Influence of different pectins on powder characteristics of microencapsulated anthocyanins and their impact on drug retention of shellac coated granulate

Blueberry extract was spray dried using different pectins and caffeine as copigment for anthocyanins in order to influence the release of anthocyanins from the shellac coated maltodextrin granulates in simulated gastric fluid. The addition of pectin did not have any influence on the structure of spray dried microcapsules as well as on the coating layer of the granulates. The initial retention of anthocyanins depended significantly on the waterbinding ability of spray dried microcapsules. The higher the waterbinding capacity of spray dried powders the lower was the anthocyanin release. Highest waterbinding capacity and lowest anthocyanin release was gained by citrus pectin with a high degree of esterification (DE) and sugar beet pectin. In general high DE pectins inhibited the release stronger than low DE pectins.     

Effect of the matrix system in the delivery and in vitro bioactivity of microencapsulated Oregano essential oil

The effect of encapsulating matrix on retention, protection and delivery of Oregano essential oil (EO) was studied. EO was encapsulated in rice starch porous spheres, inulin and gelatine/sucrose capsules by spray drying. Gelatine/sucrose matrix was also dried by freeze drying. Experimental designs were applied to test the effect of bonding agents and solids content for rice starch and drying temperature and solids content for inulin and gelatine/sucrose systems. The ratio of gelatine/sucrose was also tested. EO was identified (confocal laser scanning microscopy and FT-IR) in all tested matrices and the release profiles, antioxidant activity and antimicrobial activity of encapsulates evaluated. Results showed that the three tested materials are able to encapsulate Oregano EO. Higher diffusion coefficients were obtained for starch microcapsules (about 10⁻¹³ m²/s) followed by spray-dried gelatine/sucrose systems (about 10⁻¹⁵ m²/s) and inulin microcapsules (about 10⁻¹⁶ m²/s). Gelatine/sucrose microparticles exhibit high antioxidant and antimicrobial activity while inulin and rice starch microencapsulates ensure higher stability.     

Effects of Blueberry (Vaccinium corymbosum) Juice on Lipid Oxidation During Spray Drying of Microencapsulated Menhaden Oil

This study investigated the effect of blueberry juice on menhaden oil lipid oxidation during microencapsulation. Oil in water emulsions containing menhaden oil with 0, 5, or 10% blueberry juice were spray dried to produce control-M, 5% BJ-M, and 10% BJ-M microencapsulated powders, respectively. All microencapsulated powders had similar encapsulation efficiencies with low surface oil content. Peroxide value (meq/kg of oil) was 4.50, 4.31, and 3.38 for control-M, 5% BJ-M and 10% BJ-M, respectively. Ten percent BJ-M had lower (P < 0.05) anisidine value, and totox values than 5% BJ-M and control-M. This indicated that 10% blueberry juice reduced lipid oxidation in menhaden oil during microencapsulation to a greater extent than the other formulations.     

Effect of natural antioxidants on the lipid oxidation of microencapsulated seed oil

Lipid oxidation was effectively prevented by natural antioxidants (NA) for surface free and encapsulated oils in microencapsulated seed oil (MESO) coated with dextrin and milk protein. Three kinds of NA were extracted from rosemary, broccoli sprout, and citrus, respectively. The antioxidant effect was significantly enhanced by the use of a mixture composed of 0.05% (w/w, oil based) rosemary, 1% broccoli sprout, and 1% citrus extract. The peroxide value (POV) of the total oil in the MESO was shown to lower to about 60 meq/kg even under the accelerated storage condition at 60 ± 1 °C for 30 days. The POV of total oil from MESO was 28.1 meq/kg in the presence of antioxidants, whereas the POV of the control sample without antioxidants reached 78.8 meq/kg. The present approach can find widespread use for preventing various microencapsulated seed oils from lipid oxidation.     

Stability and release properties of curcumin encapsulated in Saccharomyces cerevisiae, β-cyclodextrin and modified starch

Curcumin, a polyphenol with pharmacological function and colouring power, was encapsulated in baker’s yeast (Saccharomyces cerevisiae) cells, β-cyclodextrin (β-CD) and modified starch (MS) by various methods. The encapsulation forms were evaluated for their efficiency in overcoming curcumin’s heat, light and oxygen sensitivity (storage stability). The release (dissolution) profile of curcumin in simulated gastric (SGF) and pancreatic fluid (SPF) was, also, obtained. All the encapsulation forms drastically increased curcumin’s solubility in SGF. A rapid dissolution of curcumin was observed for β-CD and MS microcapsules in SGF while, in yeast microcapsules, a slow and prolonged release occurred, along with low degradation rate in SPF. All the microcapsules tested protected curcumin against oxidation in environments of elevated relative humidity (%RH) and yeast microcapsules stabilized curcumin at RH above 75.5%, where oxidation was significantly increased. Yeast cells offered better protection to curcumin than did β-CD or MS against deleterious photochemical reactions and against heat degradation following isothermal (inert or oxidative) heating at 200 °C. Heating at lower temperatures (isothermal and non-isothermal) revealed that β-CD and MS can also enhance curcumin’s heat resistance.     

Characteristics of Modified β‐Cyclodextrin Bound to Cellulose Powder

Monochlorotriazinyl‐β‐cyclodextrin (MCT‐β‐CD) was covalently bonded to cellulose powder. The amount of MCT‐β‐CD bonded to cellulose could be determined by infrared spectroscopy. The coupling reaction was characterized as a physical adsorption of the MCT‐β‐CD on the cellulose powder followed by an apparently zero order chemical reaction. The reaction rate constant was found to be k = 6.43 · 10^‐4 ± 0.11 · 10^‐4 g g^‐1 s^‐1. The immobilized cyclodextrin was able to include and release d‐limonene as a model flavor compound. The maximum molar inclusion ratio was 0.85, which is the same inclusion ratio as for d‐limonene in native β‐cyclodextrin. The release rates of dlimonene included in the fixed MCT‐β‐CD were monitored at various relative humidities and 50 °C. The release kinetics could be modeled using the Avrami equation. These results demonstrate that flavors as well as other hydrophobic compounds can be included and released from MCT‐β‐CD immobilized on cellulose.     

在包装中运用微胶囊技术的研究

研究了在包装领域中运用微胶囊技术的新方法 ,以拓宽包装的功能和应用范围 ,并分析了微胶囊的基本特性及其制备方法