Microencapsulation of casein hydrolysate by complex coacervation with SPI/pectin

The aim of this work was to encapsulate casein hydrolysate by complex coacervation with soybean protein isolate (SPI)/pectin. Three treatments were studied with wall material to core ratio of 1:1, 1:2 and 1:3. The samples were evaluated for morphological characteristics, moisture, hygroscopicity, solubility, hydrophobicity, surface tension, encapsulation efficiency and bitter taste with a trained sensory panel using a paired comparison test. The samples were very stable in cold water. The hydrophobicity decreased inversely with the hydrolysate content in the microcapsule. Encapsulated samples had lower hygroscopicity values than free hydrolysate. The encapsulation efficiency varied from 91.62% to 78.8%. Encapsulated samples had similar surface tension, higher values than free hydrolysate. The results of the sensory panel test considering the encapsulated samples less bitter (P < 0.05) than the free hydroly-state, showed that complex coacervation with SPI/pectin as wall material was an efficient method for microencapsulation and attenuation of the bitter taste of the hydrolysate. (C) 2009 Elsevier Ltd. All rights reserved.

Complex coacervation with whey protein isolate and gum arabic for the microencapsulation of omega-3 rich tuna oil.

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.

Optimisation of the microencapsulation of tuna oil in gelatin-sodium hexametaphosphate using complex coacervation.

The microencapsulation of tuna oil in gelatin-sodium hexametaphosphate (SHMP) using complex coacervation was optimised for the stabilisation of omega-3 oils, for use as a functional food ingredient. Firstly, oil stability was optimised by comparing the accelerated stability of tuna oil in the presence of various commercial antioxidants, using a Rancimat™. Then zeta-potential (mV), turbidity and coacervate yield (%) were measured and optimised for complex coacervation. The highest yield of complex coacervate was obtained at pH 4.7 and at a gelatin to SHMP ratio of 15:1. Multi-core microcapsules were formed when the mixed microencapsulation system was cooled to 5 °C at a rate of 12 °C/h. Crosslinking with transglutaminase followed by freeze drying resulted in a dried powder with an encapsulation efficiency of 99.82% and a payload of 52.56%. Some 98.56% of the oil was successfully microencapsulated and accelerated stability using a Rancimat™ showed stability more than double that of non-encapsulated oil.

Complex coacervation between flaxseed protein isolate and flaxseed gum

Flaxseed protein isolate (FPI) and flaxseed gum (FG) were extracted, and the electrostatic complexation between these two biopolymers was studied as a function of pH and FPI-to-FG ratio using turbidimetric and electrophoretic mobility (zeta potential) tests. The zeta potential values of FPI, FG, and their mixtures at the FPI-to-FG ratios of 1:1, 3:1, 5:1, 10:1, 15:1 were measured over a pH range 8.0-1.5. The alteration of the secondary structure of FPI as a function of pH was studied using circular dichroism. The proportion of a-helical structure decreased, whereas both β-sheet structure and random coil structure increased with the lowering of pH from 8.0 to 3.0. The acidic pH affected the secondary structure of FPI and the unfolding of helix conformation facilitated the complexation of FPI with FG. The optimum FPI-to-FG ratio for complex coacervation was found to be 3:1. The critical pH values associated with the formation of soluble (pHc) and insoluble (pHΦ1) complexes at the optimum FPI-to-FG ratio were found to be 6.0 and 4.5, respectively. The optimum pH (pHopt) for the optimum complex coacervation was 3.1. The instability and dissolution of FPI-FG complex coacervates started (pHΦ2) at pH2.1. These findings contribute to the development of FPI-FG complex coacervates as delivery vehicles for unstable albeit valuable nutrients such as omega-3 fatty acids.

Production of turmeric oleoresin microcapsules by complex coacervation with gelatin-gum arabic

Turmeric oleoresin is a colorant prepared by solvent extraction of turmeric (Curcuma longa L.). Curcumin, the major pigment present in turmeric, has been described as a potent antioxidant, anti-inflammatory and anticarcinogenic agent. Turmeric pigments are lipid soluble and water insoluble and are sensitive to light, heat, oxygen and pH, which can be overcome by microencapsulation of turmeric oleoresin. The aim of this work was to investigate microencapsulation of turmeric oleoresin by complex coacervation using gelatin and gum Arabic as encapsulants and freeze-drying as the drying method. The coacervation process was studied by varying the concentration of biopolymer solution (2.5, 5.0 and 7.5%) and the core material: total encapsulant ratio (25, 50, 75 and 100%). Microcapsules were evaluated for encapsulation efficiency, morphology, solubility and stability to light. Encapsulation efficiency ranged from 49 to 73% and samples produced with 2.5% of wall material and 100% core: encapsulant ratio showed better stability to light. © 2012 Wiley Periodicals, Inc.

Microencapsulation of lycopene by gelatin-pectin complex coacervation

The aim of this work was to produce and characterize microcapsules of lycopene and to evaluate their stability in comparison with free lycopene. An oily dispersion of lycopene was encapsulated by complex coacervation using gelatin and pectin. Samples were analyzed at four different pH values (3, 3.5, 4 and 4.5) and three proportions of core (25, 50 and 100%). The moisture, water activity, solubility, hygroscopicity, encapsulation efficiency and stability of lycopene microcapsules kept at 10 and 25C were determined. The amount of lycopene in the microcapsule did not have a significant (P < 0.05) effect on water activity, hygroscopic characteristics or the efficiency of microencapsulation. The degradation of lycopene was linear, with an average loss of 14% per week. Therefore, despite the formation of microcapsules and the high values of encapsulation efficiency, the encapsulation method and the wall materials used in this work did not provide effective protection of the lycopene from degradation during storage.

Whey protein and gum arabic encapsulated Omega-3 lipids. The effect of material properties on coacervation

The effect of material properties on complex coacervation of whey protein and gum Arabic from various sources was investigated. In this study, it was demonstrated that material properties of whey protein isolates and gum Arabic affect the complex coacervation process significantly. For whey protein, the coacervation capability could be correlated with their level of denaturation and calcium content. For gum Arabic, both material sources and salt content were found to be attributing factors to their coacervation capability. This study facilitated the development of Omega-3 lipids microcapsules with promising performances in certain food applications.

Studies on the formation of complex coacervates between chitosan and alginate during microparticles preparation

The formation of complex coacervates between chitosan and alginate was evaluated during microparticles formation. Mass ratio between polyelectrolytes and calcium chloride concentration were determinated by conductimetric analysis and by calcium ions quantification, respectively. Inert microparticles were prepared using a complex coacervation method in W/O emulsion and morphological analyses of microparticles were carried out. This method enabled the production of spherical particles, with slightly rough surface and narrow size distribution with maximal diameter of 10 μm.

Preparation and characterization of chia seed protein isolate-chia seed gum complex coacervates

Chia seed protein isolate (CPI) and chia seed gum (CSG) were extracted and complex coacervation between these two was studied. The pH and the CPI-to-CSG ratio were optimized to obtain the highest yield of complex coacervates underpinned by zeta potential and turbidity values. CPI-CSG complex coacervates were found to form primarily due to electrostatic interaction and remained stable within a pH range of 2.1-2.9 at ambient temperature. The optimum pH and CPI-to-CSG ratio for complex coacervation was found to be 2.7 and 6:1, respectively. Spray dried complex coacervate particles possessed smoother surface morphology compared to the freeze dried ones. CPI-CSG complex coacervates demonstrated better thermal stability as compared to that of individual CPI and CSG. The crosslinking of these complex coacervates by transglutaminase further improved their thermal stability. Therefore, the crosslinked CPI-CSG complex coacervates will be able to better protect the oxygen and heat sensitive food and pharmaceutical ingredients.

Microencapsulation of flaxseed oil in flaxseed protein and flaxseed gum complex coacervates

Flaxseed oil, a rich source of omega-3 fatty acids, was microencapsulated in a novel matrix formed by complex coacervation between flaxseed protein isolate (FPI) and flaxseed gum (FG). This matrix was crosslinking with glutaraldehyde. Liquid microcapsules with three core (oil)-to-wall ratios (1:2, 1:3 and 1:4) were prepared and spray-dried or freeze-dried to produce powders. The microencapsulation efficiency, surface oil, morphology and oxidative stability of these microcapsules were determined. The spray-dried solid microcapsules had higher oil microencapsulation efficiency, lower surface oil content, smoother surface morphology and higher oxidation stability than the freeze-dried microcapsules. The highest microencapsulation efficiency obtained in spray-dried microcapsules was 87% with a surface oil of 2.78% at core-to-wall ratio 1:4 and oil load 20%. The oxidation stability obtained from spray-dried microcapsules at core-to-wall ratio of 1:4 was nearly double that of the unencapsulated flaxseed oil.

Microencapsulation of chia seed oil using chia seed protein isolate-chia seed gum complex coacervates

Chia seed oil (CSO) microcapsules were produced by using chia seed protein isolate (CPI)-chia seed gum (CSG) complex coacervates aiming to enhance the oxidative stability of CSO. The effect of wall material composition, core-to-wall ratio and method of drying on the microencapsulation efficiency (MEE) and oxidative stability (OS) was studied The microcapsules produced using CPI-CSG complex coacervates as wall material had higher MEE at equivalent payload, lower surface oil and higher OS compared to the microcapsules produced by using CSG and CPI individually. CSO microcapsules produced by using CSG as wall material had lowest MEE (67.3%) and oxidative stability index (OSI=6.6h), whereas CPI-CSG complex coacervate microcapsules had the highest MEE (93.9%) and OSI (12.3h). The MEE and OSI of microcapsules produced by using CPI as wall materials were in between those produced by using CSG and CPI-CSG complex coacervates as wall materials. The CSO microcapsules produced by using CPI-CSG complex coacervate as shell matrix at core-to-wall ratio of 1:2 had 6 times longer storage life compared to that of unencapsulated CSO. The peroxide value of CSO microcapsule produced using CPI-CSG complex coacervate as wall material was <10meq O2/kg oil during 30 days of storage.

Desenvolvimento de pastilha potencialmente probiótica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bioequivalence of encapsulated and microencapsulated fish-oil supplementation

Omega-3 oil from fish can be stabilised against oxidation using a variety of microencapsulation technologies. Complex coacervation has been used and found to be commercially useful for fortifying foods and beverages with long-chain omega-3 containing oils. Here we report a comparative human bioavailability study of microencapsulated omega-3 fish oil and standard fish-oil soft-gel capsules. Phospholipid levels of long-chain omega-3 fatty acids increased equivalently in both subjects groups. Also, triacylglycerol levels were reduced similarly in both groups. These results indicate that omega-3 fatty acids have equivalent bioavailability when delivered as microencapsulated complex coacervates or as soft-gel capsules.