Microencapsulation of anthocyanin-rich black soybean coat extract by spray drying using maltodextrin, gum Arabic and skimmed milk powder

Optimizing prodigiosin nanoencapsulation in different wall materials by freeze drying: Characterization and release kinetics

Prodigiosin, a microbial pigment, was produced using Serratia marcescens and encapsulated with β-cyclodextrin (BCD), maltodextrin (MD), gum Arabic (GA), and soy protein isolate (SPI) to enhance stability and bioavailability. Emulsions were prepared by dissolving wall materials (5 % w/v) in water, mixing with prodigiosin in ethanol (1:1), and adding Tween 80 as an emulsifier. The mixture was ultrasonicated, homogenized, and freeze-dried to form nanoparticles. Encapsulation efficiencies were 81.15 % (PBCDN), 76.93 % (PMDN), 89.15 % (PGAN), and 85.22 % (PSPIN). Particle size ranged from 115.63 to 181.42 nm, with PGAN having the largest size. FTIR confirmed successful encapsulation, while DSC indicated enhanced thermal stability, particularly in GA-based nanoparticles. In vitro release studies showed controlled release, with PGAN exhibiting the slowest release in gastric conditions. These results suggest GA is the most effective wall material for improving prodigiosin stability and controlled release for food, pharmaceutical, and cosmetic applications.

Utilization of Yeast Cells as Alternative Carriers in the Microencapsulation of Black Chokeberry (Aronia melanocarpa) Phenolic Extract

The structure of yeast cells, which are rich in bioactive compounds, makes them an attractive encapsulation vehicle due to their antioxidant, antibacterial, and antimutagenic properties. In this study, black chokeberry extract was encapsulated with different wall materials (maltodextrin, gum arabic, mixture of maltodextrin and gum arabic, plasmolyzed yeast, and non-plasmolyzed yeast) by freeze-drying. While the highest encapsulation efficiency was obtained with maltodextrin (98.82%), non-plasmolyzed yeast (86.58%) emerged as a viable alternative to gum arabic. The largest particle size was observed in plasmolyzed yeast microcapsules. Yeast-coated capsules exhibited a spheroidal morphology. Differential Scanning Calorimetry revealed high thermal stability for all microcapsules, with the gum arabic-coated microcapsules demonstrating the greatest stability. After the simulated gastric and intestinal fluid treatment, plasmolyzed yeast provided the highest retention, with 63.45% and 77.55% of phenolics, respectively. The highest 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activities were found in yeast microcapsules, with no significant difference between them. In 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) scavenging activity, the least loss (approximately 10%) was observed in non-plasmolyzed yeast samples after intestinal digestion. These results showed that yeast can be used as an alternative coating material in the encapsulation of phenolics, and it contributes to the bioavailability of microcapsules with its protective effect during digestion.

Effect of maltodextrin and Persian gum as wall materials and tannic acid as copigment on some properties of encapsulated sour cherry anthocyanin microcapsules

Due to the instability of anthocyanins, their application as natural colorants is limited. To improve their stability, anthocyanins extracted from sour cherry were copigmented with tannic acid at varying molar ratios. The optimal anthocyanin:copigment molar ratio was determined to be 1:0.25. Subsequently, both non-copigmented and copigmented anthocyanins (using the optimal tannic acid molarity) were spray-dried with either maltodextrin alone (T1 and T2) or a combination of maltodextrin and Persian gum (T3 and T4). The anthocyanin retention in T2 and T4 was approximately 53 % and 38 %, respectively, which were higher than in the non-copigmented samples. All powders demonstrated high encapsulation efficiency (>90.37 %). Stability tests on the anthocyanins conducted over 28 days indicated that light exposure had no effect on the reduction of anthocyanin content when maltodextrin was used. Thus, the copigmentation of anthocyanins with tannic acid, combined with encapsulation in maltodextrin, presents a promising method for producing a stable natural colorant.

Efficiency of freeze- and spray-dried microbial preparation as active dried starter culture in kombucha fermentation

BACKGROUND

Kombucha is a widely consumed fermented beverage produced by fermenting sweet tea with a symbiotic culture of bacteria and yeast (SCOBY). The dynamic nature of microbial communities in SCOBY may pose challenges to production scale-up due to unpredictable variations in microbial composition. Using identified starter strains is a novel strategy to control microorganism composition, thereby ensuring uniform fermentation quality across diverse batches. However, challenges persist in the cultivation and maintenance of these microbial strains. This study examined the potential of microencapsulated kombucha fermentation starter cultures, specifically Komagataeibacter saccharivorans, Levilactobacillus brevis and Saccharomyces cerevisiae, through spray-drying and freeze-drying.

RESULTS

Maltodextrin and gum arabic-maltodextrin were employed as carrier agents. Our results revealed that both spray-dried and freeze-dried samples adhered to physicochemical criteria, with low moisture content (2.18-7.75%) and relatively high solubility (65.75-87.03%) which are appropriate for food application. Freeze-drying demonstrated greater effectiveness in preserving bacterial strain viability (88.30-90.21%) compared to spray drying (74.92-78.66%). Additionally, the freeze-dried starter strains demonstrated similar efficacy in facilitating kombucha fermentation, compared to the SCOBY group. The observations included pH reduction, acetic acid production, α-amylase inhibition and elevated total polyphenol and flavonoid content. Moreover, the biological activity, including antioxidant potential and in vitro tyrosinase inhibition activity, was enhanced in the same pattern. The freeze-dried strains exhibited consistent kombucha fermentation capabilities over a three-month preservation, regardless of storage temperature at 30 or 4 °C.

CONCLUSION

These findings highlight the suitability of freeze-dried starter cultures for kombucha production, enable microbial composition control, mitigate contamination risks and ensure consistent product quality. © 2024 Society of Chemical Industry.

Fortification of milk powder with cashew apple juice using maltodextrin as a carrier material: A novel dairy recipe

Food preservation and fortification pose significant challenges in the fruit and dairy sectors, particularly in developing regions with limited infrastructure and rising production volumes. Cashew apples, rich in antioxidants such as vitamin C and polyphenolic compounds, often go to waste due to their high perishability. In Goa, India, these discarded fruits are used to produce "Feni," an alcoholic beverage, but broader utilization strategies are still needed. This study introduces a novel approach to extend the shelf life of dairy products like milk powder and enhance their nutritional content by fortifying it with cashew apple juice (CAJ) through spray drying. In order to reduce moisture content during spray drying and to obtain a free-flowing powder of the final product, maltodextrin was added. Maltodextrin alters the adhesive properties of the fruit juice droplets on surfaces and facilitates the formulation of free-flowing powder. The key parameters including solubility, bulk density, and glass transition temperature, along with structural analyses such as X-ray diffraction, field emission scanning electron microscope, and Fourier transform infrared spectroscopy, were evaluated to compare the fortified CAJ milk powder with its commercial counterparts. Experiments determined optimal spray-drying conditions, achieving a free-flowing powder at inlet and outlet temperatures of 140 and 60°C, respectively, with a 7% maltodextrin concentration (18 DE). The resulting milk powder displayed a Tg value of 76.7 ± 2.3°C, falling within the acceptable range of 65 to 98°C, demonstrating the feasibility of this fortification method based on the spray-drying process parameters.

Characterization of Marigold Flower (Tagetes erecta) Extracts and Microcapsules: Ultrasound-Assisted Extraction and Subsequent Microencapsulation by Spray Drying

Ultrasound-assisted extraction using response surface methodology was employed to extract marigold flower, resulting in a marigold flower extract (MFE) with elevated levels of total phenolic compounds (TPCs), total flavonoid content (TFC), total carotenoid content (TCC), and antioxidant activity, as assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays, under conditions of 40 °C temperature, 15 min extraction time, and 68% ethanol concentration. The MFE was subsequently encapsulated using spray drying with 45% maltodextrin (MD) (MFE-MD; 1:1, 1:2) and 20% gum arabic (GA) (MFE-GA; 1:2, 1:3). The MD (1:2 ratio) sample showed the highest encapsulation yield, while the 45% MD (1:1 ratio) sample exhibited the highest encapsulation efficiency (p ≤ 0.05). Samples containing 45% MD (1:1 ratio) and 20% GA (1:2 ratio) had the highest moisture content, with the 45% MD (1:1 ratio) sample showing the lowest water activity (p > 0.05). These samples also displayed higher L* and a* values compared to the 20% GA samples, which had increased b* values (p ≤ 0.05). Micrographs of the 20% GA (1:3 ratio) and 45% MD (1:2 ratio) samples revealed spherical shapes with smooth surfaces. The 20% GA (1:2 ratio) microcapsules exhibited the highest total phenolic content (TPC) among the samples (p ≤ 0.05). Thus, ultrasound-enhanced extraction combined with response surface methodology proved effective in producing functional food ingredients from plants.

Encapsulation of felty germander (Teucrium polium L.) extract using the freeze-drying method

Extracts with antimicrobial and antioxidant properties are limited in their application in food products due to their inability to withstand harsh environmental conditions, such as high temperatures and oxygen exposure. Therefore, the present study investigated the nanoencapsulation of Teucrium polium L. extract using the freeze-drying method to facilitate its application and protection against environmental factors. In this regard, an emulsion containing Teucrium polium L. extract at concentrations of 10%, 20%, and 30% and a mixture of maltodextrin/Persian gum in three ratios of 1:2, 1:1, and 2:1 as the coating wall were produced and then dried in a freeze dryer. In the following, the properties of emulsions and produced nanocapsules were studied. According to the results, emulsions with high amounts of Persian gum showed more stability, zeta potential, and viscosity. However, their particle size and polydisparity index were lower than those of other emulsions. As the extract concentration increased, there was a decrease in stability, zeta potential, and viscosity, accompanied by an increase in particle size and polydispersity index. Concurrently, elevated concentrations of maltodextrin, Persian gum, and extract resulted in higher humidity, density, encapsulation efficiency, and antioxidant activity of the capsules. The most optimal properties of emulsions and nanocapsules were achieved at the 10% concentration of Teucrium polium L. extract and the 1:1 ratio of maltodextrin/Persian gum mixture as the wall material. It is noteworthy that the release rate of phenolic compounds reached its maximum value (88%) after 60 days.

Development and Characterization of Microparticles with Actinidia arguta Leaves Extract by Spray-Drying: A New Mind-Set Regarding Healthy Compounds for Oral Mucositis

Actinidia arguta leaves have gained notoriety over the past years due to their rich bioactive composition with human pro-healthy effects, particularly in relation to antioxidants. Nevertheless, antioxidants are well known for their chemical instability, making it necessary to develop suitable delivery systems, such as microparticles, to provide protection and ensure a controlled release. The aim of this work was to produce polymeric particles of A. arguta leaves extract by spray-drying that may improve the oral mucositis condition. Microparticles were characterized by size, shape, antioxidant/antiradical activities, swelling capacity, moisture content, and effect on oral cells (TR146 and HSC-3) viability, with the aim to assess their potential application in this oral condition. The results attested the microparticles' spherical morphology and production yields of 41.43% and 36.40%, respectively, for empty and A. arguta leaves extract microparticles. The A. arguta leaves extract microparticles obtained the highest phenolic content (19.29 mg GAE/g) and antioxidant/antiradical activities (FRAP = 81.72 µmol FSE/g; DPPH = 4.90 mg TE/g), being perceived as an increase in moisture content and swelling capacity. No differences were observed between empty and loaded microparticles through FTIR analysis. Furthermore, the exposure to HSC-3 and TR146 did not lead to a viability decrease, attesting their safety for oral administration. Overall, these results highlight the significant potential of A. arguta leaves extract microparticles for applications in the pharmaceutical and nutraceutical industries.

Freeze-dried human milk microcapsules using gum arabic and maltodextrin: An approach to improving solubility

Human milk (HM) is essential for newborns' food, but its low storage stability is a limiting factor so that microencapsulation may stabilize and protect compounds sensitive to degradation. This study investigated the action of maltodextrin and gum arabic on freeze-dried HM concerning its quality and solubility. Microencapsulation was evidenced by morphology, and all samples presented high encapsulation efficiency (>85 %), proving to be an efficient process. Furthermore, specific signals in the Fourier-Transform Infrared (FTIR) spectra indicate the interactions between the coating materials and the HM matrix. Gum arabic improved the reconstitution properties of freeze-dried HM (higher solubility, 3 % on average, and lower dissolution time, around 80 %), elucidating its high stabilization capacity, even at low concentrations (5 and 10 %). Despite the best results reached by gum arabic, the addition of maltodextrin proved effective; in other words, its low stabilization capacity enables combinations with gum arabic. A lower polidispersibility (difference of 20 % between samples: control and containing gum arabic) was also observed, which means that the encapsulated samples were more homogeneous. Therefore, through the analysis performed, we recommend using gum arabic alone or with maltodextrin to obtain HM microcapsules with a good quality of reconstitution.

Encapsulation of Bilberry Extract with Maltodextrin and Gum Arabic by Freeze-Drying: Formulation, Characterisation, and Storage Stability

Anthocyanins are polyphenolic plant pigments associated with antioxidant and health-promoting properties. However, their application in the food industry is limited due to their poor stability. The purpose of this study was to encapsulate anthocyanin-rich bilberry (Vaccinium myrtillus L.) extract by freeze-drying and to investigate the effects of different wall materials and extract contents on the physicochemical and bioactive properties of the obtained encapsulates. Ethanolic bilberry extract was encapsulated with the use of maltodextrin (16.5–19.5 DE) (MD), gum Arabic (GA), and their combination in a 1:1 w/w ratio (MIX). Bilberry solids to wall material ratios were examined at 20:80, 30:70, and 40:60. All encapsulates showed an attractive red colour and low water activity values (aw ≤ 0.3) that indicated a low risk of microbial spoilage. In general, the biggest losses of total phenolic compounds and anthocyanins during three-week storage in the dark and at room temperature (20 ± 2 °C) were detected in the case of encapsulates with a higher content of bilberry extract (MIX30 and MIX40, and GA30 and GA40, respectively). The use of maltodextrin provided the best protection to bilberry anthocyanins during forced storage. Overall, the obtained encapsulates show suitable potential for the development of food products with added nutritional benefits.

Phenolic profile and antioxidant activity of free/bound phenolic compounds of sesame and properties of encapsulated nanoparticles in different wall materials

This study aimed to evaluate the antioxidant activity of free and bound flavonoid or phenolic compounds extracted from the sesame seed (Oltan and Yekta varieties) as natural antioxidants and to demonstrate the properties of nanoparticles. The total phenolic content (TPC) of Oltan was higher (864.70 mg GAE/100 g seed) than that of Yekta (629.23 mg GAE/100 g seed). Oltan took up higher amounts of free (516.86 mg GAE/100 g seed) and bound (347.83 mg GAE/100 g seed) phenolics than Yekta. Also, the Yekta variety exhibited lower amounts of free (45.89 mg CE/100 g seed) and bound flavonoids (21.51 mg CE/100 g seed) and the total flavonoid content (TFC) (67.40 mg CE/100 g seed). Chlorogenic acid was the major phenolic compound present in the sesame seed. In both the DPPH and ferric reducing antioxidant power (FRAP) assays, the highest antioxidant activity was observed in the Oltan variety. Free phenolics showed the highest antioxidant activity, followed by bound phenolics, free and bound flavonoids. Therefore, free phenolics of the Oltan variety were encapsulated in Portulaca oleracea and Trigonella foenum-graecum seed gums. All nanoparticles showed nanometric size from 236.1 to 680.7 nm, negative zeta potential from -35.4 to -18.3 mV, high encapsulation efficiency from 61.35% to 74.49%, and desirable polydispersity index (PDI) between 0.315 and 0.332. Higher release of phenolics and sedimentation rate were observed in phenolic compounds encapsulated in Khorfeh and Shanbalileh, respectively. The gradual release of phenolic compounds, as well as sedimentation rate of composite coating during 40 days of storage, demonstrated that nanoencapsulated phenolics of sesame within the composite gum coating could be used as natural antioxidants in food systems.

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.

Effects of organic solvent on functional properties of defatted proteins extracted from Protaetia brevitarsis larvae

This study investigated the effect of aqueous fat separation and defatting using organic solvents (99% methanol, ethanol, and n-hexane) on the characteristics and functionality of proteins extracted from Protaetia brevitarsis. The defatting efficiency, amino acid composition, protein solubility, and technical properties were the highest when proteins were defatted using n-hexane. Proteins defatted using ethanol were similar in foam capacity and emulsifying capacity. Surface hydrophobicity decreased when using organic solvents, and excessive fat content disrupted the functional properties of the extracted proteins. Proteins extracted using the different solvents displayed different pH values. The pH of the aqueous extract was the lowest. CIE L* a* b* color values also differed using the different extraction methods. Although n-hexane might be the most efficient solvent for defatting the proteins extracted from edible insects, ethanol could also be used to obtain similar foam and emulsifying capacities.

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.

Development of Health Products from Natural Sources

BioActive Compounds (BACs) recovered from food or food by-product matrices are useful in maintaining well being, enhancing human health, and modulating immune function to prevent or to treat chronic diseases. They are also generally seen by final consumers as safe, non-toxic and environment-friendly. Despite the complex process of production, chemical characterization, and assessment of health effects, BACs must also be manufactured in stable and bioactive ingredients to be used in pharmaceutical, food and nutraceutical industry. Generally, vegetable derivatives occur as sticky raw materials with pervasive smell and displeasing flavor. Also, they show critical water solubility and dramatic stability behavior over time, involving practical difficulties for industrial use. Therefore, the development of novel functional health products from natural sources requires the design of a suitable formulation to delivery BACs at the site of action, preserve stability during processing and storage, slow down the degradation processes, mask lousy tasting or smell, and increase the bioavailability, while maintaining the BACs functionality. The present review focuses on human health benefits, BACs composition, and innovative technologies or formulation approaches of natural ingredients from some selected foods and by-products from industrial food transformations.