostwald ripening during 60 days of storage at 20 degrees C. The optimization of the production process through response surface methodology revealed that incorporation of only 6.9 wt % SO at a microfluidization pressure of 73.5 MPa was sufficient to form a long-term stable nanoemulsion with no changes in antibacterial activity. This work gives valuable and practical information to produce a natural antimicrobial agent potentially applicable in food and beverage, as well as cosmetics and pharmaceutical industries. Practical applicationsRecently, there has been a great demand by not only food consumers but also manufacturers for products containing natural ingredients. In this study, a promising nanoemulsion delivery system for oregano as an essential oil model with long-term stability using a biosurfactant (Quillaja Saponin) was successfully produced by microfluidization. We optimized the formulation in terms of energy requirement and costs, which are important factors from an industry point of view. The fabricated colloidal dispersions have antimicrobial as well as flavoring and potential antioxidant applications in different products including food and beverages, as well as pharmaceutical and beauty products.

Stability of curcumin in oil-in-water emulsions: Impact of emulsifier type and concentration on chemical degradation

Oral ingestion of curcumin is claimed to be effective against several diseases, including inflammation and cancer. However, its utilization in food, supplement, and pharmaceutical products is often challenging due to its poor water solubility, high chemical instability, and limited oral bioavailability. Emulsion-based delivery systems can be designed to overcome these challenges, but their composition and structure must be optimized to ensure they function appropriately. This study examined the impact of emulsifier type on the formation and stability of curcumin-loaded oil-in-water emulsions: sodium caseinate; Tween 80; quillaja saponin; gum arabic. The effectiveness of these food-grade emulsifiers at forming emulsions by microfluidization was characterized in terms of their surface load, i.e., the mass of emulsifier per unit surface area. The surface loads decreased in the following order: gum arabic (55.3 mg/m2) > > saponins (2.0 mg/m2) > Tween 80 (1.6 mg/m2) > caseinate (1.5 mg/m2), which indicated that much more gum arabic was required to form emulsions than the other emulsifiers. Curcumin-loaded emulsions were then prepared under conditions where there was just enough emulsifier to cover the droplet surfaces (“critical”), and under conditions where there was an excess of emulsifier in the aqueous phase (“excess”). Initially, both critical and excess emulsions were physically stable and had similar appearances. In all emulsions, curcumin degradation during storage occurred more rapidly at pH 7 than at pH 3, and was faster at 55 °C than at 37 °C. The physical and chemical stability of the curcumin-loaded emulsions also depended on emulsifier type. After storage at 55 °C for 15 days, the extent of curcumin degradation decreased in the following order: saponins > > gum arabic ≈ casinate ≈ Tween 80. Moreover, droplet creaming was observed in the critical Tween 80 and saponin emulsions, but not in the other emulsions. These results suggest that saponin accelerated curcumin degradation, possibly due to its ability to promote peroxidation reactions. Emulsifier concentration did not significantly affect curcumin degradation. These results suggest that the physical and chemical stability of curcumin-loaded emulsions is influenced by emulsifier type and level. This information may be useful for formulating emulsion-based delivery systems for curcumin with improved physicochemical and functional properties.

Fabrication and characterization of quercetin loaded almond gum-shellac nanoparticles prepared by antisolvent precipitation

A novel nanoparticle (NP) delivery system was designed for encapsulation of bioactive compounds for which quercetin was used as a model. A combination of almond gum (AG) and shellac as biopolymers using the antisolvent method was employed to fabricate the NPs. The influence of several significant preparation factors was investigated. Bare shellac particles showed extreme aggregation when exposed to pH 1.2 (gastric acid conditions), whereas the colloidal system containing 0.7% AG was capable to form NPs with particle size of 197nm with no sign of physio-chemical instability at pH 1.2 and with an encapsulation efficiency (EE) of 78%. Addition of small amounts of polysorbate 80 and Quillaja Saponin led to a drastic decrease in particle size to 90 and 116nm, respectively, with an encapsulation efficiency higher than 98%. The morphology characterization of the NPs with Cryo-SEM revealed that most NPs were spherical with rough surfaces, indicating that AG adsorbed onto the shellac surface as was also reflected by electrokineic measurements. DSC and FTIR analyses indicated that inclusion of quercetin within the NPs coincided with a transition from the crystalline to the amorphous state.To conclude, this study presented the formulation of promising nanocarriers applicable not only in the food but also in the pharmaceutical industry.

Thymol nanoemulsion exhibits potential antibacterial activity against bacterial pustule disease and growth promotory effect on soybean

An antibacterial and plant growth promoting nanoemulsion was formulated using thymol, an essential oil component of plant and Quillaja saponin, a glycoside surfactant of Quillaja tree. The emulsion was prepared by a sonication method. Fifty minutes of sonication delivered a long term stable thymol nanoemulsion which was characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), cryogenic-field emission scanning electron microscopy (Cryo-FESEM) and fourier transform infra-red (FTIR) spectroscopy. Creaming index, pH and dilution stability were also studied for deliberation of its practical applications. The nanoemulsion (0.01–0.06%, v/v) showed substantial in vitro growth inhibition of Xanthomonas axonopodis pv. glycine of soybean (6.7-0.0 log CFU/ml). In pot experiments, seed treatment and foliar application of the nanoemulsion (0.03–0.06%, v/v) significantly lowered the disease severity (DS) (33.3–3.3%) and increased percent efficacy of disease control (PEDC) (54.9–95.4%) of bacterial pustule in soybean caused by X. axonopodis pv. glycine. Subsequently, significant enhancements of plant growth were also recorded in plants treated with thymol nanoemulsion. This is the first report of a thymol based nanoemulsion obtained using Quillaja saponin as a surfactant. Our study claims that nano scale thymol could be a potential antimicrobial and plant growth promoting agent for agriculture.

Natural antimicrobial delivery systems: Formulation, antimicrobial activity, and mechanism of action of quillaja saponin-stabilized carvacrol nanoemulsions

The objective of this research was to develop antimicrobial nanoemulsions using quillaja saponin as a natural surfactant, carvacrol as an antimicrobial agent, and medium chain triglyceride (MCT) oil as a ripening inhibitor. Oil-in-water antimicrobial nanoemulsions were fabricated by homogenizing 10 wt% oil phase (carvacrol and MCT) with 90 wt% aqueous phase (quillaja saponin in 5 mM sodium citrate buffer, pH 3.5). The physical stability and antimicrobial activity of these systems was compared to nanoemulsions formed using a synthetic non-ionic surfactant (Tween 80). Stable nanoemulsions with small mean droplet diameters (d < 150 nm) could be formed by optimizing oil phase composition and surfactant level. The antimicrobial activity of carvacrol nanoemulsions formulated with Q-Naturale® was higher than that formulated with Tween 80. Dialysis and chromatography were used to monitor the transfer of carvacrol from one hydrophobic phase to another, to mimic transport from oil droplets to bacterial cell membranes. The antimicrobial activity depended on the concentration and type of surfactant used and the ability of surfactant micelles to transfer carvacrol through the aqueous phase.

Stabilization and Rheology of Concentrated Emulsions Using the Natural Emulsifiers Quillaja Saponins and Rhamnolipids.

Concentrated emulsions are widely used in the cosmetic, personal-care, and food industries to reduce storage and transportation costs and to provide desirable characteristics. The current study aimed to produce concentrated emulsions (50 wt % oil) using two natural emulsifiers, quillaja saponins and rhamnolipids. The impacts of emulsifier concentrations on the particle sizes, rheological properties, and stabilities of concentrated emulsions were evaluated. Emulsion particle sizes were negatively correlated with the concentrations of both quillaja saponins and rhamnolipids, and rhamnolipids were more effective in producing smaller droplets. Both emulsifiers formed stable concentrated emulsions against a series of environmental stresses, including various temperatures (30-90 °C), salt concentrations (≤200 mM NaCl), and pHs (pH 5-8). The rheology tests suggested that concentrated emulsions stabilized by quillaja saponins or rhamnolipids presented shear-thinning behaviors and had relatively low consistency coefficients.

Concentration effect of Quillaja saponin – Co-surfactant mixtures on emulsifying properties

HypothesisThis study examined the emulsifying properties of mixed surfactant systems of Quillaja saponins and food-grade co-surfactants (Na-caseinate, pea protein, rapeseed lecithin, and egg lecithin). We hypothesized to these mixtures may build mixed adsorption layers and thus enhance emulsion stabilization. ExperimentsOil-in-water emulsions (10%, pH 7) were prepared with different concentrations of co-surfactants (0.1–5.0%) alone or mixed with Quillaja saponins (0.05 or 0.5%). Dynamic interfacial tension measurements were performed to characterize the behavior of the surfactants at an oil-water interface. FindingsLow Quillaja saponin concentrations led to either no changes or substantial increases in particle sizes of protein stabilized emulsions, but d43-values decreased in lecithin stabilized emulsions at low lecithin concentrations. The dominating effect of Quillaja saponins at high concentrations led to formation of small droplets (d43≤2 µm) in all emulsions, except with 2.5% pea proteins. All co-surfactants showed synergistic or additive effects with respect to interfacial tension reductions upon addition of Quillaja saponins (except for egg lecithin with 0.005% Quillaja saponin addition). The results indicated a competing effect for saponin–protein interfaces, but formation of mixed saponin–lecithin interfaces, thus showing that the emulsion stabilization and interfacial properties can be tuned by specific binary surfactant mixtures.

Quillaja saponin-based hollow salt particles as solid carriers for enhancing sensory aroma with reduced sodium intake.

Dietary salt is a vital ingredient associated with sensory performance in processed foods, while reduced salt intake linked to public health is highly desired by consumers and food manufacturers. In this paper, quillaja saponin (QS) based hollow salt particles (∼10 μm) were fabricated by simple spray drying, and utilized as solid carriers to enhance sensory aromas with reduced sodium intake. QS-coated nanodroplets were firstly prepared as a reservoir for flavor oils (lemon and garlic oil), and then served as frameworks to construct hollow salt particles via general spray drying. Headspace gas chromatography-mass spectrometry (DHS-GC-MS) and panel sensory analysis conclude that the hollow salt particles loaded with flavor oils enhance typical aroma attributes and saltiness perception in comparison with their mixture control. The QS-based hollow salt particles could be developed into novel vehicles for improving flavor performance with reduced sodium intake, and furthermore used for delivery of hydrophobic bioactives in food systems.

Impact of oil droplet concentration on the optical, rheological, and stability characteristics of O/W emulsions stabilized with plant-based surfactant: Potential application as non-dairy creamers

The development of plant-based foods and beverages is becoming increasingly popular because of growing consumer concerns about perceived ethical, health, and environmental issues. The current study examined the influence of oil droplet concentration on the physicochemical properties of oil-in-water (O/W) emulsions stabilized with a plant-based surfactant. Emulsions were utilized as model creamers, which consisted of medium chain triglycerides (MCT) as the oil phase and quillaja saponin as a plant-based surfactant. The optical, rheological and stability properties of these model creamers were measured at varied oil content from 0 to 15%, at a constant surfactant-to-oil ratio (1:15). The model creamers had an appearance similar to that of commercial non-dairy creamers, and their whiteness increased with increasing droplet concentration due to enhanced light scattering: L* from 77 to 91 for creamer and L* from 5 to 55 for white coffee. The quillaja saponin-coated lipid droplets were stable to aggregation and gravitational separation when added to hot acidic coffee solutions (85°C, pH4.9), which was attributed to strong steric and electrostatic repulsions. The apparent viscosity of the model creamers increased with increasing droplet concentration due to increased frictional losses associated with the presence of the droplets. This study provides valuable information into the impact of oil content on the physicochemical properties of liquid creamers using plant based surfactants, which is important for the formulation of healthier products.

Preparation, characterization and immunological evaluation of alginate nanoparticles loaded with whole inactivated influenza virus: Dry powder formulation for nasal immunization in rabbits

It has become important to explore more efficient and feasible influenza vaccines, since epidemics of influenza virus cause hundreds of thousands of deaths all around the world. Improving immunogenicity of parentral influenza vaccines has given rise to mucosal delivery routes. In this study, alginate nanoparticles (NPs) were efficiently synthetized by ionic gelation method and influenza virus and CpG ODN or Quillaja Saponin (QS) adjuvants were actively incorporated into alginate NPs. The prepared particles were evaluated for both humoral and cellular immune responses in rabbits‘ nostrils. The vaccination started with a prime dose and followed by three boosters (two intranasal (IN) on days 45 and 60 and the last dose, intramuscular (IM) on day 75). HAI titer had increased in all the samples; although, only in the group received WV + CPG suspension reached to the protective HAI titer. All the immunized rabbits elicited significantly high sIgA levels on day 75, compared to the negative and the IM groups. At the end of the study, IN administration of CpG ODN adjuvant with virus antigen induced higher IgG level than the groups vaccinated with alginate NPs with or without CpG ODN (P < 0.001). As for the cellular immunity, CpG ODN was capable of inducing significant levels of IL-4 and TNF-α, either through inoculation along with the virus suspension or as incorporated in alginate NPs. According to the obtained data, CpG ODN adjuvant showed higher immunogenic potential as part of a vaccine delivery system than QS. Moreover, applying alginate polymer as a nasal delivery system carrier was not deemed immunogenic against influenza whole virus.