Food Emulsions Research Articles

How can food frequency questionnaire evaluate the intake of processed foods with added emulsifiers? A pilot study

SummaryEmulsifiers are widely used by food manufacturers, and their consumption has been linked to adverse health outcomes. The average dietary intake of emulsifiers has been poorly reported because no dietary assessment tool is yet available to determine their qualitative or quantitative intake. The present study aimed to validate a newly developed food frequency questionnaire (FFQ) for assessing the intake of foods with added emulsifiers. A cross‐sectional study was conducted on a sample of healthy female adults living in Saudi Arabia. All participants completed the FFQ alongside 3‐day food records (Reference method). Pearson's correlation test, cross‐classification analysis and weighted kappa (κw) statistics were used to assess the validity of the new FFQ against the reference method. The results showed variation in relative validity and level of agreement of food items and/or groups consumption between the two methods. Correlation coefficient values ≥0.5 were reported for some food items (i.e., condensed/evaporated milk, packaged powdered soup/broths and vegetable/nut purees). The FFQ demonstrated an acceptable degree of agreement between the two methods for the confectionery, dairy products and ‘other foods’ with ≥50% of participants classified into the same tertile by both methods (κw = 0.2–0.48). However, poor agreement outcomes were found with bakery products, processed meats and beverages with <50% of participants classified in the same tertile (κw < 0.2). The present study indicated that the new FFQ is a suitable qualitative tool for assessing intakes of food emulsifiers. However, the tool still needs further validation.

Modulation of rapeseed protein nanoparticles by interaction with chitosan: Enhancing the physical stability, antioxidant activity and β-carotene slow-release properties of Pickering emulsion

This study aimed to investigate the physical stability, oxidation, digestibility and β-carotene sustained-release properties of Pickering emulsions stabilized by rapeseed protein (RP) complexed with chitosan (CS). The results showed that adding CS to RP decreased the RP mean particle size from 3575.0 to 130.9 nm, increased its zeta-potential from 29.6 to 41.4 mV, changed its tertiary structure, and enabled its uniform dispersion. Additionally, CS addition improved RP interfacial properties at air/water and oil/water interfaces, thereby enhancing its emulsification activity and stability. Rheological property analysis exhibited that RP/CS complex had a smaller storage modulus (G′) and loss modulus (G") as well as a higher apparent viscosity. Moreover, the RP/CS complex stabilized emulsions showed a smaller average particle size of 100–1500 nm, a higher zeta-potential of 58–66 mV and better physical stability, thus better tolerating environmental factors such as time, temperature and salt ions. Furthermore, the RP/CS complex stabilized emulsions showed better antioxidant properties with a lower peroxide value (POV) and thiobarbituric acid reactant value (TBARS). Finally, the RP/CS complex emulsions exhibited better antidigestive stability and could slow down the β-carotene release rate. These results provide a theoretical basis for the application of RP/CS complex as a new food emulsifier in the nanocolloid transport system.

Tribological properties of real foods using extended Stribeck curves and their relationship with nutritional and rheological parameters.

The tribological properties of 19 commercial food products, grouped into six categories (yogurt, dressings, spreads, porridges, emulsified sauces, and syrups) were investigated in relation to their rheological (dynamic oscillatory shear test) and nutritional properties (fat, carbohydrate, and protein). A tribological system (a glass ball and three polydimethylsiloxane pins) generated the extended Stribeck curve, monitoring friction factors (f) over an extended range of sliding speed (v) (10-8 to 100 m/s). Tribological parameters (f, v) at four inflection points dividing the frictional regimes (X1, breakaway point between the static and kinetic regimes; X1-X2, boundary; X2-X3, mixed; X3-X4, hydrodynamic regimes) and the slope between X3 and X4 (s) were subjected to principal component analysis and hierarchical clustering on principal components, using rheological and nutritional parameters as quantitative supplementary variables. Tribological patterns were predominantly influenced by viscosity, viscoelasticity, yield stress, fat content, and the presence of particles (e.g., sugar, proteins, and fibers) and pasting materials (e.g., starches and modified starches). The 19 tribological patterns were classified into 3 clusters: low f and s for fat- and/or viscoelastic-dominant foods (Cluster 1), low f and high s for food emulsions and/or those with low extent of shear-thinning (Cluster 2), and high f at the boundary regime either for the most viscous foods or for those in the presence of particulates (Cluster 3). These results suggest that the compositional and rheological properties have a more profound impact on the classification of complex tribological patterns than the categories of food products.

Fabrication of pea protein isolate-stabilized oil-in-water emulsions with high freeze-thaw stability: Effect of high intensity ultrasonic on emulsions and interfacial protein structure

The poor freeze-thaw stability of plant protein-based emulsions posed a major challenge for their application in the cold chain foods. The present study successfully prepared oil-in-water emulsions stabilized solely with pea protein isolate (PPI) with excellent freeze-thaw stability using a facile high intensity ultrasonic (HIU)-assisted method. The optimized emulsion can endure three freeze-thaw cycles without stratification or oil leakage, maintaining oil droplet sizes at the nanometer scale. Furthermore, changes of interfacial protein structure induced by HIU were systematically investigated to reveal the stabilizing mechanism. The freeze-thaw stability of emulsions treated under varying intensities was evaluated based on changes in the appearance and oil drop size distribution. The results showed that the oil drop size of emulsions decreased from micron to nanometer and the freeze-thaw stability was significantly enhanced with the increase of HIU intensity. The emulsion exhibited optimized freeze-thaw stability under 800W. Subsequently, the effect of HIU on the structure of interfacial protein was analyzed through SDS-PAGE, –SH/S–S contents, UV spectrum, surface hydrophobicity, protein adsorption percentage, emulsifying activity and interfacial dilatational rheology. It was found that HIU triggered crosslinking of disulfide bonds among interfacial PPI molecules and enhanced the strength of the interface layer. Additionally, HIU promoted the unfolding of interfacial PPI structure, resulting in the improvement of surface hydrophobicity, emulsifying activity, and interfacial adsorption percentage of PPI. The study demonstrated the feasibility of using HIU to improve the freeze-thaw stability of oil-in-water emulsions stabilized with PPI and provided references for the fabricating of plant protein-based frozen emulsion foods.

Tannic acid/non-covalent interaction-mediated modification of hemp seed proteins: Focused on binding mechanisms, oil-water interface behavior, and rheological properties

In this study, hemp seed protein (HSP) was treated to prepare a hemp seed protein-tannic acid non-covalent complex (Nov-HSP). To obtain an emulsifier with excellent properties at the oil-water interface and to propose a potential mechanism of action. The results showed that the α-helix and β-sheet content of Nov-HSP decreased and the intensity of the UV absorption peak increased, respectively, compared with that of HSP. The positions of the maximum fluorescence emission peaks of the synchronized fluorescence spectra were red-shifted to 301.8 nm and 340.6 nm, respectively. Fluorescence quench analysis revealed that static quench occurred between tannins and HSP, with ΔH of −16.138 kJ/mol and ΔS of −0.1073 kJ/mol. The physicochemical and functional properties of HSP and Nov-HSP were analyzed, and it was found that the volume mean diameter of Nov-HSP was 449.28 nm, the absolute value of zeta potential was 20.52 mV, and the solubility was 33.42% at a tannic acid concentration of 1.0 mg/mL. Focusing on the oil-water interfacial properties of Nov-HSP as an emulsifier, it was found that having non-covalent binding effectively increased the diffusion rate of HSP at the interface, thus enhancing the rheological properties of the emulsion. And the emulsification activity index and emulsion stability index were improved to 71.67 m2/g and 32.01 min. These findings provide new perspectives for the phenolic compound-mediated structural remodeling of HSP, expanding its application in emulsion food production.

Characterization of bamboo shoot cellulose nanofibers modified by TEMPO oxidation and ball milling method and its application in W/O emulsion

It has rarely been reported that the modification of bamboo shoot nanofibers by oxidation combined with physical and applied in food emulsions. In this study, the combination of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation and the ball milling technique was employed to prepare bamboo shoot cellulose nanofibers (TOCNF) for W/O emulsions. A comparative study of the properties and structures of CNF prepared only by ball milling and TOCNF prepared by oxidation-ball milling was carried out, and a preliminary structural and rheological study of their application to emulsions was carried out. The results showed that TOCNF had higher water holding, swelling, and oil holding properties, cholesterol and glucose adsorption capacity than CNF. The combination of oxidative pretreatment and ball milling resulted in a dense entangled network structure, uniform particle size distribution, and high zeta potential value of TOCNF. The higher crystallinity of the TOCNF (68%) resulted in improved thermal stability. In addition, compared with the CNF-stabilized emulsion, with TOCNF dispersion as the internal aqueous phase, the emulsion droplets had a more uniform particle size distribution (6.61 ± 3.59 μm), higher gel strength, and thixotropic resilience of up to 71.24%. Thus, TEMPO oxidation combined with the ball milling method can be an effective means to improve nanofibers and provide a theoretical basis for expanding the application of bamboo shoot cellulose resources in the food colloid field.

Enriching the formulation of low-fat mozzarella cheese using micro-coated vitamin D3

PurposeThe use of polysaccharides increases solubility and consistency and causes functions such as viscosity? Moisture and food emulsifier stabilizer. This study aims to enrich the formulation of low-fat mozzarella cheese using microcoated vitamin D3 (VD3).Design/methodology/approachThis study investigates the addition of hydrocolloids to low-fat mozzarella cheese to enhance its properties and nutritional value. Tests were conducted on cheese samples with 0.05% and 0.25% hydrocolloid concentrations at various stages: before production and at three and six months’ postproduction. The samples were evaluated for elasticity, pH and solubility to select the best one, which was then fortified with VD3. The vitamin was microencapsulated using alginate and whey protein to shield it from light and oxygen, optimizing the formula using the response surface method. The fortified cheese was tested for VD3 content over its shelf life.FindingsResults indicated that all hydrocolloids tested improved moisture and meltability of the cheese while higher protein levels increased stretchability two to threefold. Rice starch hydrocolloid at 0.05% concentration was chosen due to superior sensory scores and minimal oil separation. This study concluded that VD3 levels remained stable during the cheese’s shelf life, suggesting that this approach could enhance the nutritional value of low-fat cheese without compromising its quality. Therefore, after examining the obtained results and comparing the regression models, the results indicated that the Quadratic model was chosen to investigate the effect of independent variables on the response rate, which had a statistically significant difference with other models (p = 0.0019). Also the results of the area under the curve and using the encapsulation efficiency equation, the percentage of microencapsulated vitamin was obtained, and according to the simulation results, the encapsulation efficiency was reported as 89.02%.Originality/valueDeveloping innovative functional dairy products fortified with VD3 could improve the vitamin D status in deficient populations. Therefore, these designs can be applied at industrial scales for functional cheese production.

Study on the influence of food emulsion components on its lubrication characteristics and smooth perception

Due to the increasing risk of obesity and cardiovascular diseases caused by high-fat diets, low-fat foods have become a priority demand for consumers’ health. However, the smoothness perception and scientific assessment methods of the existing low-fat foods should be improved. In this study, three food emulsions were prepared, and their lubrication characteristics, sensory evaluation of smoothness, and electroencephalogram (EEG) signals were assessed to preliminarily investigate the effects of food emulsion components on their above characteristics. The results showed that fat substitute (FSU) and fat could significantly reduce coefficient of friction (CoF) of the food emulsions, with average CoF reduced by 28% and 63% compared to the original food emulsions. In addition, fat-enriched food emulsions continued to exhibit excellent lubrication characteristics after adding artificial saliva, with an average CoF reduced by 31.1% compared to that of the food emulsions without artificial saliva. Both FSU and fat improved the smoothness of food emulsions, and the lubricating properties of fat were more pronounced, with fat-enriched food emulsion which could provide a substantial improvement in smoothness compared to the fat-free food emulsion. Comparison of subjects’ EEG signals revealed that food emulsion with lower CoF and higher smoothness triggered higher P3 amplitudes and longer latencies. These findings provide better insights into the scientific evaluation of food texture and the development of low-fat foods.

Epithelial barrier theory in the context of nutrition and environmental exposure in athletes.

Exposure to toxic substances, introduced into our daily lives during industrialization and modernization, can disrupt the epithelial barriers in the skin, respiratory, and gastrointestinal systems, leading to microbial dysbiosis and inflammation. Athletes and physically active individuals are at increased risk of exposure to agents that damage the epithelial barriers and microbiome, and their extreme physical exercise exerts stress on many organs, resulting in tissue damage and inflammation. Epithelial barrier-damaging substances include surfactants and enzymes in cleaning products, laundry and dishwasher detergents, chlorine in swimming pools, microplastics, air pollutants such as ozone, particulate matter, and diesel exhaust. Athletes' high-calorie diet often relies on processed foods that may contain food emulsifiers and other additives that may cause epithelial barrier dysfunction and microbial dysbiosis. The type of the material used in the sport equipment and clothing and their extensive exposure may increase the inflammatory effects. Excessive travel-related stress, sleep disturbances and different food and microbe exposure may represent additional factors. Here, we review the detrimental impact of toxic agents on epithelial barriers and microbiome; bring a new perspective on the factors affecting the health and performance of athletes and physically active individuals.

Commercial Tara Protein: Functional properties and use to stabilize sacha inchi oil emulsions obtained by ultrasound

Commercial tara protein (CTP) and sacha inchi oil are promising Peruvian products for forming food emulsions. The present work aimed (1) to characterize the functional properties of CTP as a new protein source (water and oil absorption, foam, and gelling capacity) and (2) to deepen the CTP to form sacha inchi oil emulsions. The CTP (2%, 4%, 6%) and oil concentration (15%, 20% and 25%) were evaluated for rotor-stator (RS) emulsion production. Final emulsions (RS-US) were produced with RS emulsions added with 2% tara gum and ultrasound homogenization at 75% power amplitude for 3 min. Emulsions were analyzed according to gravitational stability, droplet size, and optical microscopy. The results showed that the CTP presented a centesimal composition of 6.03% moisture, 45.16% proteins, 12.32% lipids, 2.49% fiber, 6.04% ashes, and 27.96% carbohydrates. CTP had a greater oil absorption (2.1442 ±0.26 g/g solids) than water absorption (1.8201 ±0.02 g/g solids), did not present foam formation, and the least gelation concentration was 18%. RS-US emulsions prepared with 25% oil and 2% or 4% protein had greater stability against the creaming index and phase separation during 4h, despite emulsion prepared with 15% oil presenting the lowest mean droplet size. In conclusion, the results show that commercial tara protein effectively prepared emulsions with a combined method (rotor-stator, ultrasound, and tara gum).

Effects of Adding Pectin to Milk in Varying Amounts on the Rheological Properties of Milk

Pectin, which is used as an additive in the food, cosmetics, pharmaceutical, and health sectors due to its safety, non-toxicity, low production cost, and high availability, is used as a thickener, gelling agent, brightener, stabilizer, emulsifier, and fat and sugar replacer in low-calorie foods. It is also used in milk and dairy products as a stabilizer to prevent proteins from clumping. In this study, the rheological properties of pectin and milk mixtures with pectin/milk powder (w/w) ratios of 0.1, 0.25, 0.5, 0.75, 1 and 1.5 were examined. First, a flow curve test was applied in the range of 0,01-1000 s-1 to obtain the viscosity curves and yield stress values of the samples. Then, an amplitude sweep test was performed at a fixed frequency of 10 rad/s and in the strain range of 0.01-100% to determine the linear viscoelastic range (LVR) of the samples and the solid and liquid structure of the samples. To determine the time-dependent behavior of the samples in non-destructive deformation, frequency sweep tests were performed at constant strain (0.01%) in the LVR range obtained from the amplitude sweep test and in the range of 0.1-100 rad/s. Finally, three interval thixotropy tests (3ITT) were performed to observe the structural recovery of the samples. As a result of rheological tests, it was determined that pectin-free milk showed Newtonian properties, other samples showed shear thinning properties, and viscosity values increased as the pectin rate increased. While all samples are solid at low strains, the liquid feature becomes dominant at high strains. It has been observed that as the pectin ratio in milk increases, the strain values at the yield point, where the liquid feature becomes dominant, also increase. Except for the sample with the highest pectin content, it was observed that the dominance of the storage modulus over the loss modulus was greater at low frequencies than at high frequencies. As a result of 3ITT, it was determined that the percentage of recovery at the 600th second increased as the pectin rate increased.

Food emulsifiers aggravate inflammation and oxidative stress induced by food contaminants in zebrafish

Food emulsifiers like glycerol monostearate (G) and Tween 80 (TW) are commonly used to help formation and maintain stability of emulsions. However, certain food contaminants and emulsifiers often co-occur in the same food item due to food culture and cooking methods. For this reason, the present study investigated interaction of toxic effect of emulsifiers (G and TW) and process contaminants (acrylamide (AA) and benzo [a]pyrene (BAP)) on zebrafish. Adult zebrafish were exposed to emulsifiers, food contaminants, or the combination through diet for 2 h and 7 days. Oxidative stress and inflammation caused by food contaminants were increased when food emulsifiers were present. These combined treatments also induced more severe morphological changes than the contaminant alone treatments. In the gut, disruption of villi structure and increased number of goblet cells was observed and in the liver there were increased lipid deposition, infiltration of immune cells, glycogen depletion and focal necrosis. Increased accumulation of AA and BAP in the liver and gut were detected after addition of emulsifiers, suggesting that emulsifiers can enhance absorption of diet-borne contaminants. Our results showed food emulsifiers and contaminants can interact synergistically and increase risk.

Exploring the knowledge and awareness of emulsifiers in food and non-food products among the community in Brunei Darussalam

The demand for halal products in both food and non-food sectors is directly correlated with the growth of the Muslim population. Hence, it encompasses the prerequisite for utilising halal ingredients in producing the final product. Furthermore, there is a growing trend in the use of emulsifiers as a key ingredient in food and non-food products, which raises concerns about their prevalence, origin and impact on consumers' health. This research aims to investigate the level of knowledge and awareness among the community in Brunei Darussalam about the presence, source and health consequence of emulsifiers in food and non-food items. A quantitative approach was executed in this study. A questionnaire was developed and made available online for distribution to the general public of Brunei Darussalam via social media platforms. The data obtained from participants was recorded and analysed using SPSS Statistics version 23. Overall, the sample population was predominantly comprised of females, youths of aged 18-24 years old, students, individuals with a Bachelor's degree and Muslims. The results showed that the participants, particularly females and current students were significantly more knowledgeable of emulsifiers in food than non-food products. However, the overall knowledge degree of the ingredient among the participants was moderate. Furthermore, most responses exhibited a poor awareness level regarding the sources of emulsifiers and an uncertainty of their effects on human health. In conclusion, the findings of the present study will benefit consumers, particularly Muslims in Brunei Darussalam, to make informed decision on their purchasing of products as the information provided in the research enables them to distinguish between halal and non-halal products.

Online Education on the Development of Functional Foods and the Nutrients Encapsulation

The modern society lifestyle triggers a tendency for people to consume fast food with high-calorie, low-nutrient, and low-fiber. Due to the COVID-19 pandemic, society is becoming more aware of maintaining health by consuming healthy and nutritious foods. Therefore, the target of this educational webinar program was educated individuals in the education sector, and they were expected to influence their surrounding communities to adopt healthy eating patterns through the consumption of functional foods. Oil-in-water (O/W) food emulsions such as milk, mayonnaise, and creamer are widely consumed in processed foods. The development of Fiber CrèmeTM creamer as a substitute for milk/coconut milk, which is low sugar, trans-fat-free, and high fiber, has been produced by PT. LNK to enhance the taste of processed foods and beverages. Compounds such as vitamins, minerals, and antioxidants can be encapsulated within the emulsion system, such as using Virgin Coconut Oil (VCO) in creamer products. This webinar was attended by 103 participants, with 80% coming from the education sector. The participants' high level of knowledge and awareness was reflected through online questionnaires and comments. This educational webinar encourages the community to sustainably enhance body immunity by consuming functional foods.

Influence of gelatinized octenyl succinic anhydride-modified waxy adlay seed starch on the properties of astaxanthin-loaded emulsions: Emulsion properties, stability and in vitro digestion properties

Octenyl succinic anhydride (OSA)-modified starch is a commonly used food emulsifier and its emulsifying properties are positively correlated with the degree of substitution (DS). However, the maximum concentration of OSA in starch approved by the FDA and the China National Food Safety Standards is 3%. This study aims to enhance the emulsifying properties of OSA-modified waxy adlay seed starch by gelatinization under a limited DS and investigate its use in preparing delivery systems. The gelatinized OSA starch exhibited a more flexible macromolecular structure and better emulsifying activity (20.19 m2/g). The gelatinized OSA starch-stabilized astaxanthin-loaded emulsions showed high retention of astaxanthin (>50%) and long-term stability (56 days). In vitro digestion, the emulsion system showed a protective effect on astaxanthin, and the bioaccessibility of astaxanthin was increased to 16.32%. This study indicated that gelatinization could enhance the emulsifying properties of OSA starch, and this starch-stabilized emulsion was an effective system for astaxanthin.

Isolation and characterization of nettle (Urtica dioica L.) seed proteins: Conversion of underutilized by-products of the edible oil industry into food emulsifiers

This study aimed to upcycle a byproduct of the edible oil industry, cold-pressed nettle seed meal (CPNSM), into a plant-based emulsifier, thereby increasing the sustainability of the food system. The protein content of the nettle seed protein (NSP) powder was 48.3% with glutamic acid (16.6%), asparagine (10.7%), and arginine (9.7%) being the major amino acids. NSPs had a denaturation temperature of 66.6 °C and an isoelectric point of pH 4.3. They could be used as emulsifiers to form highly viscous coarse corn oil-in-water emulsions (10% oil, 4% NSP). Nevertheless, 10-fold diluted emulsions exhibited rapid creaming under different pH (2–9), salt (0–500 mM NaCl) and temperature (>40 °C) conditions, but they were relatively stable to aggregation. Our findings suggest that NSPs could be used as emulsifiers in highly viscous or gelled foods, like dressings, sauces, egg, cheese, or meat analogs.

Stabilization of o/w emulsion using breadfruit (Artocarpus altilis) starch modified by heat moisture treatment, acetic acid and combination of both

Abstract Exploration to utilize breadfruit (Artocarpus altilis) starch as stabilizer in food emulsion is increasing significantly. Breadfruit starch modification using octenyl succinic anhydride (OSA) has successfully investigated, however some methods are rarely been applied for breadfruit starch. Therefore, this research aimed to examine the ability of breadfruit starch which was modified using heat moisture treatment (HMT), acetic acid, and combination of both to stabilize oil-in-water (o/w) emulsion. The variables investigated were: 1) the addition of 2% of breadfruit starch modified by HMT, acetic acid and combination of both methods, and 2) the percentage of oil (25% and 40%). The stability of o/w emulsion was measured by the creaming index (CI), emulsifying activity (EA), observation of visible boundaries during storage and the size of droplets using light microscope. The results showed that the highest CI value (53.7%) was obtained in an emulsion with 25% oil stabilized by acetic acid modified starch. The higher the oil concentration in emulsion, the smaller the droplets produced. The most stable emulsion was the one prepared by addition of 40% oil and stabilize by 2% modified breadfruit starch using acetic acid. This emulsion has 33.33% CI value, 47.5% EA after 10 days of storage with evenly distributed droplets and almost uniform in size.

Multiple-stage silica-assisted liquid-liquid extraction: A promising extraction method for fractionation Mono-diacylglycerols(MDAGs) based Palm Stearin

Palm stearin-based mono-diacylglycerols (MDAGs) are food emulsifiers that have not yet been widely developed. Monoacylglycerol (MAG) and diacylglycerol (DAG) are the predominant components of MDAGs. Fractionation of MDAGs into MAG and DAG was currently performed by molecular distillation, chromatography, crystallisation or supercritical CO2. In order to reduce production costs and increase production efficiency, a simpler technique for MDAG fractionation is required. A ternary diagram was used to determine the optimum solvent composition for the extraction of MDAGs. Three different extraction methods, i.e. solid-liquid extraction, liquid-liquid extraction and multiple-stage silica-assisted liquid-liquid extraction, were used to fractionate MDAGs. The multiple-stage silica-assisted liquid-liquid extraction provides better separation performance than solid-liquid and liquid-liquid extraction. The extraction method with hexane solvent composition was able to produce DAG-rich fractions with a purity of 81.05% DAG and 16.47% MAG, while the binary solvent composition of hexane:ethanol (8:2) was able to produce MAG-rich fractions with a purity of 13.33% DAG and 83.45% MAG. This extraction method combines two separation mechanisms, i.e. adsorption on silica and solubility in the corresponding solvent. The latter method has the potential for production MAG-rich fraction and DAG-rich fraction. According to their respective functions, each of these fractions can be further developed.

Effect of pH on the emulsifying performance of protein-polysaccharide complexes.

Protein-polysaccharide complexes have been successfully used for emulsion stabilization. However, it is unclear how the complex's surface charge influences aggregation stability and coalescence stability of emulsions, and whether a low charged interfacial film can still maintain the coalescence stability of oil droplets. In the present study, the effects of pH (around the pI of protein) on the aggregation and coalescence stability of emulsions were investigated. Whey protein isolate (WPI) and peach gum polysaccharides (PGP) complexes (WPI-PGP complexes) were synthesized at pH 3, 4 and 5. Their sizes were 598, 274 and 183 nm, respectively, and their ζ-potentials were +2.9, -8.6 and -22.8 mV, respectively. Interface rheological experiments showed that WPI-PGP complex at pH 3 had the lowest interfacial tension, and formed the softest film compared to the complexes at pH 4 and 5. Microfluidic experiments showed that all WPI-PGP complexes were able to stabilize droplets against coalescence within short timescales (milliseconds). At pH 3, no coalescence was observed even under conditions where the continuous phase flow influenced the shape of oil droplets (from spheres to ellipsoids). At pH 4 and 5, the model emulsions were stable over 16 days of storage, extensive aggregation and creaming occurred at pH 3 after 8 days. Importantly, no coalescence took place. The present study confirmed that the aggregation stability of the emulsions was mainly determined by the surface charge of the complex, whereas the coalescence stability of emulsions is expectedly determined by steric repulsion, providing new insights into how to prepare stable food emulsions. © 2024 Society of Chemical Industry.

Naproxen recovery by green emulsion liquid membranes based on soybean oil

Drugs are chemical substances that come from either natural occurrence or synthetic sources. These compounds are designed to have some pharmacological effects, give some benefits to society, and remain through time. Their bioaccumulation or their interactions with other chemicals has been considered as a health risk because they can cause adverse effects on ecosystems and human health. The Emulsion Liquid Membranes (ELM) technique is proposed as a useful and simple methodology in the drug elimination from sewage water. In recent years, some green methods integrated by vegetable oils have been reported; nevertheless, toxic carriers continue to be used. Soybean oil has been reported in stability studies and formulation improvement of cosmetic, food and pharmaceutical emulsions, but not in emulsions for drugs recovery. Thus, a methodology totally environmentally friendly was developed in this work, without carriers and using only soybean oil. The ELM was integrated by soybean oil + Abil EM 90® 0.25 wt% as organic phase; NaHCO3 0.1 mol⋅L−1 as internal aqueous phase and all these emulsified at 19000 rpm for 10 minutes and a VIAP/VOP ratio equal to 1:1 respectively. It was able to extract 81% of naproxen and subsequent 67% recovery in 5 minutes of stirring. It can be inferred that soybean oil is an effective and green option because it can act as a carrier and as a diluent in ELMs for drugs recovery.