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The impact of lutein-loaded nanoemulsions and excipient nanoemulsions mixed with lutein-based dietary supplements (capsules and soft gels) on the bioaccessibility of lutein was explored using a simulated gastrointestinal tract (GIT). The particle size, particle size distribution, ζ-potential, microstructure, lipid digestibility, and lutein bioaccessibility of all the samples were measured after they were exposed to different environments (stomach and small intestine environments) within a simulated GIT. As expected, the bioaccessibility of lutein from the capsules (1.5%) and soft gels (3.2%) was relatively low when they were administered alone. However, the co-administration of excipient nanoemulsions significantly increased the bioaccessibility of lutein from both the capsules (35.2%) and soft gels (28.7%). This phenomenon was attributed to the fast digestion of the small oil droplets in the excipient nanoemulsions and the further formation of mixed micelles to solubilize any lutein molecules released from the supplements. The lutein-loaded nanoemulsions exhibited a much higher lutein bioaccessibility (86.8%) than any of the supplements, which was attributed to the rapid release and solubilization of lutein when the lipid droplets were rapidly and extensively digested within the small intestine. This study indicates that the bioaccessibility of lutein is much higher in nanoemulsion droplets than that in dietary supplements. However, consuming dietary supplements in the presence of nanoemulsion droplets can greatly increase lutein bioavailability. The results of this study have important guiding significance for the design of more effective lutein supplements.

The in vitro digestion model developed by the INFOGEST international consortium is widely used to simulate the physicochemical processes occurring inside the human gastrointestinal tract (mouth, stomach, and small intestine) during the digestion of foods. In this review, we provide a brief overview of the INFOGEST method and the procedures used to measure the digestion of macronutrients (lipids, proteins, and starch), the bioaccessibility of bioactive agents (vitamins, minerals, and nutraceuticals), and the changes in the structure and physical properties of foods under gastrointestinal conditions (particle size, charge, and location). We then review the application of the INFOGEST method for monitoring the gastrointestinal fate of different kinds of foods and beverages, including dairy, egg, meat, seafood, fruit, vegetable, cereal, and emulsified products. We also discuss the application of this method for studying the digestibility of next-generation plant-based foods, such as meat, seafood, dairy, and egg analogs. Finally, the benefits and limitations of this standardized in vitro digestion model are assessed. Expected final online publication date for the

The production of plant-based fish alternatives that look, feel, taste, and cook like real fish is critical for widespread consumer acceptance. Consequently, a thorough understanding of the properties of real fish is critical for the successful design of high-performance plant-based fish analogs. In this study, we investigated changes in the optical, mechanical, and water holding properties of Atlantic salmon during simulated cooking at different temperatures. Differential scanning calorimetry and diffusive wave spectroscopy exhibited characteristic peaks around 40 °C (myosin and collagen) and 72 °C (actin), which caused appreciable changes in the salmons’ physicochemical properties. The textural properties of salmon during simulated cooking were characterized using a dynamic shear rheometer and texture analyzer. Changes in color, cook loss, and surface area were related to the cooking temperature. This study provides valuable insights into the relationship between protein denaturation, protein aggregation, microstructural changes, and texture of real fish. This information will be useful for creating higher quality plant-based fish analogs.

Many plant-based milks lack key micronutrients found in bovine milk, such as calcium and vitamin D. In this study, we fortified almond milk with these two micronutrients and used a standardized gastrointestinal model to examine the impact of product formulation on their bioaccessibility. The impact of different forms (CaCl2 versus CaCO3) and concentrations (0, 1, or 2 g per 240 mL) of calcium on the physicochemical properties, lipid digestibility, and vitamin D bioaccessibility was examined. Soluble calcium (CaCl2) promoted particle aggregation by reducing the electrostatic repulsion, while colloidal calcium (CaCO3) did not because there were fewer free calcium ions. High levels of calcium (soluble or insoluble) reduced vitamin D bioaccessibility, which was attributed to insoluble calcium soap formation in the small intestine. Calcium bioaccessibility was higher for CaCO3 than CaCl2. These findings are useful for the development of nutritionally fortified plant-based milks with improved physicochemical and nutritional properties.

Many lipophilic polyphenols have low bioavailability because of their poor solubility and chemical stability within the human gut. The encapsulation of these polyphenols within digestible lipid droplets can improve their solubility and stability. However, there is currently a poor understanding of how the molecular and physicochemical properties of specific polyphenols impact these characteristics. In this study, the factors influencing the solubility and stability of different polyphenols (curcumin, resveratrol, and quercetin) under simulated gastrointestinal conditions were examined when they were delivered in the form of soybean oil-in-water nanoemulsions containing quillaja saponin-coated droplets (d32 ≈ 0.15 μm; ζ = -63 mV; pH 5). The polyphenols were loaded into the lipid droplets using a pH-driven method, which is based on the pH-dependent electrical charge, oil-water partitioning, and water-solubility of these molecules. The encapsulation efficiency of all three polyphenols was relatively high (75-87%). However, their chemical stability under gastrointestinal conditions (i.e., the % remaining after exposure to gastrointestinal conditions) differed considerably: quercetin (44%), curcumin (92%), and resveratrol (100%). This effect was mainly attributed to the lower logD value of quercetin (2.17) than those of resveratrol (3.39) and curcumin (4.12). As a result, a high fraction (>50%) of quercetin was located within the aqueous gastrointestinal fluids, where it would be more prone to chemical degradation or precipitation. The fraction of the polyphenols solubilized in the gastrointestinal fluids (bioaccessibility) followed a different trend: curcumin (57%) < quercetin (73%) < resveratrol (76%). This effect was attributed to the chemical instability and/or binding of curcumin with other molecules in the simulated intestinal conditions. These results provide useful information for designing nanoemulsion-based delivery systems to improve the efficacy of lipophilic polyphenols.

We systematically investigated the impact of oil droplet diameter (≈0.15, 1.6, and 11 μm) on the bioaccessibility of three oil-soluble vitamins (vitamin A palmitate, vitamin D, and vitamin E acetate) encapsulated within soybean oil-in-water emulsions stabilized by quillaja saponin. Lipid digestion kinetics decreased with increasing droplet size due to the reduction in oil-water interfacial area. Vitamin bioaccessibility decreased with increasing droplet size from 0.15 to 11 μm: 87 to 39% for vitamin A; 76 to 44% for vitamin D; 77 to 21% for vitamin E. Vitamin bioaccessibility also decreased as their hydrophobicity and molecular weight increased, probably because their tendency to remain inside the oil droplets and/or be poorly solubilized by the mixed micelles increased. Hydrolysis of the esterified vitamins also occurred under gastrointestinal conditions: vitamin A palmitate (∼90%) and vitamin E acetate (∼3%). Consequently, the composition and structure of emulsion-based delivery systems should be carefully designed when creating vitamin-fortified functional food products.

This study investigated the changes in the structural and functional properties of various adlay starch-based polymers that occur during low moisture extrusion. The water absorption index, water solubility index, color, and morphological, pasting, and thermal properties of the adlay flours were investigated. Extrusion significantly decreased their contents (starch > protein > fiber > lipids). The color of the adlay flour darkened after extrusion, primarily due to the Maillard reaction and caramelization. Scanning electron microscopy revealed various cracks, pits, and holes on the surface of the extruded flour without defatting for both the extruded brown adlay and the extruded polished adlay. Extrusion caused molecular degradation of the extruded starch, decreasing its swelling power in hot water. The ΔH values (0.19-0.71 J/g) of the extrudates revealed that the starch granules were not fully gelatinized. These results provide a theoretical basis for further explorations of the interactions of adlay macromolecules by extrusion.

Food, nutrition, and pharmaceutical scientists are trying to elucidate the major factors impacting the bioavailability of macronutrients (e.g., lipids) and micronutrients (e.g., vitamins) so as to improve their efficacy. Currently, there is still a limited understanding of how food matrix effects impact digestion and bioaccessibility determined under the INFOGEST model, which is currently the most widely used standardized in vitro gastrointestinal model. Therefore, we examined the impact of corn oil concentration on lipid digestion and β-carotene bioaccessibility using model food emulsions. For all oil concentrations tested (2.5 to 20%), complete lipid digestion was achieved using fed-state gastrointestinal conditions, which could only be seen if a back-titration was performed. The particle size and negative surface potential on the mixed micelles formed at the end of the small intestine phase both increased with increasing oil concentration, which was attributed to the generation of more free fatty acids. The β-carotene bioaccessibility increased when the oil concentration was raised from 2.5 to 10% due to the increased solubilization capacity of the mixed micelles, but then it decreased when the oil concentration was raised further to 20% due to precipitation and sedimentation of some of the β-carotene. The maximum β-carotene bioaccessibility (93.2%) was measured at 10% oil. These results indicate that the oil concentration of emulsions influences β-carotene bioaccessibility by altering digestion, solubilization, and precipitation processes. This knowledge is important when designing more effective functional or medical food products.

Consumption of sufficiently high quantities of dietary fibers has been linked to a range of health benefits. Recent research, however, has shown that some dietary fibers interfere with lipid digestion, which may reduce the bioavailability of oil-soluble vitamins and nutraceuticals. For this reason, we examined the impact of a cationic polysaccharide (chitosan) on the bioaccessibility of vitamin D using the standardized INFOGEST in vitro digestion model. The vitamin D was encapsulated within an emulsion-based delivery system that contained whey protein-coated corn oil droplets. Our results showed that chitosan promoted severe droplet flocculation in the small intestine and reduced the amount of free fatty acids detected using a pH-stat method. However, a back-titration of the digested sample showed that the lipids were fully digested at all chitosan levels used (0.1-0.5%), suggesting that chitosan may have bound some of the free fatty acids released during lipid digestion. The presence of the chitosan decreased the bioaccessibility of vitamin D by about 37%, but this effect did not depend strongly on chitosan concentration (0.1-0.5%). It was hypothesized that chitosan bound to the vitamin-loaded mixed micelles and promoted their precipitation. The knowledge gained in this study might provide useful insights in designing emulsion-based delivery systems with high vitamin bioaccessibility.

Recently, the standardized in vitro digestion model ("INFOGEST method") used to evaluate the gastrointestinal fate of foods has been revised and updated (Brodkorb et al., 2019, Nat. Protoc., 2019, 14, 991-1014). Under fed state conditions, the calcium level used in this model is fixed and relatively low: 0.525 mM. In practice, the calcium concentration in the human gut depends on the nature of the food consumed and may vary from person-to-person. For this reason, we examined the impact of calcium concentration on the gastrointestinal fate of a model nutraceutical delivery system. The effect of calcium level (0.525-10 mM) on lipid digestion and β-carotene bioaccessibility in corn oil-in-water nanoemulsion was investigated using the INFOGEST method. At all calcium levels, the lipids were fully digested, but this could only be established by carrying out a back titration (to pH 9) at the end of the small intestine phase. Conversely, the bioaccessibility of β-carotene decreased with increasing calcium levels: from 65.5% at 0.525 mM Ca2+ to 23.7% at 10 mM Ca2+. This effect was attributed to the ability of the calcium ions to precipitate the β-carotene-loaded mixed micelles by forming insoluble calcium soaps. The ability of calcium ions to reduce carotenoid bioaccessibility may have important nutritional implications. Our results show that the bioaccessibility of hydrophobic carotenoids measured using the INFOGEST method is highly dependent on the calcium levels employed, which may have important consequences for certain calcium-rich foods. Moreover, we have shown the importance of carrying out a back titration to accurately measure free fatty acid levels in the presence of low calcium levels.

RuBisCO protein, which can be isolated from abundant and sustainable plant sources, can mimic some of the desirable functional attributes of egg white proteins. In this study, plant-based egg white analogs were successfully produced using 10 w% RuBisCO solutions (pH 8). These protein solutions had similar apparent viscosity-shear rate profiles, shear modulus-temperature profiles, gelling temperatures, and final gel strengths as egg white. However, there were some differences. RuBisCO protein gels were slightly darker than egg white, which was attributed to the presence of phenolic impurities. Moreover, RuBisCo proteins exhibited a single thermal transition temperature (∼66 °C) whereas egg white proteins exhibited two (∼66 and ∼81 °C). RuBisCO gels were more brittle but less chewy and resilient than egg white gels. This study provides valuable insights into the potential of RuBisCO protein for formulating plant-based egg white analogs.

Lipophilic polyphenol compounds (LPCs) are claimed to exhibit a broad spectrum of biological activities that may improve human health and wellbeing, including antioxidant, anti-inflammatory, and anti-cancer properties. Nanoemulsion-based delivery systems have been developed to encapsulate LPCs so as to increase their food matrix compatibility, physicochemical stability, and bioavailability. LPCs vary in their structural features, including the number and position of phenolic hydroxyl, ketone, and aliphatic groups, which results in different molecular, physicochemical, and gastrointestinal properties. In this study, we examined the impact of plant-based carrier oils (coconut, sunflower, and flaxseed oils) and LPC type (curcumin, resveratrol, and quercetin) on the in vitro gastrointestinal fate of polyphenols loaded into quillaja saponin-stabilized nanoemulsions. Coconut oil contains high levels of medium-chain saturated fatty acids (MC-SFAs), sunflower oil contains high levels of long-chain monounsaturated fatty acids (LC-MUFAs), and flaxseed oil contains high levels of long-chain polyunsaturated fatty acids (LC-PUFAs). The encapsulation efficiency and gastrointestinal stability of the LPCs were slightly lower in the MC than the LC oils. Differences in the gastrointestinal stability of the three LPCs were linked to differences in their oil–water partition coefficients. Some of the LPCs inhibited lipid digestion for certain oil types. In particular, resveratrol retarded the digestion of all three oils, but it still had the highest GIT stability and bioaccessibility. This study provides valuable information about the gastrointestinal fate of LPC-loaded nanoemulsions and highlights important differences in the behavior of LPCs with different characteristics. This knowledge may facilitate the design of more effective plant-based delivery systems for bioactive lipophilic polyphenols.

Many plant-based milks lack key micronutrients found in bovine milk, such as calcium and vitamin D. In this study, we fortified almond milk with these two micronutrients and used a standardized gastrointestinal model to examine the impact of product formulation on their bioaccessibility. The impact of different forms (CaCl

Zein is widely used to encapsulate non-polar bioactives due to its ability to form protein nanoparticles with hydrophobic interiors. In this study, a simple pH-driven method, which does not use organic solvents, was employed to fabricate zein-rhamnolipid composite nanoparticles. An alkaline zein solution (pH 12.0) was mixed with an acidic rhamnolipid solution (pH 2.0), which led to the spontaneous formation of composite nanoparticles (pH 7.0). The possibility of using these nanoparticles to encapsulate and deliver curcumin was then studied. Nanoparticle properties, such as size and charge, were mainly determined by the mass ratio of zein-to-rhamnolipid used. The nanoparticles formed were spherical and relatively small (d ≈ 100 nm) according to dynamic light scattering and transmission electron microscopy. Nanoparticle suspensions remained stable from pH 5 to 9 but aggregated under more acidic conditions. At neutral pH, the nanoparticles were stable at low ionic strengths (

The food, cosmetics, and personal care industries are increasingly interested in replacing synthetic colorants with natural alternatives. Anthocyanin is a renewable and sustainable source of plant-derived pigment. However, their application in commercial products is often limited because of their susceptibility to chemical degradation, which leads to color fading and/or a change in hue. In this study, we examined the possibility of protecting anthocyanin from degradation by encapsulating them within the inner water phase of a water-in-oil-in-water (W/O/W) emulsion. Polyglycerol polyricinoleate (PGPR) was used as a hydrophobic emulsifier, while quillaja saponin was used as a hydrophilic emulsifier. First, W/O emulsions containing 20% aqueous phase and 80% oil phase (PGPR in corn oil) were prepared using a microfluidizer. Second, W/O/W emulsions were prepared by blending 20% W/O emulsion with 80% aqueous phase (saponin in water) using a high-shear mixer. Changes in color, particle size, charge, and anthocyanin leakage of the emulsions were measured when the external aqueous phase was changed from pH 7 to 3. Anthocyanin encapsulation significantly slowed down pH-induced color changes, possibly because the internal aqueous phase had a different pH to the external one. Anthocyanin transfer between aqueous phases depended on pH, temperature, and initial location. Our results suggest that multiple emulsions may be useful for encapsulation and protection of natural colors.

These is some interest in replacing digestible fats with indigestible ones to decrease the energy-density of foods. The utilization of indigestible oils, however, may have unforeseen nutritional consequences, such as the reduction of vitamin bioavailability. In this study, the impact of an indigestible oil on the bioaccessibility of emulsified vitamin D3 (VD) was examined. We prepared four kinds of nanoemulsions using different combinations of a digestible oil (DO) and an indigestible oil (IO): DO only; IO only; an oil mixture (OM) consisting of 1:1 DO:IO mixed before homogenization; and, an emulsion mixture (EM) consisting of 1:1 DO:IO nanoemulsions mixed after homogenization. A gastrointestinal tract (GIT) model was employed to elucidate the kinetics of VD bioaccessibility from the nanoemulsions. Both the lipid digestion rate and vitamin bioaccessibility decreased in the same order: DO > OM ≈ EM > IO. The change in vitamin bioaccessibility over time under simulated small intestine conditions was also measured. With the exception of the IO nanoemulsions, the vitamin bioaccessibility increased to a maximum value after around 30 min, but then decreased during the following 24 h. This effect was attributed to an initial solubilization of the vitamin within the mixed micelles, followed by their precipitation during prolonged incubation. Our results show that lipid digestion, micelle solubilization, and micelle aggregation impact the in vitro bioaccessibility of vitamin D. This knowledge may be helpful for designing more efficacious nanoemulsion-based delivery systems for fat-soluble vitamins.

Fine titanium dioxide (TiO2) particles have been used as additives (E171) to modify the optical properties of foods and beverages for many years. Commercial TiO2 additives, however, often contain a significant fraction of nanoparticles (diameter

Inorganic or organic nanoparticles are often incorporated into foods to enhance their quality, stability, nutrition, or safety. When they pass through the gastrointestinal environment, the properties of these nanoparticles are altered, which impacts their biological effects and potential toxicity. Consequently, there is a need to understand how different kinds of nanoparticles behave within the gastrointestinal tract. In this article, the current understanding of the gastrointestinal fate of nanoparticles in foods is reviewed. Initially, the fundamental physicochemical and structural properties of nanoparticles are discussed, including their compositions, sizes, shapes, and surface chemistries. Then, the impact of food matrix effects and gastrointestinal environments on the fate of ingested nanoparticles is discussed. In particular, the influence of nanoparticle properties on food digestion and nutraceutical bioavailability is highlighted. Finally, future research directions are highlighted that will enable the successful utilization of nanotechnology in foods while also ensuring they are safe.

Electrically charged food-grade biopolymers can be used to form multilayer coatings around the lipid droplets in oil-in-water emulsions using a sequential layer-by-layer electrostatic deposition approach. In principle, this approach can be used to improve the stability and enhance the functionality of food emulsions. In this study, multilayer coatings were formed from saponins, polypeptides, and polysaccharides using medium chain triglyceride (MCT) lipid droplets as templates (pH 4.0). First, an emulsion containing negatively charged lipid droplets was created using quillaja saponin (QS) as an anionic emulsifier. Second, these anionic droplets were coated with a cationic polypeptide (poly-L-lysine, PLL) to form positively-charged droplets. Finally, these cationic droplets were coated with a negatively-charged polysaccharide, either pectin (PE) or κ-carrageenan (KC), to form anionic droplets. Overall, the 1-layer emulsions had the best resistance to salt, pH, and heat, indicating that quillaja saponins were effective emulsifiers. The 2-layer emulsions had better pH-stability than the 3-layer emulsions, which tended to strongly aggregate under acidic conditions. Conversely, the 3-layer emulsions had better salt-stability than the 2-layer emulsions, which tended to aggregate strongly even at low salt levels (50–100 mM NaCl). All the emulsions were relatively stable to heating (90 °C, 30 min). Overall, our results provide useful insights into the formulation of stable multilayer emulsions from food-grade emulsifiers and biopolymers. There appears to be little advantage to using the multilayer technology to enhance the physical stability of saponin-coated lipid droplets, but there may be advantages in terms of extending their functional properties, which will be explored in future studies.

Water-in-oil-in-water (W/O/W) emulsions can be designed to encapsulate, protect, and release both hydrophilic and hydrophobic functional compounds. In this study, we examined the impact of crystallizing the fat phase on the resistance of W/O/W emulsions to osmotic stress, with the aim of developing osmotic-responsive systems. Polyglycerol polyricinoleate (PGPR) was used as a hydrophobic surfactant to stabilize the inner water droplets, while Quillaja saponin and whey protein isolate (WPI) were used as hydrophilic surfactants to coat the oil droplets. The impact of fat crystallization was examined by using either a liquid (soybean oil, SO) or semi-solid (hydrogenated soybean oil, HSO) fat as the oil phase. An osmotic stress was generated by establishing a sucrose concentration gradient between the internal and external water phases. Alterations in the droplet size, morphology, and stability of the W/O/W emulsions was measured when the sucrose concentration gradient was changed. The W/O droplets in the SO-emulsions swelled/shrank when the external sucrose concentration was below/above the internal sucrose concentration, which is indicative of water diffusing into/out of the droplets. Conversely, there was no change in the size of the W/O droplets in the HSO-emulsions under the same conditions, which was attributed to the mechanical strength of the fat crystal network resisting swelling or shrinking. HSO-emulsions did exhibit swelling when they were heated above a critical temperature, due to melting of the fat crystals and disruption of the crystal network. Our results demonstrate that crystallization of the oil phase of W/O/W emulsions can prevent water transport due to osmotic stress, which may be useful for developing temperature-triggered delivery systems for application in foods, cosmetics, pharmaceuticals, or personal care products.

Mixed Pickering emulsions were prepared by blending anionic nanocellulose-stabilized lipid droplets with cationic nanochitin-stabilized lipid droplets. Changes in the surface potential, particle size, shear viscosity, and morphology of the mixed emulsions were characterized when the droplet mixing ratio was varied. Emulsion properties could be tailored by altering the pH and mixing ratio. Surface potential measurements suggested that the nanochitin-coated lipid droplets adsorbed to the surfaces of the nanocellulose-coated lipid droplets, thereby dominating the overall electrical characteristics of the mixed emulsions. As a result, the mixed emulsions had better stability to coalescence than the single emulsions containing only nanocellulose-coated lipid droplets. Our results suggest that the physicochemical properties, shelf life, and functional performance of Pickering emulsions may be modulated by blending different kinds of particle-stabilized lipid droplets together.

The physicochemical properties of nanoparticles have been tuned via various synthetic methods to improve their diagnostic or curative capability. However, systematic understanding of the relationship between their physicochemical properties and biological effects is still not well established. Particularly, the latent ability of nanomaterials to regulate autophagy has already drawn more attention. In this report, by comparing cellular interactions, uptakes, and autophagic effects of gold nanoparticles with different shapes, we reveal that gold nanoparticles could modulate autophagy in a shape-dependent manner. Western blot assays and confocal images confirm that nanospheres cause more autophagosome accumulation than nanorods, which are highly correlated with the difference in cellular uptakes. With biological TEM, we observe remarkable lysosome swelling and clearly identify the engulfed gold nanoparticles together with undegraded organelles in autolysosomes. Additionally, monitoring of the lysosomal activity and p62 degradation indicates an autophagy flux decrease induced by the impairment of lysosomes after treatment with nanoparticles. Our study not only reveals the effects of nanostructure morphology on autophagy, but also provides an alternative strategy to modulate autophagy, which would contribute to the guidelines for further biomedical applications of various nanomaterials.

Plant-based meat analogs are likely to have different gastrointestinal fates than real meat products due to differences in their compositions and structures. Here, we compared the gastrointestinal fate of ground beef and ground beef analogs using the INFOGEST in vitro digestion model, focusing on differences in microstructure, physicochemical properties, lipid digestion, and protein digestion in different regions of the model gut. The presence of dietary fibers in the beef analogs increased their apparent shear viscosity in the gastrointestinal fluids, which may have inhibited lipid digestion in the small intestine. The proteins in the beef analogs were digested more rapidly in the stomach but less rapidly in the small intestine, which may have been due to differences in protein type (globular soy versus fibrous beef proteins), structural organization, and the presence of dietary fibers in the meat analogs.

The impact of natural emulsifier type on the fabrication, stability, and release attributes of water-in-oil-in-water (W/O/W) emulsions prepared with a high-shear mixer were investigated: gum arabic, high-methoxy pectin, whey protein isolate (WPI), and soy protein isolate (SPI). At 1 wt%, all emulsifiers produced W/O/W emulsions with similar mean droplet diameters (d32 = 23–25 μm). However, less pectin was required to form small droplets than gum arabic, WPI or SPI. The impact of emulsifier type on the transport of small ions between the aqueous phases was then examined by placing iodine and starch in the external and internal water phases, respectively. Iodine turned blue when it came into contact with starch. W/O/W emulsions prepared using proteins (SPI and WPI) were more effective at inhibiting mass transport than those prepared using polysaccharides (gum arabic and pectin). These results are useful for rationalizing the selection of biopolymer emulsifiers for application in double emulsions.

Plant-based milk analogs often contain oil bodies, which are natural colloidal particles comprising of a triglyceride-rich core coated by a phospholipid/protein shell. Hydrophobic nutraceuticals, such as curcumin, can be encapsulated within these oil bodies utilizing a simple pH-driven method. Previously, we loaded curcumin into the oil bodies in soymilk using this approach. Here, we show this method is highly versatile and can be utilized to incorporate curcumin into other plant-based milk analogs (coconut, cashew, almond, and oat milks). Initially, the impact of pH-driven loading on the physicochemical attributes of the milk analogs was investigated. Curcumin bioaccessibility in the milk analogs was then ascertained using a simulated gastrointestinal tract. Curcumin was successfully loaded into all the milk analogs without causing adverse effects on oil body properties or stability. Curcumin had a high encapsulation efficiency (>86%) in all milk analogs, which was attributed to its localization inside the oil bodies. The curcumin-loaded plant-based milks had fairly similar bioaccessibilities (>60%), which were much higher than those seen for a crystalline form of the curcumin (about 5%). The information obtained may be utilized to facilitate the creation of the next-generation of nutritionally fortified plant-based milk analogs.

There is increasing interest in the food industry to develop plant-based emulsifiers for sustainability, ethical, and health reasons. In this study, we showed that stable Pickering emulsions could be fabricated using either cellulose or and chitin nanofibrils, as well as their physical mixtures. These emulsions were highly stable to droplet coalescence during storage, which we attributed to the ability of the nanofibers to adsorb to the oil droplet surfaces and form a thick particulate layer that protected them from coalescence. Moreover, the nanofibers formed a 3D-network in the aqueous phase that prevented the oil droplets from moving, thereby improving their creaming stability. We identified the optimum nanoparticle concentration and nanochitin-to-nanocellulose ratio required to formulate these emulsions. These nanofibers may be useful as edible particle-based emulsifiers for forming more sustainable plant-based food emulsions.

Complex coacervation is a useful approach for creating biopolymer-based colloidal particles for the oral delivery of bioactives, such as nutraceuticals, vitamins, and pharmaceuticals. In this study, we examined the possibility of using anionic ɣ-poly-glutamic acid (PGA) and cationic ɛ-poly- l -lysine (PLL) to form polyelectrolyte complexes. Initially, the formation and properties of the complexes were characterized using visual observations, UV–visible spectrophotometry, microelectrophoresis (ζ-potential), and isothermal titration calorimetry (ITC). The impact of pH, ionic strength, temperature, and polymer ratio on complex formation was examined. The electrostatic complexes formed had a 1:4 mass ratio of polyanion-to-polycation at saturation (pH 7.4). The surface potential and aggregation stability of the complexes was highly dependent on solution pH (2–12), which was attributed to alterations in the electrical characteristics of the two polyelectrolytes. In particular, insoluble complexes were formed under pH conditions where there was a strong electrostatic attraction between the two polyelectrolytes, whereas soluble complexes were formed when there was only a weak attraction. The addition of salt (≥20 mM NaCl) promoted aggregation of the complexes, presumably due to screening of the electrostatic interactions between them. Conversely, temperature (25–90 °C) did not have a major impact on the stability of the complexes. These results may be useful for the design of effective oral delivery systems for bioactive agents in foods and other products.

Fine titanium dioxide (TiO

These is some interest in replacing digestible fats with indigestible ones to decrease the energy-density of foods. The utilization of indigestible oils, however, may have unforeseen nutritional consequences, such as the reduction of vitamin bioavailability. In this study, the impact of an indigestible oil on the bioaccessibility of emulsified vitamin D

Both organic and inorganic nanoparticles are often added to food and beverage products to modify their quality attributes, such as their look, feel, flavor, or shelf life. However, there is still poor understanding of how these nanoparticles behave inside the human gut after ingestion, particularly their impact on macronutrient digestion and vitamin bioavailability. In this study, nanocellulose, nanoemulsion, and titanium dioxide (TiO2) particles were used as examples of functional organic and inorganic nanoparticles, while vitamin D-fortified plant-based milks were used to model food products. The plant-based milks were fortified with this vitamin by mixing them with vitamin-D loaded nanoemulsion droplets. The TiO2 nanoparticles were shown to be most effective at increasing the whiteness of the fortified milk, whereas the nanocellulose ones were most effective at increasing the shear viscosity. Alterations in the physicochemical and structural properties of the nanoparticle-loaded model foods were measured as they passed through a harmonized (INFOGEST) in vitro gastrointestinal tract (GIT). The oil bodies in the plant-based milks were strongly flocculated in the stomach but they were still fully digested in the small intestine. The distribution of the nanoparticles in the intestinal fluids was analyzed by optical and transmission electron microscopy, which showed that they were well dispersed, presumably due to protein-adsorption to their surfaces and the mechanical action of the GIT fluids. The addition of TiO2 or nanocellulose to the fortified milks did not significantly affect lipid digestion or vitamin bioaccessibility. Interestingly, our results showed that the bioaccessibility of vitamin D in the plant-based milk was relatively low (~20%) in all samples analyzed. We hypothesized that this may have been due to aggregation and precipitation of the vitamin-loaded micelles in the presence of other components in the GIT fluids, such as calcium ions. Our results are useful for understanding the impact of different kinds of nanoparticles on the behavior of foods in the gastrointestinal tract.

Arsenic trioxide has achieved great clinical success in the treatment of acute promyelocytic leukemia (APL). However, it is difficult to replicate the success in other cancers, such as solid tumors, in part because of the rapid renal clearance and dose-limiting toxicity. Nanotechnology is expected to overcome these disadvantages through altering its pharmacokinetics and concentrating the drug at the desired sites. Herein, we report a "one-pot" method to develop arsenic-based nanodrugs by in situ coating the as-prepared arsenic nanocomplexes with porous silica shells. This process can be easily reproduced and scaled up because no complicated synthesis and purification steps are involved. This core-shell embedding method endows nanodrugs with high loading capacity (57.9 wt%) and a prolonged pH-responsive releasing profile, which is crucial to increase the drug concentration at tumor sites and improve the drug efficacy. Based on these unique features, the nanodrugs significantly inhibit the growth of solid tumors without adverse side effects. Therefore, we anticipate that the arsenic-based nanodrugs generated by this facile synthetic route may be a powerful and alternative strategy for solid tumor therapy.

Nature-derived nanoparticles are increasingly being explored for their potential to regulate the digestion of ingested lipids. In this study, we examined the impact of emulsifier format (molecular versus particle) on the gastrointestinal fate of vitamin D3-fortified emulsions by measuring their physicochemical properties, microstructure, digestibility, and bioaccessibility using an in vitro human gastrointestinal tract (GIT) model. Nanochitin (NCh) was used as an example of a particle-based (Pickering) emulsifier, whereas Tween 80 (T80) was used as an example of a small molecule surfactant. A series of 2 wt% oil-in-water emulsions containing different initial levels and locations of nanochitin and Tween 80 were prepared: (i) nanochitin-emulsions (0.02 wt% NCh); (ii) Tween 80-emulsions (0.02 wt% T80); (iii) nanochitin-emulsions (0.02 wt% NCh) plus Tween 80 (0.02 wt% T80); and (iv) Tween 80-emulsions (0.02 wt% T80) plus nanochitin (0.02 wt% NCh). The nanochitin-emulsions were much more prone to droplet aggregation within the simulated GIT than the T80-stabilized ones. Lipid digestion was 30% less and vitamin bioaccessibility was 45% less for the nanochitin-emulsions than for the T80-stabilized ones. Adding T80 to the nanochitin-emulsions, increased the rate of lipid digestion, whereas adding nanochitin to the Tween 80-stabilized ones, decreased the rate. The reduction in lipid digestion and bioaccessibility in the emulsions containing nanochitin may have been for a number of reasons: the adsorbed nanochitin layer hindered the ability of lipase to reach the lipid phase; the nanochitin-coated droplets were highly aggregated in the GIT, which reduced the area of lipids accessible to the lipase; and, the cationic nanochitin bound to anionic bile acids, fatty acids, or lipase. Our results suggest that nanochitin slows down lipid digestion, which may be advantageous for developing high-satiety foods, but that it also reduces vitamin bioaccessibility, which would be undesirable from a nutritional perspective.

Anthocyanin-loaded W/O/W emulsions were fabricated using polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier, quillaja saponin as a hydrophilic emulsifier, and gum arabic as an additional biopolymer-based stabilizer. Hydrogenated soybean oil (HSO) was used to create a crystalline lipid phase. The impact of emulsifier, stabilizer, and lipid phase crystallization on emulsion formation, stability, and rheology was investigated. W/O droplets with a solidified oil phase aggregated, leading to an increase in emulsion viscosity. Gum arabic inhibited droplet aggregation and emulsion thickening, presumably by forming a protective coating around the W/O droplets. Conversely, PGPR promoted droplet aggregation, possibly by adsorbing to the fat crystal surfaces and changing their location or interactions. Optimized W/O/W emulsions (2.5% gum arabic, 5% PGPR, and 1% saponin) had a relatively low initial anthocyanin encapsulation efficiency (

Carboxymethylation is a well-known modification process for polysaccharides. To evaluate the biological availability of carboxymethyl, polysaccharide from the seeds of Plantago asiatica L. (PLCP) was carboxymethylated (CM-PLCP) and the immunomodulatory activities of five CM-PLCPs of gradient degree of substitution (DS) from 0.40 to 0.62 were determined on dendritic cells (DCs) in vitro. Compared with DCs treated with PLCP, DCs treated with CM-PLCP of DS0.50, DS0.55, DS0.62, as well as CD86 and CD80, expressed higher levels of MHCII, CD86 and CD80 surface molecules. In addition, the secretion of IL-12p70 and the mRNA of CCR7 and CXCR4 chemokines were increased, while the endocytosis activities were inhibited. Correspondingly, stronger mixed lymphocyte reactions were induced by the DCs treated with the CM-PLCPs. The results showed that carboxymethylation modification of relevant high DS can enhance the DC maturation-inducing function of PLCP, indicating the potential application of carboxymethylated polysaccharide as an immunotherapeutic adjuvant.

Autophagy plays a key role in human health and disease, especially in cancer and neurodegeneration. Many autophagy regulators are developed for therapy. Diverse nanomaterials have been reported to induce autophagy. However, the underlying mechanisms and universal rules remain unclear. Here, for the first time, we show a reliable and general mechanism by which nanoparticles induce autophagy and then successfully modulate autophagy via tuning their dispersity. Various well-designed univariate experiments demonstrate that nanomaterials induce autophagy in a dispersity-dependent manner. Aggregated nanoparticles induce significant autophagic effect in comparison with well-dispersed nanoparticles. As the highly stable nanoparticles may block autophagic degradation in autolysosomes, endocytosis and intracellular accumulation of nanoparticles can be responsible for this interesting phenomenon. Our results suggest dispersity-dependent autophagic effect as a common cellular response to nanoparticles, reveal the relationship between properties of nanoparticles and autophagy and offer a new alternative way to modulate autophagy.