Characterization of Starmerella bombicola sophorolipid microcapsules obtained via spray drying

Microencapsulation of fingered citron extract with gum arabic, modified starch, whey protein, and maltodextrin using spray drying

Pomegranate seed oil (PSO) is rich in bioactive compounds and is susceptible to oxidation. This research sought to encapsulate PSO in conventional and Pickering emulsions using whey protein isolate (WPI) microgels, WPI in its natural form, gum Arabic (GA), and WPI combinations with GA, maltodextrin (MD), and modified starch (Capsul®) as aqueous phase/emulsifier followed by spray drying. Emulsions with 1.39–2.55 μm droplet size, low viscosity (1.47–3.96 mPa s), and final interfacial tensions of 4.21–9.97 mN m−1 were obtained. All formulations were stable with the Turbiscan stability index between 4.57% and 12.95% at 24 h. Emulsions resulted in particles with encapsulation efficiency and yield of 56.28–73.83% and 28.07–93.99%, respectively. PSO powders had small particle sizes (9.86–22.60 μm), high glass transition temperature (103.24–121.62 °C), and oxidative stability index (OSI) of 2.71 h and in the range of 4.11–21.23 h for non-encapsulated and encapsulated PSO, respectively. All formulations promoted the oil oxidative protection when compared with the non-encapsulated one. Treatments presented feasible values of Aw, moisture, solubility, and hygroscopicity for handling and storage of the powders. WPI, WPI:Capsul®, and Pickering treatments promoted greater protection of the encapsulated oil; however, the combination of WPI with modified starch was considered the best wall material, allowing protection of PSO and future applications in the food industry.

Sappan wood (Caesalpinia sappan L.) heartwood contains phenolic compounds that require protection during storage due to its susceptibility to light, moisture, and oxygen. This study examines the microencapsulation of sappan wood extract using spray drying with various wall materials: maltodextrin (MD), modified starch (MS), gum arabic (GA), and their mixtures. Seven combinations of wall materials were tested. Spray drying was conducted at an inlet temperature of 150°C and a feed flow rate of 4 mL/min. Microcapsules were evaluated for yield, density, moisture content, encapsulation efficiency, particle size distribution, and morphology. Yields ranged from 43.84% to 69.62%, with moisture content below 6%. The total phenolic extract was 64.22 mg GAE/g extract with phenolic retention in microcapsules ranging from 16.56% to 37.09%. MD, as a single-wall material, produced microcapsules with the smallest particle size (19.765 mm) but the highest span number (2.889). The release kinetics fitted well with the Korsmeyer-Peppas and Weibull models. A 50:50 combination of GA and MD provided the highest encapsulation efficiency (67.16%). The findings suggest that the blend of MD and GA optimizes the microencapsulation of sappan wood extract.

Basil (Ocimum basilicum L.) essential oil (BEO) draws attention for its phenolic acid content which causes it to be used as a medicinal agent and food additive. However, its vulnerability to environmental and technological factors can be an obstacle to its implementation in industry and, at this point, encapsulation technology is utilized. The objective of this study was to encapsulate BEO using a spray drying technique to extend its shelf life, and to evaluate the influence of different wall material formulations on the properties of the BEO microcapsules. Gum Arabic (GA), maltodextrin (MD), and whey protein isolate (WPI) were used as wall materials and four different formulations were studied: GA, GA:WPI (1:1, w/w), GA:WPI:MD (1:1:1, w/w), and WPI:MD (1:1, w/w). The GA, GA:WPI, and GA:WPI:MD emulsions displayed shear thinning behavior (pseudoplastic, n < 1) while the WPI:MD emulsion behaved as a Newtonian fluid (n = 1). The GA (0.21 µm) and WPI:MD (0.25 µm) emulsions, having smaller droplets, exhibited no creaming. Powder recovery values of the BEO microcapsules ranged from 65.92% to 76.39%. The encapsulation efficiency of the microcapsules varied between 82.34% and 87.19%; the highest value was determined for the GA:WPI:MD microcapsules. Optimal thermal stability and higher Tg values were obtained for the GA:WPI and GA:WPI:MD formulations. The ternary combination also had the highest in vitro eugenol release (58.97%) in ethanol. Finally, the GA:WPI:MD formulation demonstrated a high product yield and encapsulation efficiency with better physicochemical properties for encapsulation of BEO.

Microencapsulation of yerba mate extract by spray-drying technique: Impact of polysaccharide mixtures on powder characteristics.

Encapsulation efficiency and oxidative stability of flaxseed oil microencapsulated by spray drying using different combinations of wall materials

Orange essential oil (OEO) was microencapsulated by complex coacervation using a whey protein isolate (WPI)–arabic gum (AG) system followed by spray drying, and it was compared with the conventional spray drying microencapsulation process using N-Lok starch as wall material. Complex coacervation between WPI and AG was characterized in terms of zeta potential and coacervation efficiency. Coacervated microcapsules with different core:wall (OEO:WPI–AG) ratio (1:1–1:4) were spray dried using 160 and 90 °C as inlet and outlet temperature, respectively. Maltodextrin DE10 was added to protect integrity of coacervated microcapsules during spray drying. The highest retention and encapsulation efficiency (53 and 46% respectively) were obtained for a core:wall ratio of 1:2. The WPI:AG system with core:wall ratio of 1:2 was spray dried using 140–220 °C and 80–120 °C as inlet and outlet temperatures respectively, and the results indicated that these inlet and outlet temperatures had no significant effect on retention and encapsulation efficiency. Microencapsulation by conventional spray drying at 200–120 °C as inlet and outlet temperatures, resulted in the highest retention and encapsulation efficiencies (79 and 73% respectively), which represents 25% higher than spray dried coacervated microcapsules. After 4 months of storage, the spray dried coacervated microcapsules showed a tenfold higher carvone concentration (indicator of degradation), than the conventional microencapsulated spray dried product.

Microencapsulation of juniper berry essential oil (Juniperus communis L.) by spray drying: microcapsule characterization and release kinetics of the oil

Background and ObjectivesThe aim of this study was to investigate the effect of incorporation of different plant‐based polysaccharides (pectin, maltodextrin (MD) and gum arabic (GA)) with pea protein isolate (PPI) to obtain maximum encapsulation efficiency (EE), gastrointestinal (GI) stability and yield of probiotic Lactobacillus casei through spray drying. Several characteristics of encapsulated vegan probiotic powders were evaluated including functional, structural, and thermal characteristics.FindingsThe results showed that the highest EE (93.9%) and in vitro GI stability (8.58 log CFU/mL) was obtained with the powder encapsulated with PPI + GA. Variation in particle size was observed for all the samples. Confocal laser micrographs and vital staining revealed the highest viability of probiotic L. casei cells that were obtained with those encapsulated in PPI + GA. Thermal properties showed that the incorporation of GA increased the glass transition temperature up to 189.2°C, which represented a higher thermal stability of the powder.ConclusionsPPI + GA coated powder was found with acceptable powder characteristics and maximum probiotic survivability.Significance and NoveltyIn this study, spray drying was used to encapsulate the probiotic bacteria which is a convenient and effective process for industrial applications. Characterization of the spray‐dried encapsulated probiotic powder has been done, which helps to understand the behavior of powder in terms of solubility, flowability, thermal stability, and probiotic viability. PPI was used as carrier material, which bridges the gap between already available spray‐dried products containing MD as carrier material, which could spike blood sugar levels if consumed over an extended period of time. As per the results, target product applications could include sports bars, cereals, and baking where dispersibility is not imperative.

Antioxidant compounds in food are generally less stable when applied to food, so technology is needed to help antioxidant compounds become more stable during storage, one of which is microencapsulation. The research aims to determine the effect of the wall material ratio and drying methods on the characteristics of Sardinella lemuru smart flavor microcapsules. The experimental design used was a two-factor Complete Random Design (CRD): ratio of wall materials (maltodextrin: Arabic gum) and drying methods (spray drying and freeze drying). The research showed that enzyme activity ranged from 14.81-52.64 U/mL; lightness 95.2-100; yield 4.00-17.19%; water content 2.26-9.15%; antioxidant activity 15.75-31.23%; encapsulation efficiency 69.06-78.47%. Microcapsules with the highest water content, lightness, antioxidant activity, and encapsulation efficiency were at the ratio wall materials (maltodextrin: Arabic gum) of 7:3 by spray drying, 9.15%, 100, 31.23%, and 78.47%. On the other hand, the highest yield (17.19%) was at the ratio wall materials (maltodextrin: Arabic gum) 8:2 by freeze-drying. The morphology of the microcapsules by spray drying is spherical, and freeze drying makes it flaky and sharp.

Application of yellow mustard mucilage in encapsulation of essential oils and polyphenols using spray drying

The most commonly-used and effective wall materials (WMs) for spray-dried microencapsulation of bioactive compounds are either costly, or derived from unsustainable sources, which lead to an increasing demand for alternatives derived from sustainable and natural sources, with low calories and low cost. Wood hemicelluloses obtained from by-products of forest industries appear to be attractive alternatives as they have been reported to have good emulsifying properties, low viscosity at high concentrations, high heat stability and low heat transfer. Here, we investigated the applicability of spruce galactoglucomannans (GGM) and birch glucuronoxylans (GX), to encapsulate flaxseed oil (FO, polyunsaturated fatty acid-rich plant based oil) by spray drying; and the results were compared to those of the highly effective WM, gum Arabic (GA). It was found that depending on solid ratios of WM:FO (1:1, 3:1 and 5:1), encapsulation efficiency of GGM was 88–96%, and GX was 63–98%. At the same encapsulation ratio, both GGM and GX had higher encapsulation efficiency than GA (49–92%) due to their ability to produce feed emulsions with a smaller oil droplet size and higher physical stability. In addition, the presence of phenolic residues in GGM and GX powders enabled them to have a greater ability to protect oil from oxidation during spray drying than GA. Physiochemical properties of encapsulated powders including thermal properties, morphology, molecular structure, particle size and water adsorption intake are also investigated. The study has explored a new value-added proposition for wood hemicelluloses which can be used as effective WMs in the production of microcapsules of polyunsaturated fatty acid-rich oils for healthy and functional products in food, pharmaceutical and cosmetic industries.

The main objective of this study was to evaluate the influence of the different wall material combinations on the microencapsulation of virgin coconut oil (VCO) by spray drying. Maltodextrin (MD) and sodium caseinate (SC) were used as the basic wall materials and mixed with gum Arabic (GA), whey protein concentrate (WPC) and gelatin (G). The stability, viscosity and droplet size of the feed emulsions were measured. MD:SC showed the best encapsulation efficiency (80.51%) and oxidative stability while MD:SC:GA presented the lowest encapsulation efficiency (62.93%) but better oxidative stability than the other two combinations. Microcapsules produced were sphere in shape with no apparent fissures and cracks, low moisture content (2.35–2.85%) and high bulk density (0.23–0.29 g/cm 3 ). All the particles showed relatively low peroxide value (0.34–0.82 meq peroxide/kg of oil) and good oxidative stability during storage. MD:SC:GA microencapsulated VCO had the highest antioxidant activity in both of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) (0.22 mmol butylated hydroxyanisole (BHA)/kg of oil) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays (1.35 mmol trolox/kg of oil).

The encapsulation of curcumin in combination with spray drying is one of the techniques capable of improving its stability. This process is highly dependent on coating material. Natural biopolymers, such as maltodextrin (MD) and gum Arabic (GA), have been reported to show curcumin protection as coating material. Konjac glucomannan hydrolysate (KGMH) is a functional food ingredient with potential as a coating material. Applying the combination of these biopolymers to encapsulate curcumin should improve the properties of microcapsules. This study investigated the effects of combining coating materials (KGMH, MD, and GA) on bioaccessibility and encapsulation efficiency (EE) of spray-dried curcumin microcapsules. The initial emulsion (mean particle size, polydispersion index, ζ-potential, and viscosity) and microcapsule (yield, water activity, moisture content, color, solubility, hygroscopicity, size, morphology, Fourier-transform infrared (FT-IR) spectra, and antioxidant activity) properties were also characterized. Each coating material contributed to both the advantages and disadvantages characters of the microcapsules. The higher binding of surface-active GA generated a higher EE but lower bioaccessibility. The opposite trend was observed in MD-coated microcapsules. KGMH and MD provided comparable bioaccessibility, but the higher EE of KGMH was evidenced. All coating materials produced curcumin microcapsules with statistically equal ferric-reducing antioxidant power. The combined MD, GA, and KGMH in a similar ratio was the best formulation that produced microcapsules with a good bioaccessibility (78.83%) and EE (85.52%) profile. PRACTICAL APPLICATION: This study on curcumin encapsulation could benefit the nutraceutical and functional food industry by creating stable, bioaccessible curcumin supplements with enhanced antioxidant properties. Using a blend of natural coating materials, such as konjac glucomannan hydrolysate, maltodextrin, and gum Arabic, these microcapsules could improve curcumin's effectiveness in health products, potentially increasing consumer access to curcumin's health benefits in a stable, easy-to-use form.

Tuna oil rich in omega-3 fatty acids was microencapsulated in whey protein isolate (WPI)-gum arabic (GA) complex coacervates, and subsequently dried using spray and freeze drying to produce solid microcapsules. The oxidative stability, oil microencapsulation efficiency, surface oil and morphology of these solid microcapsules were determined. The complex coacervation process between WPI and GA was optimised in terms of pH, and WPI-to-GA ratio, using zeta potential, turbidity, and morphology of the microcapsules. The optimum pH and WPI-to-GA ratio for complex coacervation was found to be 3.75 and 3 : 1, respectively. The spray dried solid microcapsules had better stability against oxidation, higher oil microencapsulation efficiency and lower surface oil content compared to the freeze dried microcapsules. The surface of the spray dried microcapsules did not show microscopic pores while the surface of the freeze dried microcapsules was more porous. This study suggests that solid microcapsules of omega-3 rich oils can be produced using WPI-GA complex coacervates followed by spray drying and these microcapsules can be quite stable against oxidation. These microcapsules can have many potential applications in the functional food and nutraceuticals industry.