Stability and structural properties of bee pollen protein hydrolysate microencapsulated using maltodextrin and whey protein concentrate

Fabrication of biopolymer stabilized microcapsules for enhancing physicochemical stability, antioxidant and antimicrobial properties of cinnamon essential oil

The current study entails the encapsulation validity to enclose naturally occurring food preservatives, such as cinnamon essential oil (CM), within various wall materials. This approach has demonstrated enhanced encapsulated compounds' stability, efficiency, and bioactivity. The base carrier system consisted of a solid lipid (Berry wax, RW) individually blended with whey protein (WYN), maltodextrin (MDN), and gum Arabic (GMC) as wall materials. The resulting formulations were freeze-dried: WYN/RW/CM, MDN/RW/CM, and GMC/RW/CM. The study comprehensively analyzed encapsulation efficiency, morphology, crystallinity, thermal, and physiochemical properties. When RW was combined with WYN, MDN, and GMC, the microcapsule WYN/RW/CM showed the highest efficiency at 93.4 %, while the GMC/RW/CM exhibited the highest relative crystallinity at 46.54 %. Furthermore, the investigation assessed storage stability, release of bioactive compounds, and oxidative stability during storage at 4 °C/ 25 % RH ± 5 % and 25 °C/40 % RH ± 5 % for 55 days, revealing optimal stability in the WYN/RW/CM microcapsule. Additionally, the antimicrobial activity was assessed at various concentrations of microcapsules, revealing their inhibitory effect against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) bacteria. The WYN/RW/CM microcapsule exhibited the highest inhibition activity in both strains, reaching 40 mm. This study demonstrates that combining WYN with RW as a wall material has greater efficiency in encapsulation and potential uses in various industrial sectors.

New perspective on protein-based microcapsules as delivery vehicles for sensitive substances: A review

Sensitive substances have attracted wide attention due to their rich functional activities, such as antibiosis activities, antioxidant activities and prevent disease, etc. However, the low stability of sensitive substances limits their bioavailability and functional activities. Protein-based microcapsules can encapsulate sensitive substances to improve their adverse properties due to their good stability, strong emulsifying ability and wide source. Therefore, it is necessary to fully elaborate and summarize protein-based microcapsules to maximize their potential benefits in nutritional interventions. The focus of this review is to highlight the classification of protein-based microcapsules. In addition, the principles, advantages and disadvantages of preparation methods for protein-based microcapsules are summarized. Some novel preparation methods for protein-based microcapsules are also emphasized. Moreover, the mechanism of protein-based microcapsules that release sensitive substances in vitro is elucidated and summarized. Furthermore, the applications of protein-based microcapsules are outlined. Protein-based microcapsules can effectively encapsulate sensitive substances, which improve their bioavailability, and provide protective effects during storage and gastrointestinal digestion. In addition, microcapsules can improve the sensory quality of food and enhance its stability. The performance of protein-based microcapsules for delivering sensitive substances is influenced by factors such as protein type, the ratio between protein ratio and the other wall material, the preparation process, etc. Future research should focus on the new composite protein-based microcapsule delivery system, which can be applied to in vivo research and have synergistic effects and precise nutritional functions. In summary, protein-based microcapsules have broader research prospects in the functional foods and nutrition field.

Multi-layer encapsulation of pumpkin (Cucurbita maxima L.) seed protein hydrolysate and investigating its release and antioxidant activity in simulated gastrointestinal digestion

Because of their high protein content, easy access and low cost, pumpkin seeds are a valuable raw material for the preparation of antioxidant protein hydrolysates. Micro-coating is an effective method to protect bioactive compounds against destruction. In order to strengthen the alginate hydrogel network loaded with pumpkin seed protein hydrolysate (PSPH), CMC was added as part of its formulation in the first step, and chitosan coating was used in the second step. Then, swelling amount, release in the simulated gastrointestinal environment (SGI), antioxidant activity after SGI, Fourier transform infrared spectroscopy (FTIR), zeta potential, dynamic light scattering (DLS), polydispersity index (PDI) and scanning electron microscopy (SEM) of the samples were evaluated. The results showed that, the swelling amount of the chitosan-alginate hydrogel was lower than the chitosan-alginate-CMC sample, and with the increase in chitosan concentration, the swelling amount decreased. The release amount in the chitosan-alginate sample was higher than that in the chitosan-alginate-CMC sample, and with the increase in chitosan concentration, the release rate decreased. Also, the amount of release increased with the passage of time. The highest antioxidant activity belonged to the chitosan-alginate sample in SGI, and it increased with increasing the chitosan concentration. All findings demonstrated that the use of multi-component hybrid systems is a useful method for the protection of bioactive compounds against destruction, their antioxidant activities and their release behavior.

Composite alginate-based hydrogel delivery of antioxidant pumpkin protein hydrolysate in simulated gastrointestinal condition

Pumpkin seeds are rich in protein (24-36.5%). Some of them are consumed as nuts, while others are regarded as waste and used for feeding animals. Protein hydrolysates from pumpkin seeds possess some bioactive properties, such as anti-oxidant activity. In this work, various composite alginate hydrogels contain Aloe vera, CMC, and tragacanth have been employed to protect PSPH against degradation in simulated gastrointestinal digestion (SGI) and regulate its release rate. The encapsulation efficiency of PSPH in plain alginate and beads with Aloe vera, CMC, and tragacanth combinations was 71.63, 75.63, 85.07, and 80.4%, respectively. The release rate of the plain alginate beads was %30.23 in the SGF and %52.26 in the SIF, and decreased in the composite-based beads. The highest decreasing rate in the antioxidant activity during SGI was observed in free PSPH, and the decreasing rate slowed down in the alginate-based composites. The swelling rate in plain alginate was %-23.43 and %25.43 in the SGF and SIF, respectively, and increased in the composite-based beads. The FTIR spectra of hydrogels before and after loading with PSPH showed identical absorption patterns and were similar to each other. Based on the data for SEM, it was revealed that substituting other polymers in polymer combinations with alginates resulted in a porosity reduction of the beads and smoother and more uniform surfaces. Based on the results, the combination of polysacchared with alginate could protect and increase the applicability of PSPH as a functional component in the food industry.

Advances in protein-based microcapsules and their applications: A review

Due to their excellent emulsification, biocompatibility, and biological activity, proteins are widely used as microcapsule wall materials for encapsulating drugs, natural bioactive substances, essential oils, probiotics, etc. In this review, we summarize the protein-based microcapsules, discussing the types of proteins utilized in microcapsule wall materials, the preparation process, and the main factors that influence their properties. Additionally, we conclude with examples of the vital role of protein-based microcapsules in advancing the food industry from primary processing to deep processing and their potential applications in the biomedical, chemical, and textile industries. However, the low stability and controllability of protein wall materials lead to degraded performance and quality of microcapsules. Protein complexes with polysaccharides or modifications to proteins are often used to improve the thermal instability, pH sensitivity, encapsulation efficiency and antioxidant capacity of microcapsules. In addition, factors such as wall material composition, wall material ratio, the ratio of core to wall material, pH, and preparation method all play critical roles in the preparation and performance of microcapsules. The application area and scope of protein-based microcapsules can be further expanded by optimizing the preparation process and studying the microcapsule release mechanism and control strategy.

Effect of ultrasound and thermal pretreatments on antioxidant activity of egg white hydrolysate

The use of ultrasonic (US) treatment of egg white prior to enzymatic hydrolysis to produce hydrolysate with antioxidant activity was investigated. The state of egg white (raw vs. cooked form) along with two levels of Alcalase (1% and 10% (w/w) protein) was applied. Hydrolysis and antioxidant activity of hydrolysate increased by US pretreatment at intensity of 41.53 W/cm2 . The hydrolysate prepared from US treatment on raw egg white hydrolyzed by 1% Alcalase (US-R1%) showed the lowest degree of hydrolysis (DH); however, its 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging and ferric reducing antioxidant power activities were the highest. In contrast, the highest cytoprotective effect and intracellular reactive oxygen species scavenging activity were more notable in the hydrolysate prepared from US treatment of boiled egg white hydrolyzed by 10% Alcalase (US-B10%), which also exhibited the highest DH and metal chelation ability. The hydrolysate possessing cellular antioxidant activity (CAA) showed the highest proportion of small molecular weight peptides (<200 Da). Fourier-transform infrared spectroscopy revealed an increase of N- and C-terminal ends at 1500 and 1400 cm-1 , respectively, in concomitant with a decrease of amide I. Principal component analysis showed clear differentiation of spectra from different levels of enzyme according to their DH, C-terminal ends, and antioxidant activity. Our findings suggested that cooked egg white followed by US pretreatment was beneficial to produce hydrolysate containing high CAA.

Structure-property relationships of epoxy functionalized enoate ester-based tailored hybrid gels doped with different polysaccharides

Natural polymer-based cryogenically structured hybrid gels as support matrices were prepared by constructing synergistic multiple interactions among copolymer poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) and different polysaccharides; hyaluronic acid (HyA), dextrin (Dex), maltodextrin (MDex), carboxymethyl cellulose (CMC) and xanthan gum (XG). Great improvement in thermal stability was achieved in the presence of CMC and MDex. In the as-prepared state, the highest modulus is observed in HyA-doped hydrogels, while in the swollen-state, CMC-doped hydrogels have a greater modulus. Hybrid cryogels showed higher swelling than hybrid hydrogels in all cases, while maximum swelling was obtained in HyA-doped hybrid cryogels. Solvent selection methodology based on solvent/polymer interaction was presented using 16 solvents with various solubility parameters. The PHG/XG network exhibited a more gradual swelling, whereas water uptake of hybrids doped with Dex and MDex were more pronounced dependent on temperature. The adsorption capacity of hybrid cryogels for methyl orange (MO) is both higher and faster compared to hydrogels, while a decrease in the adsorption capacity of hybrid cryogels at equilibrium was observed in the order of MDex > Dex > XG > CMC > HyA. This study provides a perspective on cryogenically structured hybrid material design by comparatively presenting the effectiveness of different polysaccharides that can be used for MO adsorption in water purification assemblies.

The enzymatic modification of whey-proteins for spray drying encapsulation of Ginkgo-biloba extract

Ginkgo biloba extract (GBLE) contains many bioactives including flavonoids and terpene trilactones that play some pharmacological roles. These compounds are sensitive to operating conditions; so, encapsulation is a suitable approach to protect them. In this study, different carriers including maltodextrin (MD), and its combination with gum-Arabic (MD-GA), whey protein concentrate (MD-WPC), and whey-protein hydrolysate (MD-HWPC) were used to encapsulate GBLE. Powder production yield, physicochemical/functional characteristics, physical stability and flowability of particles were affected by the type and composition of carriers. FTIR results indicated the placement of phenolic compounds in the carrier matrix. The SEM images also showed the morphological changes of particles (especially the size, indentation and surface shrinkage) under the influence of various carriers. Microencapsulated powders formulated using MD-HWPC showed the highest values of TPC, DPPH, and ABTS and a lighter color which determined the suitability of this wall material (due to the improvement of surface activity and emulsifying properties of protein as a result of partial enzymatic hydrolysis) to protect the antioxidant properties of GBLE during spray-drying, improving the production yield and preserving physical and functional characteristics of the encapsulated powders.

Effects of ultrasound assisted cell wall disruption on physicochemical properties of camellia bee pollen protein isolates

Camellia bee pollen protein isolates were extracted by cell wall disruption using ultrasonication, freeze-thawing, enzymatic hydrolysis, and their combinations. The effects of these methods on microstructure of cell wall, protein release, protein yield, physiochemical properties and structure of proteins were investigated. As compared with physical treatments (ultrasonication, freeze-thawing and their combination), the enzymatic hydrolysis significantly improved the yield of proteins, because it not only promoted the release of proteins from the inside of pollen, but also released proteins in pollen wall. The proteins extracted by enzymatic hydrolysis method also exhibited better solubility, emulsifying and gelation properties due to the partial hydrolysis of proteins by protease. In addition, when ultrasound was combined with freeze-thawing or enzymatic hydrolysis, it could further improve the yield of proteins and the functional properties of proteins, which was mainly related to the changes of protein structure induced by cavitation effect of ultrasound.

Extraction, microencapsulation, and application of anthocyanins from juçara palm fruit (Euterpe edulis Mart.): enhancement of natural pigment

The Juçara fruit (Euterpe edulis Martius) has been progressively standing out for presenting significant biological and nutritional activity. Its functional characteristics are related to its high content of anthocyanins, which, when isolated, are highly unstable, limiting their applications. The present research proposed to obtain an anthocyanin-rich extract from the juçara pulp, microencapsulate it with the maltodextrin and beta-cyclodextrin (beta-CD) matrices and evaluate the stability of the microencapsulated anthocyanins against light, pH, and milk development fermented. The use of encapsulating agents brought the anthocyanins significant thermal and light stability, in addition to intensifying their colors in a broader pH range. The FTIR-ATR techniques and the thermal analyzes of DSC and TGA showed that there was no molecular inclusion between the anthocyanins in the extract and beta-CD, but there was a physical interaction with the maltodextrin. In the development of fermented milk, the use of maltodextrin showed better product color stability. Therefore, anthocyanin microencapsulation processes can contribute to the development of innovative, more stable, and effective commercial food products.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05623-w.

Purification and characterization of antioxidant peptides from hairtail surimi hydrolysates and their effects on beef color stability

The antioxidant peptides extracted from plants or animals have shown great potential in preventing food quality deterioration caused by oxidization. Here, peptide fractions obtained from hairtail surimi hydrolysates (HSH) were investigated for structure and color-protective effect. The results showed the <3 kDa fraction obtained from HSH by ultrafiltration could be separated into five major fractions (A-E) by gel chromatography, among which fraction A possessed the highest antioxidant activities. This fraction A could be further separated into two fractions (A₁ and A₂ ) by the reversed-phase high-performance liquid chromatography, and fraction A₂ with lower α-helix content exhibited the higher antioxidant activities. The amino acids sequence of fraction A₂ was identified as DLYANTVLSGGTTMYPGIADR (2214.0627 Da). The synthetic peptide with this sequence was also found to exhibit obvious antioxidant activity. Moreover, both HSH, fractions A₁ and A₂ , and synthetic peptide demonstrated color-protective effects during the beef preservation. Taken together, the results obtained showed that the natural antioxidant peptides could be isolated from HSH, which can be used in meat preservation for inhibiting color deterioration. PRACTICAL APPLICATION: This study demonstrated the potential of hairtail surimi hydrolysates (HSH) as a source of antioxidant peptides. Furthermore, these antioxidant peptides purified from HSH exhibited the potential for prevention of beef color deterioration of beef, providing a potential application for meat preservation. Particularly, using the antioxidant peptides sourced from fish surimi for meat preservation may not only ease the safety concerns about artificial preservatives but also create a unique selling proposition, especially in far eastern Asian countries, since consumers in these countries believe "umami" is the combination of "fish" and "meat."

Spray drying encapsulation of bioactive compounds within protein-based carriers; different options and applications

Spray-drying is known as a common and economical technique for the encapsulation of various nutrients and bioactive compounds. However, shear and thermal tensions during atomization and dehydration, as well as physicochemical instability during storage, result in a loss of these compounds. As a solution, bioactives are stabilized into different carriers, among which proteins and peptides are of particular importance due to their functional properties, surface activity, and film/shell formability around particles. Given the importance of stabilization of bioactive compounds during spray drying, this paper focuses on the role of composition and type of carriers, as well as the characteristics and efficiency of various protein-based carriers in the encapsulation and maintaining of physicochemical, structural, and functional properties, along with biological activity of bioactive compounds (e.g., oleoresins, sterols, polyphenols, anthocyanins, carotenoids, probiotics, and peptides), and nutrients (e.g., vitamins, fatty acids and minerals) alone or in combination with other biopolymers.