Antioxidant capacity of bilberry extract microencapsulated in whey protein hydrogels

Fabrication of blueberry anthocyanins-rich gels based on the apricot polysaccharides with different esterification degrees

To enhance the stability of anthocyanins under conditions such as light, temperature, and pH, an apricot polysaccharide hydrogel for anthocyanins encapsulation was prepared in this study. Apricot polysaccharides with different DEs were prepared by an alkaline de-esterification method. A gel was prepared by mixing the apricot polysaccharides with CaCl2 to encapsulate the anthocyanins; the encapsulation efficiency reached 69.52 ± 0.31 %. Additionally, the gel exhibited favorable hardness (144.17 ± 2.33 g) and chewiness (64.13 ± 1.53 g). Fourier transform infrared (FTIR) and X-ray diffractometer (XRD) spectra confirmed that the formation of the hydrogel primarily relied on electrostatic interactions and hydrogen bonding. Compared with free anthocyanins, it was also found that the gel-encapsulated anthocyanins had a higher retention rate (RR) under different temperatures and light.

Preparation and Physicochemical Analysis of Camellia sinensis cv. 'Ziyan' Anthocyanin Microcapsules

The new tea cultivar Ziyan has a high content of anthocyanin and ester catechins in the raw material, but the conventional processing and application methods are limited. To explore its application potential, the freeze-drying method was used to prepare microcapsules with an embedding time of 30 min, solid content of 30%, and core to wall ratio of 1:10 (g/g). The anthocyanin recovery was 95.94 ± 0.50%, and the encapsulation efficiency was 96.15 ± 0.11%. The stability of microcapsules and composite wall materials was evaluated in the simulation system. Results showed that microcapsules employing a maltodextrin-gum arabic ratio of 2:8 (w/w) as the wall material significantly reduced degradation rates, extending anthocyanin half-life under various storage conditions. Characterization indicated improved physical properties of Ziyan anthocyanin powder post-microencapsulation. FT-IR and DSC- revealed the formation of a new phase between anthocyanins and wall materials, leading to increased enthalpy and enhanced thermal stability. The microencapsulation results of this experiment proved that the storage stability of anthocyanin was effectively enhanced.

Recent Progress in Protein-Polyphenol Assemblies for Biomedical Applications

Nowadays, natural materials as smart building blocks for assembling functional materials have aroused extensive interest in the scientific community. Proteins and polyphenols are typical natural building blocks that are widely used. On the one hand, proteins are one of the most versatile classes of biomolecules, serving as catalysts, signaling molecules, transporters, receptors, scaffolds that maintain the integrity of cell and tissue, and more. On the other hand, the facile adhesion of naturally abundant polyphenols with other substances and their potential biomedical applications have been highly attractive for functional biomaterials fabrication. Additionally, there are a variety of interactions between the proteins and polyphenols, mainly hydrogen bonding, hydrophobic, and ionic interactions. These reversible dynamic interactions enable proteins and polyphenols to form stable protein-polyphenol assemblies and maintain their inherent structures and biological activities in the assemblies. Therefore, protein-polyphenol assemblies can be applied to design a variety of advanced functional materials for biomedical applications. Herein, recent progress in protein-polyphenol particles, capsules, coatings, and hydrogels is summarized, the preparation and application of these assemblies are introduced in detail, and the future of the field is prospected.

Microwave-induced rapid 4D change in color of 3D printed apple/potato starch gel with red cabbage juice-loaded WPI/GA mixture

This study aimed to explore the feasibility of utilizing microparticle mixture (MCPs) comprised of whey protein isolate (WPI), gum Arabic (GA), and freeze-dried red cabbage juice (FDRCJ) as a smart material to realize a rapid color change of 3D printed apple/potato starch gel in response to microwave heating stimulation. The particle size, morphology and thermal stability of WPI/FDRCJ/GA microparticles were examined. Then, the rheology, texture properties and printability of Apple/potato starch gel affected by different concentrations of WPI/FDRCJ/GA microparticles (0, 15, 30, 45, 60% (w/w)) were studied. Results showed that the WPI/FDRCJ/GA microparticles were more thermally stable than pure materials, indicating that the heat-sensitive anthocyanin and other compounds present in FDRCJ were effectively protected by the wall materials (WPI/GA). Moreover, the addition of various microparticle concentrations decreased the samples' mechanical properties but had no significant influence on their loss modulus, viscosity, or printing accuracy. As the microwave heating time increased, the lightness (L*) and yellowness (b*) of microparticle-added samples decreased while the redness (a*) significantly increased (p < 0.05), resulting in a gradual color change from yellow/brown to red. These findings could be useful to produce novel colorful and appealing 4D healthy food products that stimulate consumer appetite.

Immunomodulatory and Antioxidant Effects of Spray-Dried Encapsulated Kale Sprouts after In Vitro Gastrointestinal Digestion

The health-related compounds present in kale are vulnerable to the digestive process or storage conditions. Encapsulation has become an alternative for their protection and takes advantage of their biological activity. In this study, 7-day-old Red Russian kale sprouts grown in the presence of selenium (Se) and sulfur (S) were spray-dried with maltodextrin to assess their capacity to protect kale sprout phytochemicals from degradation during the digestion process. Analyses were conducted on the encapsulation efficiency, particle morphology, and storage stability. Mouse macrophages (Raw 264.7) and human intestinal cells (Caco-2) were used to assess the effect of the intestinal-digested fraction of the encapsulated kale sprout extracts on the cellular antioxidant capacity, the production of nitric oxide (NOx), and the concentrations of different cytokines as indicators of the immunological response. The highest encapsulation efficiency was observed in capsules with a 50:50 proportion of the hydroalcoholic extract of kale and maltodextrin. Gastrointestinal digestion affected compounds' content in encapsulated and non-encapsulated kale sprouts. Spray-dried encapsulation reduced the phytochemicals' degradation during storage, and the kale sprouts germinated with S and Se showed less degradation of lutein (35.6%, 28.2%), glucosinolates (15.4%, 18.9%), and phenolic compounds (20.3%, 25.7%), compared to non-encapsulated ones, respectively. S-encapsulates exerted the highest cellular antioxidant activity (94.2%) and immunomodulatory activity by stimulating IL-10 production (88.9%) and COX-2 (84.1%) and NOx (92.2%) inhibition. Thus, encapsulation is an effective method to improve kale sprout phytochemicals' stability and bioactivity during storage and metabolism.

Purple Wheat: Food Development, Anthocyanin Stability, and Potential Health Benefits

Colored wheats such as black, blue, or purple wheat are receiving a great interest as healthy food ingredients due to their potential health-enhancing attributes. Purple wheat is an anthocyanin-pigmented grain that holds huge potential in food applications since wheat is the preferred source of energy and protein in human diet. Purple wheat is currently processed into a variety of foods with potent antioxidant properties, which have been demonstrated by in vitro studies. However, the health impacts of purple wheat foods in humans still require further investigations. Meanwhile, anthocyanins are vulnerable molecules that require special stabilization treatments during food preparation and processing. A number of stabilization methods such as co-pigmentation, self-association, encapsulation, metal binding, and adjusting processing conditions have been suggested as a means to diminish the loss of anthocyanins in processed foods and dietary supplements. The present review was intended to provide insights about purple wheat food product development and its roles in human health. In addition, methods for stabilizing anthocyanins during processing were briefly discussed.

Recent progress in emulsion gels: from fundamentals to applications

Emulsion gels, also known as gelled emulsions or emulgels, have garnered great attention both in fundamental research and practical applications due to their superior stability, tunable morphology and microstructure, and promising mechanical and functional properties. From an application perspective, attention in this area has been, historically, mainly focused on food industries, e.g., engineering emulsion gels as fat substitutes or delivery systems for bioactive food ingredients. However, a growing body of studies has, in recent years, begun to demonstrate the full potential of emulsion gels as soft templates for designing advanced functional materials widely applied in a variety of fields, spanning chemical engineering, pharmaceutics, and materials science. Herein, a concise and comprehensive overview of emulsion gels is presented, from fundamentals to applications, highlighting significant recent progress and open questions, to scout for and deepen their potential applications in more fields.

Effects of encapsulation methods on bioaccessibility of anthocyanins: a systematic review and meta-analysis

Anthocyanins have multiple health benefits. However, they are prone to degradation during gastrointestinal digestion, impeding their utilization. Various encapsulation systems have been proposed to improve their bioaccessibility and bioavailability. This review aims to provide a systematic evaluation and meta-analysis of published studies examining the effect of microencapsulation on the bioaccessibility of anthocyanins. A comprehensive and systematic literature search of three databases (Scopus, PubMed, and Web of Science) was conducted. Studies were selected according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria and were reviewed independently by two investigators. Overall, 34 articles were included in the systematic review and 24 were included in the meta-analysis. The fold changes in bioaccessibility between encapsulated and non-encapsulated anthocyanins from eligible studies were calculated. The median and 95% confidence intervals (CI) of the fold changes for spray-drying (median 1.23, 95% CI 0.91-1.92), freeze-drying (median 1.19, 95% CI 0.61-1.28), simple coacervation (median 1.80, 95% CI 1.41-3.20), and complex coacervation (median 1.61, 95% CI 0.21-25.00) were calculated. Simple coacervation showed a promising protection against degradation during in vitro digestion. However, when a large number of anthocyanins cannot be released from the microparticles during digestion, encapsulation impedes the bioaccessibility of anthocyanins.

Phenolic-protein interactions: insight from in-silico analyses – a review

Phenolic compounds are ubiquitous plant secondary metabolites that possess various biological activities and are known to interact with proteins, altering their structure and properties. Therefore, interactions between these compounds and proteins has gained increasing attention due to their potential benefits to human health and for exploitation by the food industry. Phenolic compounds and proteins can form complexes via covalent linkages and/or non-covalent interactions through hydrophobic, electrostatic, van der Waals forces and hydrogen bonding. This review describes possible mechanisms of phenol-protein complex formation, their physiological action and activities that are important in the food industry, and possible outcomes in the terms of molecular docking and simulation analysis. The conformational changes of the protein upon binding with polyphenols can lead to the folding or unfolding of the protein molecules, forming insoluble or soluble complexes. The concentration of polyphenols, their molecular weight and structure, ions/cofactors and conditions of the system determine the precipitation or solubilization of the complex, affecting their nutritional and functional properties as well as their bioactivities. In this regard, molecular docking and simulation studies of phenolic-protein interactions allows comprehensive virtual screening of competitive/non-competitive and site-specific/non-specific conjugation of phenolics with different protein targets and facilitates understanding the observed effects. The docking analysis of flavonoids with enzymes and milk proteins has indicated their potential application in producing nutraceuticals and functional foods. Thus, combining molecular docking and simulation studies with experimental techniques is vital for better understanding the reactions that take place during digestion to engineer and manufacture novel food ingredients with desirable pharmacological properties and as potential food additives.

Graphical Abstract

Colorimetric Indicators Based on Anthocyanin Polymer Composites: A Review

This review explores the colorimetric indicators based on anthocyanin polymer composites fabricated in the last decade, in order to provide a comprehensive overview of their morphological and compositional characteristics and their efficacy in their various application fields. Notably, the structural properties of the developed materials and the effect on their performance will be thoroughly and critically discussed in order to highlight their important role. Finally, yet importantly, the current challenges and the future perspectives of the use of anthocyanins as components of colorimetric indicator platforms will be highlighted, in order to stimulate the exploration of new anthocyanin sources and the in-depth investigation of all the possibilities that they can offer. This can pave the way for the development of high-end materials and the expansion of their use to new application fields.

Effects of casein on the stability, antioxidant activity, and bioavailability of lotus anthocyanins

Effects of casein on the stability, antioxidant activity, and bioavailability of lotus anthocyanins were investigated. Casein could inhibit the unsatisfactory pH-induced color change of lotus anthocyanins, and improved their photo, oxidation, and thermal stabilities. During the simulated digestion, the anthocyanin retention increased from 65.39 to 76.14 mg C3G/L with the protection of casein, while the DPPH and ABTS scavenging activities of lotus anthocyanins with casein increased to 62.33% and 46.58%, respectively. However, casein with lower concentration showed a better protective effect on lotus anthocyanins due to its self-aggregation tendency at high dose. The zebrafish model further verified that casein could enhance the bioavailability of lotus anthocyanins. Furthermore, molecular docking revealed that casein could interact with anthocyanin by hydrogen bond and hydrophobic interaction, which led to the stronger stability and bioavailability of lotus anthocyanins. The results conveyed that casein could be used as a wall material to protect anthocyanins. PRACTICAL APPLICATIONS: Anthocyanins are natural colorants with multiple biological activities, but the poor stability during processing and digestion limits their application in food industry. In the present research, casein exhibited conspicuous ability to enhance the stability of lotus anthocyanins toward detrimental conditions. Additionally, casein could preserve anthocyanins from degradation during digestion and thus improve the bioavailability. These findings indicated that casein could serve as a potential carrier for encapsulating and delivering anthocyanins. The better stability and bioavailability would promote the application of anthocyanins in food products and human health.

Application of Nanomaterials to Ensure Quality and Nutritional Safety of Food

Nanomaterials (NMs) are emerging novel tools for preserving quality, enhancing shelf life, and ensuring food safety. Owing to the distinctive physicochemical characters, engineered NMs under varying sizes and dimensions have great potentials for application in the manufacturing, packaging, processing, and safety of quality agrifood. The promise of various kinds of novel NMs that are useful for food industries has opened a possibility of a new revolution in agroprocessing industries in both the emerging and advanced nations. The rapid advancement of nanoscience has provided a great impact on material science that has allowed researchers to understand every aspect of molecular complexity and its functions in life sciences. The reduced size of NMs that increase the surface area is useful in the specific target of different organs, and biodegradable nanospheres are helpful in the transport of bioactive molecules across the cellular barriers. However, nanotechnology creates a great revolution in several sections including agriculture and food industry and also reduces environmental pollution, while the toxicity of some NMs in the food industry poses a great concern to researchers for their greater application. However, most of the developed countries have regulatory control acts but developing countries do not have them yet. Therefore, for the safe use of NMs and also to minimize the health and environmental risks in both the developed and developing countries, it is indispensable to recognize the toxicity-constructed, toxicodynamic, and toxicokinetic features of NMs, which should carefully be emphasized at the home and industrial levels. The current study highlights the updates of the NMs to safeguard the quality and nutritional safety of foods at home and also at the industrial level.

Utilization of diverse protein sources for the development of protein-based nanostructures as bioactive carrier systems: A review of recent research findings (2010-2021)

Consumer awareness of the relationship between health and nutrition has caused a substantial increase in the demand for nutraceuticals and functional foods containing bioactive compounds (BACs) with potential health benefits. However, the direct incorporation of many BACs into commercial food and beverage products is challenging because of their poor matrix compatibility, chemical instability, low bioavailability, or adverse impact on food quality. Advanced encapsulation technologies are therefore being employed to overcome these problems. In this article, we focus on the utilization of plant and animal derived proteins to fabricate micro and nano-particles that can be used for the oral delivery of BACs such as omega-3 oils, vitamins and nutraceuticals. This review comprehensively discusses different methods being implemented for fabrications of protein-based delivery vehicles, types of proteins used, and their compatibility for the purpose. Finally, some of the challenges and limitations of different protein matrices for encapsulation of BACs are deliberated upon. Various approaches have been developed for the fabrication of protein-based microparticles and nanoparticles, including injection-gelation, controlled denaturation, and antisolvent precipitation methods. These methods can be used to construct particle-based delivery systems with different compositions, sizes, surface hydrophobicity, and electrical characteristics, thereby enabling them to be used in a wide range of applications.

Optimization and Encapsulation of Phenolic Compounds Extracted from Maize Waste by Freeze-Drying, Spray-Drying, and Microwave-Drying Using Maltodextrin

Cornsilk is maize waste containing phenolic compounds. In this study, freeze-drying, spray-drying, and microwave-drying techniques were evaluated for the encapsulation of cornsilk's phenolic compounds using maltodextrin as wall material. The results of antioxidant properties showed that freeze-drying was more efficient than microwave-drying and spray-drying techniques. The highest recovery of phenolic compounds was obtained with freeze-drying. The microstructure, DSC, and FTIR data showed that the encapsulation process was effective, and freeze-drying was the best drying technique. The physical properties of the microparticles greatly changed with the drying techniques. This study revealed that the phenolic compounds of the cornsilk extract can be successfully encapsulated and valorized.

Combination of copigmentation and encapsulation strategies for the synergistic stabilization of anthocyanins

Copigmentation and encapsulation are the two most commonly used techniques for anthocyanin stabilization. However, each of these techniques by itself suffers from many challenges associated with the simultaneous achievement of color intensification and high stability of anthocyanins. Integrating copigmentation and encapsulation may overcome the limitation of usage of a single technique. This review summarizes the most recent studies and their challenges aiming at combining copigmentation and encapsulation techniques. The effective approaches for encapsulating copigmented anthocyanins are described, including spray/freeze-drying, emulsification, gelation, polyelectrolyte complexation, and their combinations. Other emerging approaches, such as layer-by-layer deposition and ultrasonication, are also reviewed. The physicochemical principles underlying the combined strategies for the fabrication of various delivery systems are discussed. Particular emphasis is directed toward the synergistic effects of copigmentation and encapsulation, for example, modulating roles of copigments in the processes of gelation and complexation. Finally, some of the major challenges and opportunities for future studies are highlighted. The trend of integrating copigmentation and encapsulation has been just started to develop. The information in this review should facilitate the exploration of the combination of multistrategy and the fabrication of robust delivery systems for copigmented anthocyanins.

Hydrogels: Characteristics and Application as Delivery Systems of Phenolic and Aroma Compounds

Complex challenges are facing the food industry as it develops novel and innovative products for the consumer marketplace. Food processing and preservation are primarily based on achievement and maintenance of safety in order to protect consumers, as well as extending product shelf life under the relevant conditions of storage, transport and distribution. Maximizing retention of bioactives with recognized positive effects on health typically comes under consideration when the previous two priorities have been achieved. This review introduces the potential applications of hydrogels as delivery systems of high-value bioactives like phenolics and aromas. If they are successfully encapsulated within the gel structures, their release can be controlled, which opens a wide range of applications, not only in food, but also in the pharmaceutical and cosmetic industries. Hydrogels are three-dimensional network structures which can absorb significant amounts of water. They have the ability to thicken the system and therefore can be used to design products with desired properties. In order to preserve the valuable components, it is necessary to know their physicochemical properties, in addition to the properties of the polymer used for hydrogel preparation.

Recent advances in the structure, synthesis, and applications of natural polymeric hydrogels

Hydrogels, polymeric network materials, are capable of swelling and holding the bulk of water in their three-dimensional structures upon swelling. In recent years, hydrogels have witnessed increased attention in food and biomedical applications. In this paper, the available literature related to the design concepts, types, functionalities, and applications of hydrogels with special emphasis on food applications was reviewed. Hydrogels from natural polymers are preferred over synthetic hydrogels. They are predominantly used in diverse food applications for example in encapsulation, drug delivery, packaging, and more recently for the fabrication of structured foods. Natural polymeric hydrogels offer immense benefits due to their extraordinary biocompatible nature. Hydrogels based on natural/edible polymers, for example, those from polysaccharides and proteins, can serve as prospective alternatives to synthetic polymer-based hydrogels. The utilization of hydrogels has so far been limited, despite their prospects to address various issues in the food industries. More research is needed to develop biomimetic hydrogels, which can imitate the biological characteristics in addition to the physicochemical properties of natural materials for different food applications.

Effect of whey protein isolate on the stability and antioxidant capacity of blueberry anthocyanins: A mechanistic and in vitro simulation study

The processing stability and antioxidant capacity of blueberry anthocyanins (ANs) in the presence of whey protein isolate (WPI) were examined. WPI was found to enhance both the stability and antioxidant activity of ANs during processing and simulated in vitro digestion, especially at a concentration of 0.15 mg·mL^-1. Fluorescence and ultraviolet-visible absorption spectroscopy showed that ANs were primarily stabilized by hydrophobic forces between WPI and malvidin-3-O-galactoside (M3G), the major anthocyanin monomer. Circular dichroism and Fourier-transform infrared spectroscopy confirmed that the structure of WPI changed and the microenvironments of certain amino acid residues were modulated by non-covalent binding to M3G; furthermore, fewer α-helices and more β-sheets were formed. Molecular docking studies revealed that WPI, especially immunoglobulin (IgG), contributed the most to ANs stability via hydrogen bonds and hydrophobic forces according to molecular docking scores (-141.30 kcal/mol). These results provided an important fundamental basis for improving the stabilities of ANs in milk systems.

Effects of α-casein and β-casein on the stability, antioxidant activity and bioaccessibility of blueberry anthocyanins with an in vitro simulated digestion

Blueberry anthocyanins are well-known for their diverse biological functions. However, the instability during digestion results in their weak bioavailability. The current study aimed to investigate the alteration in the stability, antioxidant capacity and bioaccessibility of blueberry anthocyanins with the addition of α-casein and β-casein in a simulated digestion system using pH differential method, HPLC-MS analysis, peroxyl scavenging capacity (PSC) assay, cellular antioxidant activity (CAA) and penetration test. The results showed that both α-casein and β-casein could increase the stability of blueberry anthocyanins during intestinal digestion and protect their antioxidant capacity. Moreover, the addition of α-casein or β-casein would enhance the bioaccessibility of blueberry anthocyanins. In conclusion, our study highlights that the interaction between α-casein or β-casein with blueberry anthocyanins can protect the compounds against influences associated with the simulated digestion.

Emblicanin rich Emblica officinalis extract encapsulated double emulsion: controlled release of bioactive during phagocytosis and in vitro digestion

ABSTRACT

Controlled release of Emblicanin rich water soluble extract of Emblica officinalis (EEO) from the inner phase of water-in-oil-in-water type double emulsion (DE), during in vitro digestion and phagocytosis was investigated. It was observed that release of EEO (measured as total polyphenols and gallic acid by HPLC) from inner phase of DE was maximum during intestinal digestion followed by gastric and salivary digestion. Main reason was increased particle size of emulsion droplets and change in zeta potential by the action of digestive enzymes. ACE inhibitory activity and antioxidant activity [determined by ABTS (99.58 ± 7.24 mM/mL), DPPH (76.93 ± 0.93 µM/mL) and FRAP (6.34 ± 0.13 mM/mL)] was observed on the higher side in the intestinal digesta of EEO-encapsulated DE (EEODE) as compared to salivary and gastric digesta. However, reverse trend was observed in control sample (unencapsulated-EEO). Phagocytic activity of EEODE increased with increasing its concentration of 2-10 µL. These results indicated that the developed DE matrix was effective in protecting active components of EEO during harsh digestive conditions as evident by sustained/target release. This newly developed EEODE formulation can be used as functional ingredient in the preparation of different dairy and food based functional products.

GRAPHIC ABSTRACT

Natural biopolymer-based hydrogels for use in food and agriculture

Hydrogels are important materials that are of high scientific interest and with numerous applications. Natural polymer-based hydrogels are preferred to synthetic ones due to their safety, biocompatibility, and ecofriendly properties. They have been studied extensively and implemented in various fields, such as medicine, cosmetics, personal-care products, water purification, and more. This review focuses on the applications of nature-sourced polymer-based hydrogels in food and agriculture. Different types of biopolymers and crosslinking agents, and various methods for hydrogel formation are described. The physicomechanical properties and applied activities of the resulting materials are also comprehensively discussed. Biodegradable synthetic polymers are outside the scope of this review. © 2020 Society of Chemical Industry.

Designing multiple bioactives loaded emulsions for the formulations for diets of elderly

In this study, a stable double emulsion loaded with essential bioactives for the elderly was prepared using a two-step mechanical emulsification process.

Chokeberry polyphenols preservation using spray drying: effect of encapsulation using maltodextrin and skimmed milk on their recovery following in vitro digestion

Aim: Microencapsulation of chokeberry extracts was performed in order to improve functionality, stability, and bioavailability of extracted polyphenols.Methods: Chokeberry fruits and juice by-product (waste) extracts were spray-dried by using two carriers, maltodextrin and skimmed milk. Morphological and physicochemical characteristics of the obtained powders were analysed. In vitro simulated digestion model was used as an indicator of polyphenolics bioavailability.Results: The moisture content varied between 3.39 and 4.61%, zeta potential had negative values (35-39 mV), maltodetrin powders were smaller (4.27-5.12 µm) compared to skimmed ones (8.50-11.01 µm). All microparticles exhibited high encapsulation efficiency of total polyphenols and anthocyanins (73-97% and 63-96%, respectively). For both extract types, maltodextrin powders released higher phenolics content compared to skimmed milk. During in vitro digestion, maltodextrin exhibited a higher protective effect on both active compounds.Conclusion: Taking into account the obtained results, chokeberry polyphenols stability might be improved using spray drying technique, and maltodextrin showed better properties.

Design of microcapsules with bilberry seed oil, cold-set whey protein hydrogels and anthocyanins: Effect of pH and formulation on structure formation kinetics and resulting microstructure during purification processing and storage

Encapsulation of polar and non-polar bioactive compounds from bilberries was achieved by designing microcapsules with bilberry seed oil (BSO) distributed in an aqueous phase of anthocyanins (AC) stabilized by whey protein isolate (WPI). Non-thermal emulsification method (o/w/o) was developed and the effect of pH (3 or 4.5), concentration of WPI (8.4-10.8% w/w), addition of AC (72-216 ppm) and emulsifier on the structure-forming kinetics, resulting microstructure during storage and after centrifugation and washing was investigated. Agglomeration of BSO was observed in all microcapsules at pH 4.5 due to slow gelling process and in samples at pH 3 at low concentrations of WPI (≤8.4%). Capsules with pH 3 (9.6-10.8% WPI) had weak structures but as the gelling process was faster, it generated an even distribution of BSO droplets. All samples at pH 4.5 and samples with WPI concentration ≥10.8% at pH 3 exhibited intact structures after centrifugation and washing.

Effect of In Vitro Digestion on Water-in-Oil-in-Water Emulsions Containing Anthocyanins from Grape Skin Powder

The effects of in vitro batch digestion on water-in-oil-in-water (W/O/W) double emulsions encapsulated with anthocyanins (ACNs) from grape skin were investigated. The double emulsions exhibited the monomodal distribution (d = 686 ± 25 nm) showing relatively high encapsulation efficiency (87.74 ± 3.12%). After in vitro mouth digestion, the droplet size (d = 771 ± 26 nm) was significantly increased (p < 0.05). The double W₁/O/W₂ emulsions became a single W₁/O emulsion due to proteolysis, which were coalesced together to form big particles with significant increases (p < 0.01) of average droplet sizes (d > 5 µm) after gastric digestion. During intestinal digestion, W₁/O droplets were broken to give empty oil droplets and released ACNs in inner water phase, and the average droplet sizes (d < 260 nm) decreased significantly (p < 0.05). Our results indicated that ACNs were effectively protected by W/O/W double emulsions against in vitro mouth digestion and gastric, and were delivered in the simulated small intestine phase.

Physico-Chemical Changes of Composite Whey Protein Hydrogels in Simulated Gastric Fluid Conditions

Polysaccharide blended whey protein isolate (WPI) hydrogels were developed for the delivery of black carrot ( Daucus carota) concentrate as bioactive agent in simulated gastric fluid (SGF). Pectin (PC), gum tragacanth (GT), and xanthan gum (XG) were blended as additional polymers to modulate the release characteristics of the WPI hydrogels. Experiments showed that sole whey protein (C), XG, and GT blended hydrogels possessed restricted release profiles 67%, 61%, and 67%, respectively, whereas PC samples attained higher release rates (83%) ( p < 0.05). Interactions between polymers and aqueous medium were analyzed by nuclear magnetic resonance relaxometry. C (82 ms) and GT (84 ms) hydrogels attained higher T₂ values than PC (74 ms) and XG (73 ms) samples in SGF. Hardness of only XG hydrogels increased from 1.9 to 4.1 N after gastric treatment. Physicochemical changes within hydrogels during release were also investigated, and hydrogels were proved to be appropriate for desired delivery purposes.

Protein-Based Delivery Systems for the Nanoencapsulation of Food Ingredients

Many proteins possess functional attributes that make them suitable for the encapsulation of bioactive agents, such as nutraceuticals and pharmaceuticals. This article reviews the state of the art of protein-based nanoencapsulation approaches. The physicochemical principles underlying the major techniques for the fabrication of nanoparticles, nanogels, and nanofibers from animal, botanical, and recombinant proteins are described. Protein modification approaches that can be used to extend their functionality in these nanocarrier systems are also described, including chemical, physical, and enzymatic treatments. The encapsulation, retention, protection, and release of bioactive agents in different protein-based nanocarriers are discussed. Finally, some of the major challenges in the design and fabrication of protein-based delivery systems are highlighted.

Influence of process conditions on the physicochemical properties of jussara pulp (Euterpe edulis) powder produced by spray drying

Abstract The objective of this work was to optimize the spray drying of jussara pulp using mixtures of modified starch (MS) with whey protein concentrate (WPC) or soy protein isolate (SPI) as the carrier agents. Two central composite rotatable designs were used to evaluate the effect of the independent variables of inlet air temperature (140 °C to 200 °C), carrier agent concentration - CAC (0.5 to 2 g carrier agent/g jussara pulp solids) and the proportions of MS:WPC or MS:SPI (5 to 30 g WPC or SPI/100 g carrier agent) on the following responses for powders formulated with MS:WPC and MS:SPI, respectively: moisture content (0.3% to 1.4% and 0.6% to 1.2%), solubility (78.0% to 92.9% and 78.9% to 83.8%), retention of total anthocyanins (49.2% to 82.9% and 34.1% to 96.9%), encapsulation efficiency (98.5% to 99.7% and 98.5% to 99.5%), hue angle (9.1 to 44.0 and 3.7 to 42.6), chroma (10.0 to 15.3 and 9.2 to 14.3) and process yield (33.2% to 55.5% and 49.9% to 78.5%). The inlet air temperature 170 °C, CAC of 1.25 and 2 g/g jussara pulp solids and proportion of MS:WPC or MS:SPI of 17.5 and 30 g/100 g were recommended as the selected conditions.

Micro- and nano bio-based delivery systems for food applications: In vitro behavior

Micro- and nanoencapsulation is an emerging technology in the food field that potentially allows the improvement of food quality and human health. Bio-based delivery systems of bioactive compounds have a wide variety of morphologies that influence their stability and functional performance. The incorporation of bioactive compounds in food products using micro- and nano-delivery systems may offer extra health benefits, beyond basic nutrition, once their encapsulation may provide protection against undesired environmental conditions (e.g., heat, light and oxygen) along the food chain (including processing and storage), thus improving their bioavailability, while enabling their controlled release and target delivery. This review provides an overview of the bio-based materials currently used for encapsulation of bioactive compounds intended for food applications, as well as the main production techniques employed in the development of micro- and nanosystems. The behavior of such systems and of bioactive compounds entrapped into, throughout in vitro gastrointestinal systems, is also tracked in a critical manner. Comparisons between various in vitro digestion systems (including the main advantages and disadvantages) currently in use, as well as correlations between the behavior of micro- and nanosystems studied through in vitro and in vivo systems were highlighted and discussed here for the first time. Finally, examples of bioactive micro- and nanosystems added to food simulants or to real food matrices are provided, together with a revision of the main challenges for their safe commercialization, the regulatory issues involved and the main legislation aspects.

Formation of whey protein-polyphenol meso-structures as a natural means of creating functional particles

Whey proteins provide structure and nutritional properties in food, while berry juices are thought to have biological activity that can impart anti-inflammatory health effects. In combination, the two could be an excellent source of necessary and supplemental nutrients as well as expand the functionality of whey proteins in food structures. The objectives of this investigation were to (1) develop an approach for particle formation between whey protein and cranberry, blackcurrant, or muscadine grape juices, (2) determine resulting particle composition and physical characteristics, and (3) evaluate properties related to food structure stability and maintenance of phytochemical bioactivity. Particles were formed by combining 20% w/w whey protein with juice containing 50, 250, or 500 μg g(-1) total phenolics, adjusting pH to 4.5, and centrifuging to collect aggregated particles. Particles had an approximate molar ratio of 9-50 proteins per polyphenol, and the ratio increased with increasing phenolic content of the juice used to create the particles. Particle size ranged from 1-100 μm at pH 4.5, compared to 10 μm particles that formed when whey protein isolate alone was precipitated at pH 4.5. Polyphenols and other juice components, such as acids and sugars appeared to be involved in particle formation. Particles improved foam stability, and the anti-inflammatory properties of entrapped polyphenols were maintained in the particles. Highly functional protein-polyphenol particles can be designed to stabilize food structures and simultaneously deliver polyphenols associated with health benefits.

Loading of anthocyanins on chitosan nanoparticles influences anthocyanin degradation in gastrointestinal fluids and stability in a beverage

The optimal preparation parameters to create anthocyanin-loaded chitosan nanoparticles was predicted using response surface methodology (RSM). A Box-Behnken design was used to determine the preparation parameters that would achieve the preferred particle size and high encapsulation efficiency. The result suggested that the optimized conditions were 2.86mg/mL carboxymethyl chitosan (CMC), 0.98mg/mL chitosan hydrochloride (CHC) and 5.97mg anthocyanins. Using the predicted amounts, the experimentally prepared particles averaged 219.53nm with 63.15% encapsulation efficiency. The result was less than 5% different than the predicted result of 214.83nm particle size and 61.80% encapsulation efficiency. Compared with the free anthocyanin solution, the anthocyanin-loaded chitosan nanoparticles showed a slowed degradation in simulated gastrointestinal fluid. Compared with the free anthocyanin solutions in a model beverage system, the stability of the anthocyanins was increased in the anthocyanin-loaded chitosan nanoparticles.