Modulating β-carotene bioaccessibility by controlling oil composition and concentration in edible nanoemulsions

Performance of β-carotene-loaded nanostructured lipid carriers under dynamic in vitro digestion system: Influence of the emulsifier type

A better understanding of how emulsifier type could differently influence the behavior of nanostructured lipid carriers (NLC) under the gastrointestinal digestion process, as well as at the cellular level, is of utmost importance for the NLC-based formulations' optimization and risk assessment in the food field. In this study, NLC composed by fully hydrogenated soybean and high-oleic sunflower oils were prepared using soy lecithin (NLC Lβ) or Tween 80 (NLC Tβ) as an emulsifier. β-Carotene was entrapped within NLC developed as a promising strategy to overcome β-carotene's low bioavailability and stability. The effect of emulsifier type on the digestibility of β-carotene-loaded NLC was evaluated using an in vitro dynamic digestion model mimicking peristalsis motion. The influence of β-carotene-loaded NLC on cell viability was assessed using Caco-2 cells in vitro. NLC Tβ remained stable in the gastric compartment, presenting particle size (PS) similar to the initial NLC (PS: 245.68 and 218.18 nm, respectively), while NLC Lβ showed lower stability (PS > 1000 nm) in stomach and duodenum phases. NLC Tβ also provided high β-carotene protection and delivery capacity (i.e., β-carotene bioaccessibility increased 10-fold). Based on the results of digestion studies, NLC Tβ has shown better physical stability during the passage through the in vitro dynamic gastrointestinal system than NLC Lβ. Moreover, the developed NLC did not compromise cell viability up to 25 µg/mL of β-carotene. Thus, the NLC developed proved to be a biocompatible structure and able to incorporate and protect β-carotene for further food applications. PRACTICAL APPLICATION: The findings of this study hold significant implications for industrial applications in terms of developing nanostructured lipid carriers from natural raw materials widely available and used to produce other lipid-based products in the food industry, as an alternative to synthetic ones. In this respect, the β-carotene-loaded NLC developed in this study would find a great industrial application in the food industry, which is in constant search to develop functional foods capable of increasing the bioavailability of bioactive compounds.

Nutraceutical delivery systems to improve the bioaccessibility and bioavailability of lycopene: A review

Lycopene is a promising biological functional component with various biological activities and excellent pharmacological activities. However, its low water solubility and stability lead to low oral bioavailability, which limits its edible and medicinal research. Then, it is necessary to explore effective methods to protect lycopene from destruction and further exploit its potential benefits. The absorption of lycopene in vivo is affected by solubility, stability, isomer type, emulsifying ability, difficulty in forming micelles in vivo, and interaction with food components. Emulsions, pickering emulsions, micelles, liposomes, bigels, beasds, solid dispersions, microcapsules, nanoparticles, electrospinning and other drug delivery systems can be used as good strategies to improve the stability and bioavailability of lycopene. In this paper, the absorption process of lycopene in vivo and the factors affecting its bioavailability were discussed, and the preparation strategies for improving the stability, bioavailability, and health benefits of lycopene were reviewed, to provide some clues and references for the full utilization of lycopene in the field of health. However, there are still various unresolved mysteries regarding the metabolism of lycopene. The safety and in vivo studies of various preparations should be further explored, and the above technologies also face the challenge of industrial production.

Application of Nanoparticles in Human Nutrition: A Review

Nanotechnology in human nutrition represents an innovative advance in increasing the bioavailability and efficiency of bioactive compounds. This work delves into the multifaceted dietary contributions of nanoparticles (NPs) and their utilization for improving nutrient absorption and ensuring food safety. NPs exhibit exceptional solubility, a significant surface-to-volume ratio, and diameters ranging from 1 to 100 nm, rendering them invaluable for applications such as tissue engineering and drug delivery, as well as elevating food quality. The encapsulation of vitamins, minerals, and antioxidants within NPs introduces an innovative approach to counteract nutritional instabilities and low solubility, promoting human health. Nanoencapsulation methods have included the production of nanocomposites, nanofibers, and nanoemulsions to benefit the delivery of bioactive food compounds. Nutrition-based nanotechnology and nanoceuticals are examined for their economic viability and potential to increase nutrient absorption. Although the advancement of nanotechnology in food demonstrates promising results, some limitations and concerns related to safety and regulation need to be widely discussed in future research. Thus, the potential of nanotechnology could open new paths for applications and significant advances in food, benefiting human nutrition.

Long-Term Stability of Lavandula x intermedia Essential Oil Nanoemulsions: Can the Addition of the Ripening Inhibitor Impact the Biocidal Activity of the Nanoformulations?

In this work, Lavandula x intermedia essential oil (LEO) was encapsulated in lipid-based nanoemulsions (NanoLEO) using the solvent-displacement technique. In order to preserve the colloidal stability of the formulation, LEO was appropriately doped with the incorporation of different levels of a water-insoluble oil used as a ripening inhibitor. All the nanoemulsion samples were evaluated in terms of the impact of the water-insoluble oil on the nanoemulsion formation, physical-chemical properties, and antibacterial effectiveness against E. coli (Gram-negative) and B. cereus (Gram-positive). The presence of the inert oil added benefits to the formulations in terms of appearance, colloidal stability, and loss of volatile components. However, the antimicrobial activity of the nanoemulsions dramatically decreased with the ripening inhibitor addition, probably because it hampered the internalization of the antimicrobial components of LEO within the bacterial cell membranes, thus nullifying the delivery ability of the nanoemulsion formulation. On the contrary, the undoped NanoLEO formulation showed unaltered antibacterial activity in both E. coli and B. cereus up to 40 weeks from the preparation.

α-Tocopherol-loaded multi-layer nanoemulsion using chitosan, and dextran sulfate: Cellular uptake, antioxidant activity, and in vitro bioaccessibility

The potential of multi-layer nanoemulsions (NEs) for improving the cellular uptake, antioxidant activity, and in vitro bioaccessibility of α-tocopherol (ToC) was examined. ToC-loaded multi-layer NEs were prepared using lecithin (primary-NEs, P-NEs), chitosan (secondary-NEs, S-NEs), and dextran sulfate (tertiary-NEs, T-NEs) as wall materials. The bioadhesion, cellular permeability, and uptake of the multi-layer NEs were significantly higher than that of the free coumarin 6 (C6). As a result of cellular uptake, the mean fluorescence intensity of T-NEs was the highest among the three types of multi-layer NEs and was 9.8-fold higher than that of free C6. The cellular antioxidant abilities of P-NEs, S-NEs, and T-NEs were 40, 45, and 50 %, respectively. Multi-layer nanoencapsulation sustains free fatty acid release after digestion. Moreover, the bioavailability of T-NEs exhibited a two-fold increase compared with that of the free ToC. These findings indicate that by multi-layer NEs using a layer-by-layer method, the cellular uptake, in vitro bioaccessibility, and antioxidant activity of ToC can be improved. Furthermore, T-NEs using chitosan and dextran sulfate can potentially enhance the cellular uptake, in vitro bioaccessibility, and antioxidant activity of ToC. These findings would facilitate the application of multi-layer NEs for lipophilic bioactive compounds using biopolymers.

Modulation of physicochemical properties of lipid droplets using soy protein isolate and lactoferrin interfacial coatings

In order to improve the physicochemical stability of soy protein isolate (SPI) emulsion, lactoferrin (LF) was used to modify the interface layer. The stable multilayer emulsion can be formed when the content of lactoferrin is 0.5% at pH 5. The emulsion with good stability was at pH 3-7, and it was also stable to temperature change. The FFAs release of SPI emulsion and LF-SPI emulsion was 103.9% and 103.7%, respectively. The results showed that the lactoferrin layer did not hinder the digestion of oil and the bioaccessibility of carotenoids, but lactoferrin layer improved the physicochemical stability of SPI emulsions. This work provides information valuable in the design of emulsion formulations for applications in the food, pharmaceutical, and personal care industries.

Effect of digestible versus non-digestible citral nanoemulsions on human gut microorganisms: An in vitro digestion study

Essential oil (EO) nanoemulsions have been recently studied due to their antimicrobial properties. Nevertheless, little is known about their possible negative effect against human gut microorganisms during their passage though the gastrointestinal tract. This work studied the effect of digestible (corn oil) or non-digestible (paraffin oil) citral nanoemulsions against specific microorganisms of human microflora under in vitro digestion conditions. The use of a citral lipid carrier (paraffin oil or corn oil) decreased the nanoemulsion particle size and increased its stability after gastric conditions with regards to the pure citral nanoemulsions. Digestible nanoemulsions formulated with corn oil and citral presented a lower bactericidal activity against Lactobacillus acidophilus and Escherichia coli after being subjected to in vitro digestion conditions in comparison to the initial nanoemulsion. However, a non-digestible nanoemulsion formulated with paraffin oil and citral presented a similar antimicrobial activity against L. acidophilus and E. coli to the one of the initial nanoemulsion. This evidences that non-digestible nanoemulsions may entrap the citral in the lipid core and thus retaining its antimicrobial potential during their passage though the gastrointestinal tract. Hence, this work evidences the impact of the lipid carrier digestibility when formulating antimicrobial nanoemulsions on certain intestinal probiotic bacteria.

Impact of the lipid phase composition and state on the in vitro digestibility and chlorophyllin bioaccessibility of W1/O/W2 emulsions into whole milk

Water-in-oil-in-water (W1/O/W2) emulsions offer the potential to deliver hydrophilic bioactive compounds into foods, yet their application remains limited due to their instability. Thus, the impact of lipid phase composition and state on the colloidal stability, in vitro lipid digestibility and chlorophyllin (CHL) bioaccessibility of W1/O/W2 emulsions before and after incorporation into whole milk was studied. Medium-chain triglyceride oil (MCT) was used as a liquid lipid phase and MCT with glyceryl stearate (GS) or pure hydrogenated palm oil (HPO) as gelled lipid phases. The lipid phase composition was crucial to forming W1/O/W2 emulsions. MCT or MCT+GS allowed the successful formation of W1/O/W2 emulsions, being more stable upon gastric conditions those formulated with MCT+GS than pure MCT. In contrast, the use of HPO led to phase separation, which was maintained after the gastric conditions. Regarding their lipid digestibility, W1/O/W2 emulsions formulated with MCT or MCT+GS were fully digested, whereas only 40% of the lipid was digested using HPO. In accordance, the CHL bioaccessibility was higher using MCT or MCT+GS than HPO. When co-digested with whole milk, the colloidal stability and lipid digestibility of the W1/O/W2 emulsions with MCT or MCT+GS were not altered, whereas the W1/O/W2 emulsion-HPO showed enhanced colloidal stability and lipid digestibility (57.71 ± 3.06%), due to the surface-active properties of milk protein. The present study provides useful information to develop stable functional foods enriched with hydrophilic bioactive compounds by using W1/O/W2 emulsions.

Influence of 1,3-diacylglycerol on physicochemical and digestion properties of nanoemulsions and its enhancement of encapsulation and bioaccessibility of hydrophobic nobiletin

Lipid-based delivery systems are commonly used to encapsulate hydrophobic bioactive compounds for enhancing their bioaccessibility and bioavailability, especially for triacylglycerol (TAG) oil-based delivery systems. However, studies on the development of 1,3-diacylglycerol (DAG) oil-based delivery systems are rather limited. Herein, the influence of 1,3-DAG oil as a carrier oil on the properties of nanoemulsions and the bioaccessibility of encapsulated hydrophobic nobiletin (NOB) were investigated. High-purity 1,3-DAG (over 93% pure) was prepared by a combination of enzymatic esterification and ethanol crystallization. 1,3-DAG oil as a carrier oil could be used to formulate nanoemulsions with smaller droplet size, narrower size distribution and similar stability compared to TAG oil. Importantly, 1,3-DAG oil could efficiently encapsulate high-loading NOB (1.45 mg g-1) in nanoemulsions and significantly improve the bioaccessibility of NOB (above 80%), which is attributable to its massive lipolysis and higher encapsulation capacity than TAG oil. Moreover, the addition of the 1,3-DAG component in TAG oil significantly improved the properties of nanoemulsions and the loading and bioaccessibility of NOB, especially as the 1,3-DAG content was not less than 50%. The structure of lipids (DAG versus TAG) influenced the nanoemulsion properties and the bioaccessibility of encapsulated NOB. Based on the good properties of 1,3-DAG oil coupled with its health benefits, 1,3-DAG oil-based nanoemulsion delivery systems have great prospects for improving and extending emulsion properties and bioactivity as well as bioaccessibility enhancement.

Polysaccharide-based structured lipid carriers for the delivery of curcumin: An in vitro digestion study

The present work aimed at studying the in vitro digestion fate of κ-carrageenan (KC) or agar (AG) emulsion gels (EG), and KC oil-filled aerogels (OAG) in terms of their structural changes, lipolysis kinetics and curcumin bioaccessibility. On the one hand, both EG and aerogels showed large (70-200 µm) and heterogeneous particles after gastric conditions, indicating the release of bulk oil and gelled material. Nonetheless, this material release in the stomach phase was lower in the case of EG-AG and OAG-KC compared to EG-KC. After small intestinal conditions, EG and oil-filled aerogels presented a wide range of particle sizes probably due to the presence of undigested lipid material, gelled structures, as well as lipid digestion products. For the most part, adding curcumin to the structures' lipid phase did not cause of the structural modifications that occurred at the different in vitro digestion phases. On the other hand, the lipolysis kinetics was different depending on the type of structure. Amongst emulsion-gels, those formulated with κ-carrageenan presented a slower and lower lipolysis kinetics compared to those formulated with agar, which could be attributed to their higher initial hardness. Overall, the addition of curcumin in the lipid phase decreased the lipolysis in all the structures, which evidenced its interference in the lipid digestion process. The curcumin bioaccessibility reached high values (≈ 100 %) for all the studied structures, presenting a high solubility in intestinal fluids. This work unravels the implications of microstructural changes of emulsion-gels and oil-filled aerogels during digestion and their impact on their digestibility and subsequent functionality.

Oral bioavailability of bioactive compounds; modulating factors, in vitro analysis methods, and enhancing strategies

Foods are complex biosystems made up of a wide variety of compounds. Some of them, such as nutrients and bioactive compounds (bioactives), contribute to supporting body functions and bring important health benefits; others, such as food additives, are involved in processing techniques and contribute to improving sensory attributes and ensuring food safety. Also, there are antinutrients in foods that affect food bioefficiency and contaminants that increase the risk of toxicity. The bioefficiency of food is evaluated with bioavailability which represents the amount of nutrients or bioactives from the consumed food reaching the organs and tissues where they exert their biological activity. Oral bioavailability is the result of some physicochemical and biological processes in which food is involved such as liberation, absorption, distribution, metabolism, and elimination (LADME). In this paper, a general presentation of the factors influencing oral bioavailability of nutrients and bioactives as well as the in vitro techniques for evaluating bioaccessibility and is provided. In this context, a critical analysis of the effects of physiological factors related to the characteristics of the gastrointestinal tract (GIT) on oral bioavailability is discussed, such as pH, chemical composition, volumes of gastrointestinal (GI) fluids, transit time, enzymatic activity, mechanical processes, and so on, and the pharmacokinetics factors including BAC and solubility of bioactives, their transport across the cell membrane, their biodistribution and metabolism. The impact of matrix and food processing on the BAC of bioactives is also explained. The researchers' recent concerns for improving oral bioavailability of nutrients and food bioactives using both traditional techniques, for example, thermal treatments, mechanical processes, soaking, germination and fermentation, as well as food nanotechnologies, such as loading of bioactives in different colloidal delivery systems (CDSs), is also highlighted.

Emulsion-Based Delivery Systems to Enhance the Functionality of Bioactive Compounds: Towards the Use of Ingredients from Natural, Sustainable Sources

In recent years, the trend in the population towards consuming more natural and sustainable foods has increased significantly. This claim has led to the search for new sources of bioactive compounds and extraction methods that have less impact on the environment. Moreover, the formulation of systems to protect these compounds is also focusing on the use of ingredients of natural origin. This article reviews novel, natural alternative sources of bioactive compounds with a positive impact on sustainability. In addition, it also contains information on the most recent studies based on the use of natural (especially from plants) emulsifiers in the design of emulsion-based delivery systems to protect bioactive compounds. The properties of these natural-based emulsion-delivery systems, as well as their functionality, including in vitro and in vivo studies, are also discussed. This review provides relevant information on the latest advances in the development of emulsion delivery systems based on ingredients from sustainable natural sources.

Encapsulation of lycopene into electrospun nanofibers from whey protein isolate-Tricholoma lobayense polysaccharide complex stabilized emulsions: Structural characterization, storage stability, in vitro release, and cellular evaluation

In this study, lycopene-loaded nanofibers were successfully fabricated by electrospinning of oil-in-water (O/W) emulsions stabilized by whey protein isolate-polysaccharide TLH-3 (WPI-TLH-3) complexes. The lycopene encapsulated in the emulsion-based nanofibers exhibited enhanced photostability and thermostability, and achieved improved targeted small intestine-specific release. The release of lycopene from the nanofibers followed Fickian diffusion mechanism in simulated gastric fluid (SGF) and first-order model in simulated intestinal fluid (SIF) with the enhanced release rates. The bioaccessibility and cellular uptake efficiency of lycopene in micelles by Caco-2 cells after in vitro digestion were significantly improved. The intestinal membrane permeability and transmembrane transport efficiency of lycopene in micelles across Caco-2 cells monolayer were greatly elevated, thus promoting the effective absorption and intracellular antioxidant activity of lycopene. This work opens a potential approach for electrospinning of emulsions stabilized by protein-polysaccharide complexes as a novel delivery system for liposoluble nutrients with enhanced bioavailability in functional food industries.

Digestion behavior, in vitro and in vivo bioavailability of cannabidiol in emulsions stabilized by whey protein-maltodextrin conjugate: Impact of carrier oil

An emulsion delivery system may be affected significantly by oil phase composition in terms of digestion behavior and bioavailability of the delivered substance. In this study, emulsions loaded with cannabidiol (CBD) were prepared with medium chain triglyceride (MCT), long chain triglyceride (LCT) or MCT/LCT(1:1) as carrier oil and whey protein-maltodextrin conjugate as emulsifier, and the digestion behavior of emulsion and bioavailability of CBD were assessed in vitro and in vivo. The particle size of emulsions throughout the in vitro digestion process was in the order of MCT < MCT/LCT < LCT, and three emulsions showed consistent particle size changes: stable in oral phase, sharply increased in gastric phase, and decreased in small intestine. After intestinal digestion, about 90% of free fatty acids (FFA) was released in MCT emulsion, followed by MCT/LCT (76%) and then LCT (45%). CBD was degraded during gastrointestinal digestion and the transformation stability of CBD in oil phase was in the order of LCT > MCT/LCT > MCT. Although CBD had higher bioaccessibility in MCT and MCT/LCT emulsions, the bioavailability of CBD in LCT was the highest (43%), followed by MCT/LCT (39%), MCT (33%). In vivo pharmacokinetic study showed that MCT/LCT and LCT were more favorable for CBD transport and absorption. The results may provide useful information for the construction of delivery systems, protecting CBD molecules, and improving their bioavailability.

Polysaccharide-based porous biopolymers for enhanced bioaccessibility and bioavailability of bioactive food compounds: Challenges, advances, and opportunities

Bioactive food compounds, such as lycopene, curcumin, phytosterols, and resveratrol, have received great attention due to their potential health benefits. However, these bioactive compounds (BCs) have poor chemical stability during processing and low bioavailability after consumption. Several delivery systems have been proposed for enhancing their stability and bioavailability. Among these methods, porous biopolymers have emerged as alternative encapsulation materials, as they have superior properties like high surface area, porosity, and tunable surface chemistry to entrap BCs. This reduces the crystallinity (especially for the lipophilic ones) and particle size, and in turn, increases solubilization and bioavailability. Also, loading BCs into the porous matrix can protect them against environmental stresses such as light, heat, oxygen, and pH. This review introduces polysaccharide-based porous biopolymers for improving the bioaccessibility/bioavailability of bioactive food compounds and discusses their recent applications in the food industry. First, bioaccessibility and bioavailability are described with a special emphasis on the factors affecting them. Then, porous biopolymer fabrication methods, including supercritical carbon dioxide (SC-CO₂ ) drying, freeze-drying, and electrospinning and electrospraying, are thoroughly discussed. Finally, common polysaccharide-based biopolymers (i.e., starch, nanocellulose, alginate, and pectin) used for generating porous materials are reviewed, and their current and potential future food applications are critically discussed.

Impact of emulsifiers for the nanoencapsulation with maltodextrin of cannabis oil by spray drying on the physicochemical properties and bioaccessibility of cannabinoids

Our study aimed to investigate the impact of various emulsifiers, namely whey protein isolate (WPI), soy protein isolate (SPI), and Tween 80 (Tw), on their ability to encapsulate cannabis oil with maltodextrin as the wall material. The physicochemical properties of the powder, the stability of the cannabinoids, and their bioaccessibility during static in vitro digestion were examined. The average diameter of fat globules in liquid nanoemulsions was 170, 259, and 95 nm for WPI, SPI, and Tw, respectively. The encapsulation efficiency was high for protein emulsifiers (>95%) compared to Tw (∼16%). Upon powder reconstitution in water, the emulsified fat droplets remained stable for WPI (176 nm); however, higher fat globule size (diameters of 346 nm and 210 nm) was observed for SPI and Tw powders, respectively. All oil powders had high solubility (>97%). The peroxide value (PV) showed nearly a fourfold increase for the oil extracted from the powder than the initial PV of bulk oil (5.2 mEq). However, UPLC-TUV analysis of the main cannabinoids (CBD, THC, and CBN) indicated that there is no significant difference between the various formulations and the bulk oil, except for lower Tw. The in vitro digestion model results showed higher bioaccessibility of the cannabinoids for Tw (∼53%) than for proteins (WPI ∼ 7% and SPI ∼ 10%). These findings suggest that the emulsifiers used for spray drying nanoencapsulation of cannabis oil have an impact on the encapsulation efficiency and cannabinoid bioaccessibility, highlighting the importance of choosing adequate emulsifiying agents for their optimal oral delivery.

Mechanisms of carotenoid intestinal absorption and the regulation of dietary lipids: lipid transporter-mediated transintestinal epithelial pathways

Dietary lipids are key ingredients during cooking, processing, and seasoning of carotenoid-rich fruits and vegetables, playing vitals in affecting the absorption and utilization of carotenoids for achieving their health benefits. Besides, dietary lipids have also been extensively studied to construct various delivery systems for carotenoids, such as micro/nanoparticles, micro/nanoemulsions, and liposomes. Currently, the efficacies of these techniques on improving carotenoid bioavailability are often evaluated using the micellization rate or "bioaccessibility" based on in vitro models. However, recent studies have found that dietary lipids may also affect the carotenoid uptake via intestinal epithelial cells and the efflux of intracellular chyle particles via lipid transporters. An increasing number of studies reveal the varied impact of different dietary lipids on the absorption of different carotenoids and some lipids may even have an inhibitory effect. Consequently, it is necessary to clarify the relationship between the addition of dietary lipids and the intestinal absorption of carotenoid to fully understand the role of lipids during this process. This paper first introduces the intestinal absorption mechanism of carotenoids, including the effect of bile salts and lipases on mixed micelles, the types and regulation of lipid transporters, intracellular metabolizing enzymes, and the efflux process of chyle particles. Then, the regulatory mechanism of dietary lipids during intestinal carotenoid absorption is further discussed. Finally, the importance of selecting the dietary lipids for the absorption and utilization of different carotenoids and the design of an efficient delivery carrier are emphasized. This review provides suggestions for precise dietary carotenoid supplementation and offere an important reference for constructing efficient transport carriers for liposoluble nutrients.

Construction of lipid-biomacromolecular compounds for loading and delivery of carotenoids: Preparation methods, structural properties, and absorption-enhancing mechanisms

Due to the unstable chemical properties and poor water solubility of carotenoids, their processing adaptation and oral bioavailability are poor, limiting their application in hydrophilic food systems. Lipid-biomacromolecular compounds can be excellent carriers for carotenoid delivery by taking full advantage of the solubilization of lipids to non-polar nutrients and the water dispersion and gastrointestinal controlled release properties of biomacromolecules. This paper reviewed the research progress of lipid-biomacromolecular compounds as encapsulation and delivery carriers of carotenoids and summarized the material selection and preparation methods for biomacromolecular compounds. By considering the interaction between the two, this paper briefly discussed the effect of these compounds on carotenoid water solubility, stability, and bioavailability, emphasizing their delivery effect on carotenoids. Finally, various challenges and future trends of lipid-biomacromolecular compounds as carotenoid delivery carriers were discussed, providing new insight into efficient loading and delivery of carotenoids.

Nano-enabled plant-based colloidal delivery systems for bioactive agents in foods: Design, formulation, and application

Consumers are becoming increasingly aware of the impact of their dietary choices on the environment, animal welfare, and health, which is causing many of them to adopt more plant-based diets. For this reason, many sectors of the food industry are reformulating their products to contain more plant-based ingredients. This article describes recent research on the formation and application of nano-enabled colloidal delivery systems formulated from plant-based ingredients, such as polysaccharides, proteins, lipids, and phospholipids. These delivery systems include nanoemulsions, solid lipid nanoparticles, nanoliposomes, nanophytosomes, and biopolymer nanoparticles. The composition, size, structure, and charge of the particles in these delivery systems can be manipulated to create novel or improved functionalities, such as improved robustness, higher optical clarity, controlled release, and increased bioavailability. There have been major advances in the design, assembly, and application of plant-based edible nanoparticles within the food industry over the past decade or so. As a result, there are now a wide range of different options available for creating delivery systems for specific applications. In the future, it will be important to establish whether these formulations can be produced using economically viable methods and provide the desired functionality in real-life applications.

Effect of microcrystalline cellulose under different hydrolysis durations on the stability of thyme oil emulsion

The thyme oil emulsion was prepared using a novel type of nanocellulose obtained under different hydrolysis durations. The effect of different cellulose structures on interfacial adsorption properties of emulsion and loading efficiency of thyme oil were analyzed. The results showed that the cellulose particles became more homogeneous and hydrophilic after hydrolysis duration for 10 h. The loading efficiency of thyme oil for all emulsions reached about 80%. The retention rate of thyme oil decreased during the storage period, and rising temperatures will exacerbate the loss of thyme oil. Compared to Hd2, emulsions stabilized by Hd10 exhibited better stability and higher retention at all storage conditions. Cellulose emulsion can increase the dispersion and improve the stability of thyme oil. A smaller cellulose particle could make the emulsion become more stable. The experimental results confirmed that cellulose can be used as a stabilizer to encapsulate and transport hydrophobic active ingredient. PRACTICAL APPLICATION: The study results demonstrated that the emulsion transport system was developed using cellulose nanoparticles prepared by hydrolysis. The system can be used to load hydrophobic active substances (active peptides, curcumin, β-carotene, essential oils, etc.). It can protect the active substance from environmental damage, enhance water solubility and stability, and improve the bioavailability of the active substance.

Fabrication of nanoemulsion delivery system with high bioaccessibility of carotenoids from Lycium barbarum by spontaneous emulsification

The interest in incorporating carotenoids into foods and beverages is growing due to their potential health benefits. However, the poor water solubility and low bioavailability of carotenoids are still challenges in food application. This work aimed to study the influence of system composition and preparation conditions on the physical properties of carotenoids‐loaded nanoemulsions prepared by spontaneous emulsification. Furthermore, the bioaccessibility of carotenoids in the nanoemulsions was evaluated. The nanoemulsions with the smallest droplet size were produced when the ratio of Span 80:Tween 80 was 1.5:8.5. The droplet size increased slightly with the increase of organic phase content (24%–40%). The droplet size decreased gradually with the increase of stirring speed (200–1000 rpm (revolutions per minute)). The ratio of mixed surfactants and surfactant‐to‐oil ratio (SOR) had an appreciable impact on the droplet size. Carotenoids‐loaded nanoemulsions with small mean droplet size (d < 50 nm) could be prepared with the optimized conditions. The initial digestion rate decreased as the SOR increased. The bioaccessibility could reach up to about 80% at SOR=2–5 in vitro digestion. These results have important implications for the design of effective delivery systems to encapsulate carotenoids and other lipophilic bioactive components in food applications.

Nutraceutical potential of industrial hemp (Cannabis sativa L.) extracts: physicochemical stability and bioaccessibility of cannabidiol (CBD) nanoemulsions

Cannabidiol (CBD) is one of the most promising functional food ingredients, which displays a number of health benefits. However, its low solubility and bioavailability impede its applications in functional foods. Herein, we developed a food-grade CBD nanoemulsion system using medium chain triacylglycerides (MCT), canola oil (CO), or hemp seed oil (HSO) as the carrier oil to compare the physicochemical stability and bioaccessibility of CBD. Encouragingly, all formulations were well maintained for 90 days under the tested temperatures (4, 25 and 37 °C) and pH values (3.5 and 7.0). Quantitative analysis of CBD during storage using high performance liquid chromatography revealed that the light exposure and acidity of the solution are two important factors affecting the chemical stability of CBD. Moreover, improved bioaccessibility of CBD in all three nanoemulsion formulations compared to that of bulk oil forms was confirmed, and the long chain triacylglyceride (LCT)-based nanoemulsion was superior to the MCT-based counterpart.

Vitamin A fortification: Recent advances in encapsulation technologies

Vitamin A is an essential micronutrient whose deficiency is still a major health concern in many regions of the world. It plays an essential role in human growth and development, immunity, and vision, but may also help prevent several other chronic diseases. The total amount of vitamin A in the human diet often falls below the recommended dietary allowance of approximately 900-1000 μ $ \umu $ g/day for a healthy adult. Moreover, a significant proportion of vitamin A may be degraded during food processing, storage, and distribution, thereby reducing its bioactivity. Finally, the vitamin A in some foods has a relatively low bioavailability, which further reduces its efficacy. The World Health Organization has recommended fortification of foods and beverages as a safe and cost-effective means of addressing vitamin A deficiency. However, there are several factors that must be overcome before effective fortified foods can be developed, including the low solubility, chemical stability, and bioavailability of this oil-soluble vitamin. Consequently, strategies are required to evenly disperse the vitamin throughout food matrices, to inhibit its chemical degradation, to avoid any adverse interactions with any other food components, to ensure the food is palatable, and to increase its bioavailability. In this review article, we discuss the chemical, physical, and nutritional attributes of vitamin A, its main dietary sources, the factors contributing to its current deficiency, and various strategies to address these deficiencies, including diet diversification, biofortification, and food fortification.

An Edible Oil Enriched with Lycopene from Pink Guava (Psidium guajava L.) Using Different Mechanical Treatments

According to the regulations of the United States Food and Drug Administration (FDA), organic solvents should be limited in pharmaceutical and food products due to their inherent toxicity. For this reason, this short paper proposes different mechanical treatments to extract lycopene without organic solvents to produce an edible sunflower oil (SFO) enriched with lycopene from fresh pink guavas (Psidium guajava L.) (FPGs). The methodology involves the use of SFO and a combination of mechanical treatments: a waring blender (WB), WB+ high-shear mixing (HSM) and WB+ ultrafine friction grinding (UFFG). The solid:solvent (FPG:SFO) ratios used in all the techniques were 1:5, 1:10 and 1:20. The results from optical microscopy and UV–vis spectroscopy showed a correlation between the concentration of lycopene in SFO, vegetable tissue diameters and FPG:SFO ratio. The highest lycopene concentration, 18.215 ± 1.834 mg/g FPG, was achieved in WB + UFFG with an FPG:SFO ratio of 1:20. The yield of this treatment was 66% in comparison to the conventional extraction method. The maximal lycopene concentration achieved in this work was significantly higher than the values reported by other authors, using high-pressure homogenization for tomato peel and several solvents such as water, SFO, ethyl lactate and acetone.

Influence of interfacial characteristics and antioxidant polarity on the chemical stability of β-carotene in emulsions prepared using non-ionic surfactant blends

To evaluate the effects of characteristics of the interfacial region and physical location of antioxidants on the chemical stability of β-carotene in emulsions, β-carotene-loaded emulsions were prepared with the blends of surfactants with different hydrophilic head sizes (ethylene oxide (EO) unit number). In addition, antioxidants having the different solubilities, tert-butylhydroquinone (TBHQ) and lauryl gallate as lipophilic and amphiphilic antioxidants, respectively, were incorporated into emulsions. Decrease in the average EO unit number at interfacial region by surfactant blending did not affect the stability of β-carotene in emulsions at neutral pH but it had a positive effect on the β-carotene stability at acidic pH. Decrease in the average EO unit number at interfacial region reduced the ability of antioxidants, regardless of their polarity, to protect β-carotene in emulsions at neutral and acidic pH. TBHQ was more effective in retarding β-carotene degradation than lauryl gallate, independent of the interfacial composition and surfactant concentration.

Micelle separation conditions based on particle size strongly affect carotenoid bioaccessibility assessment from juices after in vitro digestion

For assessing the carotenoid bioaccessibility during in vitro digestion, obtaining the micelle fraction that can diffuse through the mucin layer according to the particle size is an important step. However, the accuracy of the various approaches to obtaining the right fraction of micelles described in literature has not been investigated. In many studies the reported bioaccessible fraction might therefore be over- or underestimating the real bioaccessibility. The present study aimed to fill this gap and give approaches to get accurate data on the bioaccessible fraction from samples with different properties. Results illustrated that optimizing the centrifugal speed and duration of the digesta are essential in obtaining the micelle fraction. Different digesta have different optimum centrifugal parameters to obtain the bioaccessible fraction. 6,000 rpm and 40 min was selected as the optimum centrifugal parameter for combined juice (CJ). 6,000 rpm and 60 min was the optimum centrifugal parameter for CJ with oil, and CJ with emulsion using non-ionic emulsifier. 8,000 rpm and 20 min was the optimum centrifugal parameter for CJ with emulsion using ionic emulsifier. Polygalacturonanase (PG)-digested systems required higher centrifugal speed (10,000 rpm) compared with CJ-based systems (6,000 rpm or 8,000 rpm). A prediction model to determine the optimal centrifugation speed/time from the properties of the intestinal digesta was developed. Sample preparation conditions strongly affect carotenoid bioaccessibility assessment from juices during in vitro digestion. Based on these results, it is highly recommended to perform an optimized preparation procedure for bioaccessible fraction prior to carotenoid bioaccessibility analysis.

Effects of dietary fats on the bioaccessibility and bioavailability of carotenoids: a systematic review and meta-analysis of in vitro studies and randomized controlled trials

CONTEXT

Dietary fats are one of the well-known stimulators of carotenoid absorption, but the effects of the quantity and the type of dietary fats on carotenoid absorption have not yet been studied systematically.

OBJECTIVE

This review aimed to analyze data from both in vitro studies and randomized controlled trials (RCTs) to examine the effects of dietary fats on the bioaccessibility and bioavailability of carotenoids.

DATA SOURCES

A systematic search of 5 databases (Scopus, PubMed, Embase, CINAHL and the Cochrane Library) was conducted.

STUDY SELECTION

In vitro studies and RCTs were selected according to the PICOS criteria and were reviewed independently by 2 investigators.

DATE EXTRACTION

Key study characteristics from the eligible in vitro studies and RCTs were extracted independently by 2 investigators using a standardized table.

RESULTS

A total of 27 in vitro studies and 12 RCTs were included. The meta-regression of in vitro studies showed that the bioaccessibility of carotenoids, except for lycopene, was positively associated with the concentration of dietary fats. The meta-analysis of RCTs showed that the bioavailability of carotenoids was enhanced when a higher quantity of dietary fats was co-consumed. Moreover, fats rich in unsaturated fatty acids resulted in greater improvement in carotenoid bioavailability (SMD 0.90; 95%CI, 0.69-1.11) as compared with fats rich in saturated fatty acids (SMD 0.27; 95%CI, 0.08-0.47).

CONCLUSIONS

Co-consuming dietary fats, particularly those rich in unsaturated fatty acids, with carotenoid-rich foods can improve the absorption of carotenoids.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42020188539.

Tailoring the properties of double-crosslinked emulsion gels using structural design principles: Physical characteristics, stability, and delivery of lycopene

Lycopene is claimed to have numerous physiological benefits, but its poor water solubility, chemical instability, and low bioavailability limit its application in functional foods and health care products. In this study, lycopene-loaded emulsions containing oil droplets with different interfacial structures were prepared and then cross-linked using transglutaminase (TG) and/or calcium ions (Ca²⁺) to form emulsion gels. The oil droplets were first coated by interfacial layers comprised of whey protein isolate (WPI) and sodium alginate (SA). During emulsion preparation, the SA was added either before or after homogenization to create complex or layer-by-layer coatings, respectively. Subsequently, TG and Ca²⁺ were used to cross-link WPI and SA to form emulsion gels. The results show that double-crosslinking increased the gel strength and viscosity of the emulsion gels. The layer-by-layer emulsion gels were stronger and more viscous than the complex ones. The photochemical and gastrointestinal stability of lycopene encapsulated within the emulsion gels was higher than that of free lycopene. An MTT toxicity test showed that the emulsion gels exhibited no cytotoxicity to Caco-2 cells. The lycopene-loaded emulsion gels exhibited stronger anti-inflammatory activity on the Caco-2 cells than the control. In addition, the absorption of lycopene by the Caco-2 cells increased after encapsulation. This study provides a new approach of preparing edible soft materials to enhance the application of hydrophobic bioactives (like lycopene) in functional foods.

Enhancing bioaccessibility and bioavailability of carotenoids using emulsion-based delivery systems

The consumption of foods rich in antioxidants, vitamins, minerals including carotenoids etc. can boost the immune system to help fight off various infections including SARS- CoV 2 and other viruses. Carotenoids have been gaining attention particularly in food and pharmaceutical industries owing to their diverse functions including their role as pro-vitamin A activity, potent antioxidant properties, and quenching of reactive oxygen (ROS), such as singlet oxygen and lipid peroxides within the lipid bilayer of the cell membrane. Nevertheless, carotenoids being lipophilic, have poor solubility in aqueous medium and are also chemically instable. They are susceptible to degrade under stimuli environmental conditions during food processing, storage and gastrointestinal passage. They also exhibit poor oral bioavailability, thus, their applications in aqueous-based foods are limited. As a consequent, suitable delivery systems including colloids-based are needed to enhance the solubility, stability and bioavailability of carotenoids. This review presents challenges of incorporation and delivery of carotenoids focusing on stability and factors affecting bioavailability. Furthermore, designed factors impacting bioaccessibility and bioavailability of carotenoids using emulsion-based delivery systems are explicitly explained. Each delivery system exhibits its own advantages and disadvantages; thus, the delivery systems should be designed based on their targets and their further applications.

Fabrication and characterization of β-carotene emulsions stabilized by soy oleosin and lecithin mixtures with a composition mimicking natural soy oleosomes

Natural soy oleosomes are known to have a remarkable stability, given the advantage of their sophisticated membrane. The aim of the present study is to examine the concept of fabricating a β-carotene emulsion stabilized by soy oleosin (OLE) and lecithin (LEC) mixtures mimicking the membrane composition of soy oleosomes while providing preferable stability and bioaccessibility. For this, the fabricated emulsion was characterized in terms of droplet size distribution, and emulsion structure, stability and digestion (release and absorption of lipophilic β-carotene). Compared to SPI/LEC (10 : 1) stabilized emulsions, the OLE/LEC (10 : 1) mixture stabilized emulsion exhibited the highest emulsifying activity index (EAI) and emulsifying stability index (ESI) values, and higher encapsulation efficiency. Results show that the β-carotene emulsion stabilized by OLE and LEC mixtures at the ratio of 10 : 1 (w/w) has the most uniform droplet distribution and highest stability. The in vitro gastrointestinal digestion test revealed that the β-carotene emulsion stabilized by OLE and LEC mixtures was digested more rapidly than the emulsion stabilized by soy protein isolate (SPI) and LEC mixtures. In turn, the bioaccessibility and cellular uptake of β-carotene were enhanced, resulting in a higher absorption, a desirable feature of nutrition delivery systems. Our results demonstrated a promising way to fabricate emulsions mimicking natural soy oleosomes.

Nanoencapsulation of lutein within lipid-based delivery systems: Characterization and comparison of zein peptide stabilized nano-emulsion, solid lipid nanoparticle, and nano-structured lipid carrier

Three lipid-based carriers encapsulating lutein, nano-emulsion (NE), solid lipid nanoparticle (SLN), and nano-structured lipid carrier (NLC), were developed from zein peptides hydrolyzed by trypsin (TZP) and flavourzyme (FZP) as stabilizers. The physiochemical properties of FZP and TZP were evaluated. The particle size, potential, microstructure, environmental stability, rheological properties, in vitro digestion stability, and bioavailability of the lutein-loaded NE, SLN, and NLC were compared. The results showed that the surface hydrophobicity of TZP was higher than that of FZP. Except for the SLN, most samples were stable against droplet aggregation during storage, and carriers stabilized by TZP exhibited more favorable storage stabilities than those prepared from FZP. All the samples presented characteristics of fluid with good fluidity. The bioavailability of lutein was between 42.61% and 62.81%. In summary, these results provide valuable insights into the design of lipid-based delivery systems for fat-soluble biologically active compounds using zein peptides as stabilizers.

Nanoemulsions for Enhancement of Curcumin Bioavailability and Their Safety Evaluation: Effect of Emulsifier Type

This work aimed at evaluating the effects of different emulsifiers on curcumin-loaded nanoemulsions’ behavior during digestion, its safety and absorption, to develop nanoemulsions that provide safety and improved curcumin functionality. Nanoemulsions (NEs) were produced using two bio-based (lecithin (LEC) and rhamnolipids (RHAM)) and one synthetic (Tween^®80 (TWE)) emulsifier at similar concentrations. Different NEs were subjected to in vitro digestion. The cytotoxicity and permeability tests were performed in Caco-2 cells. NE_TWE were stable during all phases of in vitro digestion, whereas NE_LEC and NE_RHAM were found to be unstable from the gastric phase. NE_TWE showed 100% of free fatty acids released, followed by NE_RHAM and NE_LEC. Curcumin’s bioaccessibility and stability increased in the following order: NE_LEC > NE_RHAM > NE_TWE. NE_LEC and NE_TWE did not show cytotoxic effects in any of the concentrations tested, while NE_RHAM presented high cytotoxicity in all concentrations tested. The apparent permeability coefficients were determined for NE_LEC and NE_TWE; however, the results were not statistically different. These results showed that the emulsifier used has a high impact on nanoemulsions’ behavior under the digestion process and on their cytotoxicity. This work contributed to the state-of-the-art’s progress on the development of safer curcumin delivery systems with improved functionality, particularly regarding the proper selection of ingredients to produce said systems.

Influence of oil matrixes on stability, antioxidant activity, bioaccessibility and bioavailability of astaxanthin ester

BACKGROUND

Astaxanthin ester (Asta-E) is used as functional nutraceuticals in many food products. Unfortunately, Asta-E utilization is currently limited owing to its chemical instability and low bioavailability. The purpose of this study is to investigate the promotion effect of oil matrixes on the stability, antioxidant activity, bioaccessibility and bioavailability of Asta-E.

RESULTS

The results showed that the stability of Asta-E in six oil matrixes was improved. Based on the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity experiment, the antioxidant activity of Asta-E was positively correlated with the degree of unsaturation of the oil matrixes, but not with the side chain length. The in vitro gastrointestinal tract (GIT) simulation model and in vivo experiment using mice were also employed to investigate the digestion and absorption characteristics of Asta-E in various oil matrixes. The results demonstrated that the bioaccessibility and bioavailability of Asta-E increased with the increase of fatty acid chain length of oil matrixes (triglyceride oleate > triglyceride caprylate > triglyceride butyrate), as well as with the decrease of unsaturation degree (olive oil > corn oil > fish oil).

CONCLUSION

Monounsaturated fatty acids (MUFA) and long-chain triglyceride (LCT) in an oil matrix were the factors that could efficiently improve the bioavailability of Asta-E. Moreover, the size of the mixed micelles of Asta-E during digestion was the main factor influencing the bioaccessibility of Asta-E. This study provides references for the design of suitable oil matrixes for Asta-E. © 2020 Society of Chemical Industry.

Food-Grade Titanium Dioxide Particles Decreased the Bioaccessibility of Vitamin D3 in the Simulated Human Gastrointestinal Tract

Food-grade titanium dioxide (E171) particles, as a "whiteness" additive, are often co-ingested with lipid-rich foods. Therefore, we explored the impact of E171 on lipid digestion and vitamin D₃ (VD₃) bioaccessibility encapsulated within oil-in-water emulsions in a simulated human gastrointestinal tract (GIT) model. VD₃ bioaccessibility significantly decreased from 80 to 74% when raising E171 from 0 to 0.5 wt %. The extent of lipid digestion was reduced by E171 addition in a dose-dependent manner. VD₃ bioaccessibility was positively correlated with the final amount of free fatty acids (FFAs) produced by lipid digestion (R² = 0.95), suggesting that the reduction in VD₃ bioaccessibility was due to the inhibition of lipid digestion by E171. Further experiments showed that E171 interacted with lipase and calcium ions, thereby interfering with lipid digestion. The findings of this study enhance our understanding toward the potential impact of E171 on the nutritional attributes of foods for human digestion health.

Fate of β-Carotene within Loaded Delivery Systems in Food: State of Knowledge

Nanotechnology has opened new opportunities for delivering bioactive agents. Their physiochemical characteristics, i.e., small size, high surface area, unique composition, biocompatibility and biodegradability, make these nanomaterials an attractive tool for β-carotene delivery. Delivering β-carotene through nanoparticles does not only improve its bioavailability/bioaccumulation in target tissues, but also lessens its sensitivity against environmental factors during processing. Regardless of these benefits, nanocarriers have some limitations, such as variations in sensory quality, modification of the food matrix, increasing costs, as well as limited consumer acceptance and regulatory challenges. This research area has rapidly evolved, with a plethora of innovative nanoengineered materials now being in use, including micelles, nano/microemulsions, liposomes, niosomes, solidlipid nanoparticles, nanostructured lipids and nanostructured carriers. These nanodelivery systems make conventional delivery systems appear archaic and promise better solubilization, protection during processing, improved shelf-life, higher bioavailability as well as controlled and targeted release. This review provides information on the state of knowledge on β-carotene nanodelivery systems adopted for developing functional foods, depicting their classifications, compositions, preparation methods, challenges, release and absorption of β-carotene in the gastrointestinal tract (GIT) and possible risks and future prospects.

Microstructures of encapsulates and their relations with encapsulation efficiency and controlled release of bioactive constituents: A review

Vitamins, peptides, essential oils, and probiotics are examples of health beneficial constituents, which are nevertheless heat-sensitive and possess poor chemical stability. Various encapsulation methods have been applied to protect these constituents against thermal and chemical degradations. Encapsulates prepared by different methods and/or at different conditions exhibit different microstructures, which in turn differently influence the encapsulation efficiency as well as retention of encapsulated core materials. This review provides a summary of various microstructures resulted from the use of selected encapsulation methods or systems, namely, spray coating; co-extrusion; emulsion-, micelle-, and liposome-based; coacervation; and ionic gelation encapsulation, at different conditions. Subsequent effects of the different microstructures on encapsulation efficiency and retention of encapsulated core materials are mentioned and discussed. Encapsulates having compact microstructures resulted from the use of low-surface tension and low-viscosity encapsulants, high-stability encapsulation systems, lower loads of core materials to total solids of encapsulants and appropriate solidification conditions have proved to exhibit higher encapsulation efficiencies and better retention of encapsulated core materials. Encapsulates with hollow, dent, shrunken microstructures or thinner walls resulted from inappropriate solidification conditions and higher loads of core materials, on the other hand, possess lower encapsulation efficiencies and protection capabilities. Encapsulates having crack, blow-hole or porous microstructures resulted from the use of high-viscosity encapsulants and inappropriate solidification conditions exhibit the lowest encapsulation efficiencies and poorest protection capabilities. Compact microstructures and structures formed between ionic biopolymers could be used to regulate the release of encapsulated cores.

Advances in edible nanoemulsions: Digestion, bioavailability, and potential toxicity

The design, fabrication, and application of edible nanoemulsions for the encapsulation and delivery of bioactive agents has been a highly active research field over the past decade or so. In particular, they have been widely used for the encapsulation and delivery of hydrophobic bioactive substances, such as hydrophobic drugs, lipids, vitamins, and phytochemicals. A great deal of progress has been made in creating stable edible nanoemulsions that can increase the stability and efficacy of these bioactive agents. This article highlights some of the most important recent advances within this area, including increasing the water-dispersibility of bioactives, protecting bioactives from chemical degradation during storage, increasing the bioavailability of bioactives after ingestion, and targeting the release of bioactives within the gastrointestinal tract. Moreover, it highlights progress that is being made in creating plant-based edible nanoemulsions. Finally, the potential toxicity of edible nanoemulsions is considered.

Preparation of functional rice cake by using β-carotene-loaded emulsion powder

The purpose of this study was to apply a powdered β-carotene-loaded emulsion to a real food product, Korean traditional rice cakes (Garaedduk). β-Carotene was incorporated into the oil phase of a sodium caseinate-stabilized emulsion. Emulsion powder containing β-carotene was prepared using freeze-drying, and maltodextrin and gum arabic were used as wall materials. Oil/protein/maltodextrin weight ratios of 3:1:2 and 3:1:5 (core-to-wall ratios of 1:1 and 1:2) were used, and gum arabic was added by replacing the amount of maltodextrin for 0.1%, 0.2%, and 0.5% w/w. Manufactured emulsion powders prepared with wall material at a core-to-wall ratio of 1:2 remained stable after reconstitution in terms of particle diameter and ζ-potential. The encapsulation efficiency of the emulsion powder increased by 90% in the presence of maltodextrin at a core-to-wall ratio of 1:2. Garaedduk containing the emulsion powder was then manufactured and it was confirmed that β-carotene was not degraded during the manufacturing process of Garaedduk by using HPLC. The results from this study may be useful for rational designing of functional foods with lipophilic bioactive materials.

Pseudosciaena crocea roe protein-stabilized emulsions for oral delivery systems: In vitro digestion and in situ intestinal perfusion study

Benzyl isothiocyanate (BITC) was encapsulated in oil-in-water emulsions stabilized by Pseudosciaena crocea roe protein isolate (PRPI). The stability, lipid digestion, BITC bioavailability, and retention rate of the emulsions were characterized using a simulated gastrointestinal tract model. Tween-corn and PRPI-medium-chain triglycerides (MCT) emulsions were used as controls. The membrane permeability and BITC absorption from these emulsions were investigated by in situ single-pass intestinal perfusion. The results showed that the PRPI-stabilized emulsions were stable under nonacidic environment conditions. Moreover, the PRPI-corn emulsion had more obvious protective effects than PRPI-MCT and Tween-corn emulsions. Atomic force and confocal laser scanning microscopy images showed that the protein hydrolyzed and oil droplets aggregated during simulated gastric phase digestion. Following the exposure of oil droplets in the small intestine phase, the PRPI-corn emulsion had a high rate of free fatty acid release (99.13 ± 2.49%), and the retention rate and bioavailability of BITC from the PRPI-corn emulsion were 75.93 ± 7.17% and 77.32 ± 5.36%, respectively, which were significantly higher than those measured for the other emulsions (P < 0.05). Moreover, the K_a and P_eff of the PRPI-corn emulsion reached the maximum value at 45 min and then decreased slowly. These results suggest that the PRPI-corn emulsion delivery system is effective in encapsulating, delivering, and protecting BITC. PRACTICAL APPLICATION: This study provides some useful information for the food industry to develop a Pseudosciaena crocea roe protein isolate (PRPI) emulsion that could be successfully used to construct a BITC delivery system and improve benzyl isothiocyanate (BITC) bioavailability. The protective effect on BITC assessed in vitro simulated gastrointestinal tract and in situ single-pass intestinal perfusion are discussed.