Microencapsulation of linseed oil by spray drying for functional food application

Stability and in vitro release behaviour of encapsulated omega fatty acid-rich oils in lentil protein isolate-based microcapsules

The objective of this study was to investigate the use of a lentil protein isolate-based microcapsule design as a platform for entrapping different types of omega fatty acid-rich oil (e.g. canola, fish and flaxseed oils) and to characterise differences in the physical properties (e.g. moisture content, water activity, colour, wettability, particle size, surface oil and entrapment efficiency), storage stability and in vitro release behaviour of the entrapped oils. All microcapsules displayed similar physical properties regardless of the core material. Free fatty acid content, peroxide value, 2-thiobarbituric acid reactive substances and accelerated oxidation test were investigated between the free and encapsulated oils to determine protective effects from microencapsulation and found the wall material provided the greatest protective effect to the fish oils relative to the others. Based on an in vitro release assay, it was proposed that different intrinsic properties of fatty acids (e.g. polarity, conformation, chain length and number of double bonds) led to different release properties under simulated conditions. For instance, more encapsulated canola oil (∼8.9%) was released within simulated gastric fluid, whereas more encapsulated fish oil (∼73.4%) was released within simulated gastrointestinal fluids. Overall, the capsule design used in this study could be potentially used as a universal platform to deliver more healthy oils.

Optimization of Rice Bran Oil Encapsulation Using Jackfruit Seed Starch – Whey Protein Isolate Blend as Wall Material and Its characterization

Response surface methodology (RSM) was used to optimize rice bran oil encapsulation using jackfruit seed starch – whey protein isolate blend as wall material by spray drying technique. Oil concentration (20, 25 and 30 %), wall material (Jackfruit seed starch & whey protein isolate) starch-protein ratio (1:1, 3:1 and 5:1) and spray drying inlet air temperature (140, 150 and 160 °C) were considered as process variables for optimization. A three-factor, three-level Box-Behnken design of RSM was used to conduct the experiments with the aim of maximizing encapsulation efficiency and minimizing peroxide value in the encapsulated powder. A polynomial regression model was fitted using design expert software, and the optimum conditions obtained were 20 % oil concentration, 3:1 starch-protein ratio and 140 °C spray drying inlet air temperature. The encapsulated rice bran oil powers obtained at optimized conditions offered 85.90 % of encapsulation efficiency and 1.18 meq/kg oil of peroxide value. The characterization study revealed that powder particles size (diameter) varied from 3.40 to 300.51 µm and most of the particles were smooth spheres with little appendages.

Microencapsulation of palm oil by complex coacervation for application in food systems

This study aimed at microencapsulating palm oil, containing high carotenoid content, with chitosan/xanthan and chitosan/pectin, using the complex coacervation method, followed by atomization and lyophilization. The DSC technique was used to confirm the encapsulation. The atomized microparticles had spherical shape and irregular size, and the lyophilized microparticles had irregular shape and size. Lyophilization resulted in lower carotenoids losses, and higher yield and encapsulation efficiency. In addition, the release profile in both water and gastrointestinal fluid was satisfactory. Prior to their application in food, a greater percentage of carotenoids was released in the fluid that simulates gastrointestinal conditions; however, the compounds were degraded after their release. In this case, the chitosan/pectin microparticles showed the best release profile. After processing, the release was lower and the released compounds were not degraded. Thus, the chitosan/xanthan microparticles showed the best potential for practical application, particularly, in yogurt preparation.

Quality evaluation of peony seed oil spray-dried in different combinations of wall materials during encapsulation and storage

This study aimed at evaluating the performance of peony seed oil microencapsulated by spray drying during encapsulation and storage. Four different combinations of gum arabic (GA), corn syrup (CS), whey protein concentrate (WPC) and sodium caseinate (CAS) were used to encapsulate peony seed oil. The best encapsulation efficiency was obtained for CAS/CS followed by the CAS/GA/CS combination with the encapsulation ratio of 93.71 and 92.80 %, respectively, while the lowest encapsulation efficiency was obtained for WPC/GA/CS (85.96 %). Scanning electron microscopy and confocal laser scanning microscopy revealed that the particles were spherical in shape and did not exhibit apparent cracks or fissures, and gum arabic was uniformly distributed across the wall of the microcapsules. Oxidative stability study indicated that the CAS/GA/CS combination presented the best protection against lipid oxidation and the smallest loss of polyunsaturated fatty acid content among all of the formulas as measured by gas chromatography. Therefore, CAS/GA/CS could be promising materials encapsulate peony seed oil with high encapsulation efficiency and minimal lipid oxidation.

Fortification of dahi (Indian yoghurt) with omega-3 fatty acids using microencapsulated flaxseed oil microcapsules

The objective of the study was to develop and characterize omega-3 dahi (Indian yoghurt) through fortification of microencapsulated flaxseed oil powder (MFOP). Four different formulations of MFOP were fortified in dahi @ 1, 2 and 3 % levels and the level of addition was optimized on the basis of sensory scores. Dahi fortified at 2 % level was observed comparable to control, which was further studied for titratable acidity, syneresis, firmness, stickiness, oxidative stability (peroxide value), α-linolenic acid (ALA, ω-3) content and sensory attributes during 15d of storage. MFOP fortified dahi showed significantly (p < 0.05) higher acidity and percent syneresis after 12d of storage. However, peroxide value remained well below (~0.41) to the maximum permissible limit (5 meq peroxides/kg oil) prescribed by Codex Alimentarius Commission (1999). Gas-liquid chromatography profile showed ~21 % decrease in ALA content in fortified dahi after 15d of storage. Overall, it can be concluded that flaxseed oil microcapsules could be successfully incorporated in dahi; which could serve as a potential delivery system of omega-3 fatty acids.

Microencapsulation of Nigella sativa oleoresin by spray drying for food and nutraceutical applications

Oleoresin of Nigella sativa L. (Black cumin) was obtained from the seeds using hexane extraction at room temperature. The oleoresin was emulsified in an aqueous solution containing gum Arabic/maltodextrin (1:1 w/w) and then encapsulated in powder form by spray drying. The characteristics of the obtained powder including moisture content, bulk density, wettability, morphology, encapsulation efficiency were evaluated. The effect of the spray drying on the chemical composition of the volatile oil fraction of N. sativa oleoresin was also evaluated using gas chromatographic-mass spectroscopic analysis. Results indicated that the encapsulation efficiency of the whole oleoresin in the powder can range from 84.2±1.5% to 96.2±0.2% depending on the conditions of extracting the surface oil from the powder. On the other hand the encapsulation efficiency of the volatile oil fraction was 86.2% ±4.7. The formulated N. sativa L. oleoresin powder can be used in the fortification of processed food and nutraceuticals.

Elaboration of microparticles of carotenoids from natural and synthetic sources for applications in food

Carotenoids are susceptible to isomerization and oxidation upon exposure to oxygen, light and heat, which can result in loss of color, antioxidant activity, and vitamin activity. Microencapsulation helps retain carotenoid stability and promotes their release under specific conditions. Thus, the aim of the study was to encapsulate palm oil and β-carotene with chitosan/sodium tripolyphosphate or chitosan/carboxymethylcellulose and to assess the performance of these microparticles in food systems by analyzing their release profile under simulated gastric and intestinal conditions. Encapsulation efficiency was greater than 95%, and the yield of microparticles coated with chitosan/sodium tripolyphosphate was approximately 55%, while that of microparticles coated with chitosan/carboxymethylcellulose was 87%. Particles encapsulated with chitosan/carboxymethylcellulose exhibited ideal release behavior in water and gastric fluid, but showed low release in the intestinal fluid. However, when applied to food systems these particles showed enhanced carotenoid release but showed low release of carotenoids upon storage.

One-step fabrication of silica colloidosomes with in situ drug encapsulation

In situ modification, drug encapsulation and fabrication of hollow silica colloidosomes in microfluidic device.

Development of stable flaxseed oil emulsions as a potential delivery system of ω-3 fatty acids

The objective of the present study was to develop a stable flaxseed oil emulsion for the delivery of omega-3 (ω-3) fatty acids through food fortification. Oil-in-water emulsions containing 12.5 % flaxseed oil, 10 % lactose and whey protein concentrate (WPC)-80 ranging from 5 to 12.5 % were prepared at 1,500, 3,000 and 4,500 psi homogenization pressure. Flaxseed oil emulsions were studied for its physical stability, oxidative stability (peroxide value), particle size distribution, zeta (ζ)-potential and rheological properties. Emulsions homogenized at 1,500 and 4,500 psi pressure showed oil separation and curdling of WPC, respectively, during preparation or storage. All the combinations of emulsions (homogenized at 3,000 psi) were physically stable for 28 days at 4-7 ºC temperature and did not show separation of phases. Emulsion with 7.5 % WPC showed the narrowest particle size distribution (190 to 615 nm) and maximum zeta (ζ)-potential (-33.5 mV). There was a slight increase in peroxide value (~20.98 %) of all the emulsions (except 5 % WPC emulsion), as compared to that of free flaxseed oil (~44.26 %) after 4 weeks of storage. Emulsions showed flow behavior index (n) in the range of 0.206 to 0.591, indicating higher shear thinning behavior, which is a characteristic of food emulsions. Results indicated that the most stable emulsion of flaxseed oil (12.5 %) can be formulated with 7.5 % WPC-80 and 10 % lactose (filler), homogenized at 3,000 psi pressure. The formulated emulsion can be used as potential omega-3 (ω-3) fatty acids delivery system in developing functional foods such as pastry, ice-creams, curd, milk, yogurt, cakes, etc.

Prosopis alba exudate gum as excipient for improving fish oil stability in alginate-chitosan beads

The aim of the present work was to employ an exudate gum obtained from a South American wild tree (Prosopis alba), as wall material component to enhance the oxidative stability of fish oil encapsulated in alginate-chitosan beads. For this purpose, beads were vacuum-dried and stored under controlled conditions. Oxidation products, fatty acid profiles and lipid health indices were measured during storage. Alginate-chitosan interactions and the effect of gum were manifested in the FT-IR spectra. The inclusion of the gum in the gelation media allowed decreasing the oxidative damage during storage in comparison to the free oil and alginate-chitosan beads. The gum also improved wall material properties, providing higher oil retention during the drying step and subsequent storage. Fatty acids quality and lipid health indices were widely preserved in beads containing the gum. Present results showed a positive influence of the gum on oil encapsulation and stability, being the main mechanism attributed to a physical barrier effect.

The effect of partial-fat substitutions with encapsulated and unencapsulated fish oils on the technological and eating quality of beef burgers over storage

The effects of fat substitution (≤ 15%) with commercial encapsulated and unencapsulated fish oils on the technological and eating quality of beef burgers over storage [modified atmosphere packs (80% O2:20% CO2); constantly illuminated retail display at 4 °C; for 15 days] were studied using design of experiment (DOE). Burger formulations comprised beef shin (59.5%), salt (0.5%), vitamin E (0.015%) combined with varying levels of beef-fat/fish oils depending on the treatment. Increasing amounts of encapsulated and unencapsulated fish oils in burgers increased polyunsaturated fatty acid content (P < 0.001). Storage decreased (P < 0.001) a* values, which was in agreement with oxymyoglobin data. Vitamin E inclusion in burgers resulted in higher (P < 0.01) oxymyoglobin values. TBARS values increased (P < 0.001) over storage as expected. Fat substitution with unencapsulated oils increased cook loss (P < 0.001) and decreased hardness (P < 0.05) compared to other treatments. Optimisation predicted a burger formulation with 7.8% substitution in beef-fat with encapsulated fish oil. Panellists scored the optimised burger formulation (P < 0.05) lower than controls for overall acceptability.

Influence of Different Wall Materials on the Microencapsulation of Virgin Coconut Oil by Spray Drying

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/cm3). 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).

Microencapsulation of bioactives for food applications

The potential of microencapsulation to protect bioactive compounds ensuring bioavailability maintenance is proved but requires further studies on its applicability and incentives by regulatory agencies.

Spray Drying of Rhodomyrtus tomentosa (Ait.) Hassk. Flavonoids Extract: Optimization and Physicochemical, Morphological, and Antioxidant Properties

The optimal condition of spray drying purified flavonoids extract from R. tomentosa berries was studied by response surface methodology. The optimized condition for microencapsulation was of maltodextrin to gum Arabic ratio 1 : 1.3, total solid content 27.4%, glycerol monostearate content 0.25%, and core to coating material ratio 3 : 7, resulting in EE 91.75%. Prepared at the optimized condition, the flavonoids extract microcapsules (FEMs) were irregularly spherical particles with low moisture content (3.27%), high solubility (92.35%), and high bulk density (0.346 g/cm³). DPPH radical scavenging activity of FEMs was not decreased after spray drying (P > 0.05) and higher than those in citric acid and rutin at the same concentration. Moreover, FEMs effectively retarded the oxidation of fresh lard during the 10-day storage period compared with vitamin C, nonencapsulated flavonoids extract, and rutin. Therefore, FEMs produced at the optimized condition could be used as powder ingredients with antioxidant capacities.