食品和饲料添加剂工业中微胶囊产品的特性研究

本文介绍了食品和饲料工业中微胶囊技术，以及微胶囊化产品微观结构的影响因素，并介绍了有关微胶囊产品稳定性、分散性、扩散性方面的基本动力模型。     

Yeast-cell-based microencapsulation of chlorogenic acid as a water-soluble antioxidant

The water-soluble antioxidant, chlorogenic acid, was successfully encapsulated in the low cost-high volume yeast cells for the first time, as characterized by FT-IR spectra and fluorescence micrograph of the yeast cells, chlorogenic acid and microcapsule.

The encapsulation efficiency (EE) of yeast cells could be enhanced significantly (P < 0.001) by the treatment of yeast cells with plasmolyser before encapsulation. Also, the release characteristics of the obtained yeast-encapsulated chlorogenic acid were evaluated, and its storage stability as a powder were investigated at 25 °C/75% relative humidity (RH), 25 °C/90% RH and 60 °C. It could be clearly demonstrated that no chemical changes had taken place during the encapsulation, and the yeast-encapsulated chlorogenic acid exhibited a good stability. This study would be helpful to promote the application of chlorogenic acid. The new yeast-cell-based encapsulation protocol may have some general interests for maintaining the stability of other water-soluble substances.     

Chemometric evaluation of binary mixtures of alginate and polysaccharide biopolymers as carriers for microencapsulation of green tea polyphenols

In this study principal component analysis and artificial neural networks were used to evaluate the potential of using binary mixtures of sodium alginate and other polysaccharide biopolymers as the carriers for microencapsulation of green tea bioactive compounds. Using binary mixtures of alginate and adjunct biopolymers increased the particle size (from 722 to 1344 µm) and textural parameters of the microbeads. Chemometric techniques revealed the combination of biopolymers and their ratio as the main factors influencing the encapsulation performance. The combination of alginate with hydroxypropyl methylcellulose and locust bean gum enabled to retain the highest (-)-epigallocatechin gallate and caffeine contents, the highest total phenols encapsulation efficiency, and their most retarded release in water, confirming these as the best delivery systems of polyphenol-type active compounds and signifying their potent food applications.     

粉末油脂的特点与在食品工业中的应用

粉末油脂是综合现代高科技技术－食品微胶囊技术加工成的水包油型（O／W）制品。由于油脂微粒为包囊壁材包埋，从而赋予了产品许多新的特性，在食品工业中广泛应用。本文介绍了粉末油脂的特性与使用方法。     

Survivability of probiotics encapsulated in alginate gel microbeads using a novel impinging aerosols method

Encapsulation of probiotic bacteria in cross-linked alginate beads is of major interest for improving the survivability in harsh acid and bile environment and also in food matrices. Alginate micro beads (10-40 μm) containing the probiotics Lactobacillus rhamnosus GG and Lactobacillus acidophilus NCFM were produced by a novel technique based on dual aerosols of alginate solution and CaCl₂ cross linking solution. Extruded macro beads (approximately 2 mm diameter) produced by the conventional method and micro beads produced by novel aerosols technique offered comparable protection to L. rhamnosus in high acid and bile environment. Chitosan coating of micro beads resulted in a significant increase in survival time of L. rhamnosus from 40 to 120 min in acid condition and the reduction in cell numbers was confined to 0.94 log over this time. Alginate macro beads are more effective than micro beads in protecting L. acidophilus against high acid and bile. Chitosan coating of micro beads resulted in similar protection to L. acidophilus in macro beads in acid and extended the survival time from 90 to at least 120 min. Viability of this organism in micro beads was 3.5 log after 120 min. The continuous processing capability and scale-up potential of the dual aerosol technique offers potential for an efficient encapsulation of probiotics in very small alginate micro beads below sensorial detection limits while still being able to confer effective protection in acid and bile environment.     

Influence of the washings on the thermal properties of polyurea-urethane microcapsules containing xylitol to provide a cooling effect

In this report, the preparation and performance of microcapsules interacting with the absorbed water to promote a cooling effect were investigated. The microcapsules containing xylitol were prepared from xylitol and diphenyl methylene diisocyanate (MDI) by an interfacial polymerization process. The microencapsulated xylitol was characterized by scanning electron microscopy (SEM) to illustrate its porous surface structure and its morphology. The influence of the drying process after washing was analyzed by differential scanning calorimetry (DSC) prior to the determination of the heat of solution. The results show the perspectives of the usage of these microcapsules as a reversible cooling agent for moisture management.     

Effect of palmitoylated alginate microencapsulation on viability of Bifidobacterium longum during freeze-drying

In the present research the viability of microencapsulated Bifidobacterium longum 15708 by extrusion and spray technique was investigated. Native (NA) and O-palmitoylated (PA) alginate were used as matrix for immobilization. Beads obtained by extrusion were characterized to assess the encapsulation yield (EY). Higher EY (67%) was found for bacteria immobilized in 3% PA. The effects of freeze drying on viability of entrapped B. longum were evaluated. Results indicated that microbeads obtained by spray were the most effective in preserving bacterial viability with a loss of viability of 2 log after 24 h as compared to extrusion beads and free cells where a loss of 2.9 and 2.75 log were respectively observed. No significant difference (P > 0.05) between NA and PA was observed. Scanning electron microscopy (SEM) analysis of beads showed globular structures and confirmed differences between the NA and PA alginates as to their appearance (porosity, fatty acid content), while the use of spray contributes to reduce the size of beads by 1/10. Present results showed that several alternatives such as beads size, alginate concentration, as well as polymer functionalization can be managed to allow probiotic viability.     

特殊用途微胶囊化粉末香精的试制研究

本研究制备的特殊用途微胶囊化粉末香精具有抗酸、碱、盐性 ,稳定性好 ,使用时具有乳化性能好 ,浑浊度高 ,速溶于水中的特性。本文根据微胶囊化粉末香精应具有的特性 ,对其原理和工艺、配方进行了研究探讨     

以大豆蛋白制备微胶囊化鱼油的研究(Ⅰ)——微胶囊化鱼油的壁材选择

研究喷雾干燥法制备高包埋量微胶囊化鱼油的壁材选择。探讨了大豆分离蛋白（ＳＰＩ）与麦芽糊精（ＭＤ）比例，ＳＰＩ热处理条件，固形物浓度，糊精ＤＥ值以及乳化剂对微胶囊化效果的影响，并经正交试验筛选出最佳壁材组成。     

聚合物包覆的亲水性碳黑纳米粒子

通过简单的相变方法,成功地在碳黑纳米粒子表面包覆上亲水性的聚乙烯醇或聚丙稀酰胺,从而赋予碳黑亲水性的表面.该方法避免了其他的聚合物包覆的方法中所涉及的复杂的聚合步骤.