Five/six carbon monosaccharides-glycated coconut protein-stabilized emulsions: Impact on stability and digestion.

Water-in-Water Emulsions, Ultralow Interfacial Tension, and Biolubrication

Effects of different pH conditions on interfacial composition and protein-lipid co-oxidation of whey protein isolate-stabilised O/W emulsions

1640. Second thoughts on rubratoxin B: Moss, M. O., Robinson, F. V. & Wood, A. B. (1968). Rubratoxin B, a toxic metabolite of Penicillium rubrum. Chemy Ind. p. 587

Whole soybean milk produced by a novel industry-scale micofluidizer system without soaking and filtering

Melittin Exerts Multiple Effects on the Release of Free Fatty Acids from L1210 Cells: Lack of Selective Activation of Phospholipase A2 by Melittin

Egg white proteins pose notable limitations in emulsion applications due to their inadequate wettability and interfacial instability. Polyphenol-driven alterations in proteins serve as an effective strategy for optimizing their properties. Herein, covalent and non-covalent complexes of egg white proteins-proanthocyanins were synthesized. The analysis of structural alterations, amino acid side chains and wettability was performed. The superior wettability (80.00° ± 2.23°) and rigid structure (2.95 GPa) of covalent complexes established favorable conditions for their utilization in emulsions. Furthermore, stability evaluation, digestion kinetics, free fatty acid (FFA) release kinetics, and correlation analysis were explored to unravel the impact of covalent and non-covalent modification on emulsion stability, dynamic digestion process, and interlinkages. Emulsion stabilized by covalent complex exhibited exceptional stabilization properties, and FFA release kinetics followed both first-order and Korsmeyer-Peppas models. This study offers valuable insights into the application of complexes of proteins-polyphenols in emulsion systems and introduces an innovative approach for analyzing the dynamics of the emulsion digestion process.

Pickering emulsions stabilized from natural sources are often used to load unstable bio-active ingredients, such as astaxanthin (AXT), to improve their functionality. In this study, AXT-loaded Pickering emulsions were successfully prepared by 2,2,6,6-tetramethy-1-piperidine oxide (TEMPO)-oxidized cellulose nanofibers (TOCNFs) from Undaria pinnatifida. The morphology analysis showed that TOCNFs had a high aspect ratio and dispersibility, which could effectively prevent the aggregation of oil droplets. The stable emulsion was obtained after exploring the influence of different factors (ultrasonic intensity, TOCNFs concentration, pH, and ionic strength). As expected, AXT-loaded Pickering emulsions showed good stability at 50 °C and 14 days of storage. The results of simulated in vitro digestion showed that the emulsions exhibited higher release of free fatty acids (FFAs) and bioaccessibility of AXT than those in sunflower oil. Hence, our work brought new insights into the preparation of Pickering emulsions and their applications in protection and sustained, controlled release of AXT.

Effects of some vertebrate hormones on lipid mobilization in the insect fat body

Emulsions are dispersions of one liquid in another that are commonly used in various products, and methods such as high-pressure homogenisers and colloid mills are used to form emulsions. The size and size distribution of emulsion droplets are important for the final product properties and thus need to be controlled. Rapid coalescence of droplets during emulsification increases droplet size and widens the size distribution, and therefore needs to be prevented. To increase stability of emulsions, emulsifiers are added to adsorb at the oil-water interface before droplets collide. The time allowed for emulsifier adsorption is typically in the range of sub-milliseconds to seconds and to optimise emulsification processes, emulsifier adsorption and coalescence stability need to be measured in this time-scale, for which the microfluidic methods described in this thesis were developed. Chapter 2 provides an overview of existing literature on cross-flow microfluidic emulsification. The effects of various parameters such as microfluidic design, shear forces, and interfacial tension forces on droplet formation and the resulting droplet size are discussed, as well as the use of microfluidics to produce food-grade emulsions. Based on this evaluation, the methods to elucidate interfacial tension and coalescence stability are chosen, and these are presented in the next chapters. To measure emulsifier adsorption in the sub-millisecond time-scale, a tensiometric method was developed using a cross-flow microfluidic Y-junction, which is described in Chapter 3. This method is based on the relation between droplet size and interfacial tension at the moment of droplet formation, which is referred to as the acting interfacial tension. The acting interfacial tension of a system with hexadecane as the dispersed phase and sodium dodecylsulfate (SDS, a model surfactant) solutions as the continuous phase was successfully measured for droplet formation times ranging from 0.4 to 9.4 milliseconds and with high expansion rates (100-2000 s-1). Comparison of these results with data from a drop tensiometer (a conventional, static, and supra-second time-scale method) indicates that mass transport in the microfluidic Y-junction is fast and probably not limited by diffusion. Emulsifier mass transport conditions were further investigated in Chapter 4. The continuous phase viscosity and velocity were systematically varied and the effect on the acting interfacial tension in presence of water-soluble SDS was measured. We found that the acting interfacial tension was independent of the continuous phase viscosity, but was inversely dependent on continuous phase velocity. Both aspects led us to conclude that convective emulsifier transport in the continuous phase determines the acting interfacial tension in the Y-junction. When using oil-soluble surfactant Span 20 (dissolved in hexadecane), the acting interfacial tension also decreased with increasing continuous phase velocity, and we therefore concluded that convection also dominated mass transport of emulsifiers dissolved in the to-be-dispersed phase. The Y-junction method was used in Chapter 5 to elucidate the effect of the dispersed phase viscosity on adsorption of the food-grade emulsifiers Tween 20 (dissolved in the continuous water phase) and Span 20 (dissolved in the dispersed oil phase). A reduction in dispersed phase viscosity sped up adsorption of Tween 20, probably because the shorter hydrocarbon made intercalation of the hydrophobic surfactant tail at the interface easier. Dispersed phase viscosity had an even greater effect on adsorption of Span 20 because convective transport towards the interface was increased. Next to interfacial tension, also coalescence can be measured with microfluidics and a microfluidic collision channel was used in Chapter 6 to measure emulsion coalescence stability shortly after droplet formation under flow. Coalescence of emulsions stabilised with proteins was measured at various concentrations, pH values, and adsorption times. We found that protein concentrations just below the concentration needed for monolayer surface coverage may be used effectively. β-lactoglobulin-stabilised emulsions were most stable. Emulsions stabilised with whey protein isolate (with as main component β-lactoglobulin), were less stable and when these proteins were oxidised, this led to reduced stability, therewith indicating that also the oxidative state of proteins needs to be considered in emulsion formulation. The relevance of our work for microfluidic research and industrial emulsification processes is discussed in Chapter 7. Microfluidic devices can be used to study emulsion formation and stability under conditions relevant to industrial emulsification processes; at short time-scales and with convective mass transport. In this thesis we used various food-grade ingredients, and with that application in that field has come closer. We expect that the findings on emulsions can also be applied on foams. With the discussed microfluidic devices different aspects that are important for emulsion formation can be decoupled: for example interfacial tension during droplet formation and emulsion coalescence stability. Furthermore, microfluidic methods are available to for example gain insight in emulsion interface mobility and emulsion storage stability, and we envision that all these microfluidic methods will lead to faster ingredient screening, lower ingredient usage, and more energy efficient emulsion production.

Synergetic interfacial adsorption of protein and low-molecular-weight emulsifiers in aerated emulsions

This research presents a rigorous comparative analysis of high‐pressure homogenization (HPH) and microfluidization (MF) for the production of krill oil (KO) emulsions, scrutinizing their impact on oxidative stability, bioaccessibility, and the behavior under in vitro simulated digestion. Our findings revealed that MF emulsions possessed a distinct advantage, with a droplet size and distribution that promoted exceptional oxidative stability, evidenced by a sustained reduction in oxidative markers and enhanced retention of bioactive components, including EPA and DHA, and the potent antioxidant astaxanthin. In contrast, HPH yielded larger and less uniform particles, correlating with diminished stability. The in vitro digestion studies underscored the superior bioaccessibility of MF emulsions, with a pronounced release of free fatty acids during the intestinal phase, indicative of an optimized digestion and absorption process due to the smaller droplet size of the emulsions. The study's insights advocate for the adoption of microfluidization in the food industry for the development of advanced delivery systems for n‐3 fatty acids, particularly in the context of KO‐based products. The technique shows promise in enhancing the quality, stability, and bioavailability of these products, which are rich in health‐promoting lipids. The microfluidization technique emerges as a promising avenue for the fortification of a diverse range of commercial food, beverage, and pharmaceutical products with lipids that contribute to health and wellness.

Biopolymer Stabilized Emulsions Improved Storage Stability and In Vitro Bioaccessibility of Lutein

3-Chloropropane-1,2-diol (3-MCPD) esters are food processing contaminants, and are known to be potentially carcinogenic. The main purpose of this study was to determine whether the emulsion technique increases the absorption of this contaminant, and to develop strategies to reduce their absorption. 3-MCPD ester contents in edible oils (hazelnut, walnut, sunflower, soybean, corn, and olive oil) were determined. Refined olive oil contained the highest 3-MCPD ester level (1.7749 ± 0.1262 mg/kg). Then, emulsions (fine, medium, coarse) were prepared with 0.15-2% emulsifier (whey protein isolate) and 10% oil using microfludizier at 3-10 kpsi pressure. The free fatty acid release was investigated using an in vitro digestion model, and the bioaccessibility was calculated. Methylthiazole tetrazolium (MTT) cell viability method was used to perform toxicity tests. The zeta potential and droplet size of the Samples were measured after each digestion phase. The emulsion with the smallest particle size (389 nm) resulted in the highest release of free fatty acid (85.26%) during small intestinal phase. Fine emulsions also resulted in the highest 3-MCPD ester bioaccesibility (95%). During in vitro digestion, droplet size increased at stomach phase for all emulsion types (Figure 1). When an indigestible oil, such as lemon oil, was added to the oil phase of the fine emulsion (up to 30%), the release of free fatty acid decreased by up to 30% as expected and bioaccessibility decreased by up to 45%. The micelle phase of the fine and medium emulsion had a toxic effect on the fibroblast cell line (Figure 2). When the particle size increased and lemon oil was added to the oil phase of the emulsion, the percent viability increased. Briefly, there are two ways to reduce the absorption of 3-MCPD esters in food emulsions: producing emulsions with larger particle size, or adding indigestible oil to the oil phase.

Anthocyanins belong to the most important hydrophilic plant pigments. Outside their natural environment, these molecules are extremely unstable. Encapsulating them in submicron-sized containers is one possibility to stabilize them for the use in bioactivity studies or functional foods. The containers have to be designed for a target release in the human gastrointestinal system. In this contribution, an anthocyanin-rich bilberry extract was encapsulated in the inner aqueous phase of water-in-oil-in-water-double emulsions. The physical stability as well as the release of free fatty acids and encapsulated, bioactive substances from the emulsions during an in vitro gastrointestinal passage were investigated. The focus was on the influence of emulsion microstructural parameters (for example, inner and outer droplet size, disperse phase content) and required additives (emulsifier systems), respectively. It could be shown that it is possible to stabilize anthocyanins in the inner phase of double emulsions. The release rate of free fatty acids during incubation was independent of the emulsifier used. However, the exterior (O/W)-emulsifier has an impact on the stability of multiple emulsions in gastrointestinal environment and, thus, the location of release. Long-chained emulsifiers like whey proteins are most suitable to transport a maximum amount of bioactive substances to the effective location, being the small intestine for anthocyanins. In addition, it was shown that the dominating release mechanism for entrapped matter was coalescence of the interior W(1) -droplets with the surrounding W(2) -phase.

Emulsion refers to a mixture that includes two or more liquid phases. The uses of emulsions are found in several chemical, energy, and environmental industries such as the food, health care, chemical synthesis, and firefighting sectors. Water‐in‐oil emulsions are formed spontaneously during oil production when oil and water are mixed together and in the presence of asphaltene as a naturally occurring surfactant. For operational and economic reasons, oil emulsions need to be treated to recover both oil and water phases. To develop more efficient emulsion treatments, it is essential to have a better understanding of the factors that affect emulsion formation and stability. The droplet size variation is an important parameter that influences the stability and rheological characteristics of the emulsions. In addition, the available interfacial area for any possible chemical reactions might affect the behaviours and properties of the emulsions in various transport phenomena systems. The adequate knowledge of the factors and mechanisms affecting the droplet size and emulsion stability still needs further engineering and research activities. This study is aimed to provide a comprehensive literature review on the formation of water/oil emulsions and their stability in various physical systems (e.g., pipeline networks and porous media). In this review, fundamental aspects of emulsions, emulsion formation mechanisms, analytical models, and numerical solutions for the description and characterization of the behaviours of emulsions in porous media and/or separators are discussed. The effects of different fluid properties, physical model characteristics, and operational conditions on emulsion behaviours are studied. This paper also summarizes the previous experimental and modelling studies and methodologies with a focus on reliable laboratory equipment/tools and simulation and modelling packages/strategies for the investigation of emulsion stability and droplet size distribution where a systematic parametric sensitivity analysis to study various effects of important thermodynamic, process, and medium properties on the targeted variables is conducted. This review manuscript provides useful guidelines to characterize and model emulsions and their behaviours in different industrial sectors, which will considerably help to conduct better design and optimal operation of corresponding equipment.