米糠蛋白O/W及W/O/W乳液制备及界面稳定性

为对比不同米糠蛋白质量浓度下O/W及W/O/W乳液的稳定性,以米糠蛋白作为基料,采用双乳化法制备O/W及W/O/W乳液,考察不同米糠蛋白质量浓度下乳液的微观形态和稳定性并探究其界面稳定机理。结果表明：W/O/W乳液的贮存稳定性显著优于O/W乳液;与相同蛋白含量的O/W乳液相比,W/O/W乳液的黏度显著提高;当米糠蛋白质量浓度为0.4 g/100 mL时,W/O/W乳液的稳定性较O/W乳液提高了1 倍以上;乳液内部包裹更多的W/O液滴,W/O/W乳液的粒径较大;而此时静电斥力也较大,起到稳定乳液的目的。同时,米糠蛋白质量浓度不小于0.4 g/100 mL时,O/W及W/O/W乳液中蛋白质的吸附率较高,达到78%以上。本研究为天然米糠蛋白质在食品级乳液中的开发提供参考,为粮食副产物的综合利用提供了新思路。     

胭脂虫红W/O/W乳液工艺

采用双乳化法制备胭脂虫红W/O/W复合乳液,以纯胭脂虫红酸水溶液作为内水相,大豆油为油相,司盘80、磷脂为亲油性乳化剂,将内水相、油相、亲油性乳化剂混合,在高剪切分散乳化机上以10 000 r/min的转速搅拌10 min,得到初乳。阿拉伯胶溶于水作为外水相,与初乳混合后用均质机均质后得到胭脂虫红W/O/W复合乳液。结果表明,采用双乳化法制备胭脂虫红W/O/W复合乳液,不仅能提高胭脂虫红在酸性条件下的稳定性,还能解决胭脂虫红在食品中形成色斑、不易涂抹问题,并能扩大胭脂虫红在食品领域的使用范围。     

酪蛋白酸钠-明胶制备S/O/W乳状液的稳定性

碳酸钙是一种常用的强化钙,然而,其悬浮稳定性差,易产生沉淀,严重限制了碳酸钙在食品加工中的应用.以固/油/水(S/O/W)乳状液形式负载碳酸钙,构建具有特定结构分布的钙-脂质微球,有望改善其溶解性和稳定性.本文以食品级碳酸钙为S相,大豆油为O相,酪蛋白酸钠-明胶为W相,构建S/O/W钙-脂质微球,研究不同质量分数明胶和...     

盐对W/O/W双重果蔬浆乳液结构及稳定性的影响

目前双重乳液技术已应用于许多食品。食物中的一些天然成分如蛋白质等具有天然乳化剂的作用,不添加乳化剂形成的乳液结构食品有更高的食用级别。本次研究探索双重乳液(W/O/W)在天然食品原料中即不添加二级乳化剂的情况下的形成及盐对W/O/W双重果蔬浆乳液结构及稳定性的影响。结果表明:不添加第二级乳化剂及内外水相分别含KCl及NaCl时,O/W乳液、W/O/W乳液能够在一些果蔬浆中形成,形成的双重乳液W/O/W在草莓和柠檬果浆中更稳定。在草莓果浆W1/O/W2中,分散相W1/O液滴的粒径大小随加入果浆体积比例的减少而增大。KCl或NaCl的加入对于某些食品中形成优质双重乳状结构非常关键。此外,均质速度及时间同样影响果蔬浆乳液的结构和稳定性。     

食品级皮克林乳液制备及应用研究进展

食品级皮克林乳液是依靠多糖、蛋白质等可食性固体颗粒对油水界面稳定制备的乳液。与传统乳液相比,食品级皮克林乳液具有抗聚结,稳定性好和制备简易等特点,在食品加工应用方面存在潜力。本文依据皮克林乳液的稳定机理介绍影响其稳定性的因素;依据食品级皮克林颗粒的种类综述皮克林乳液的制备方法,总结其在食品中的应用,并探讨其发展方向。     

番茄红素纳米乳液体系的稳定性能研究

针对以食品级生物大分子辛烯基琥珀酸酯化淀粉（OSA变性淀粉）为乳化剂构建的负载番茄红素纳米乳液体系,采用Turbiscan AGS稳定性分析仪监测24 h内纳米乳液的稳定性变化趋势,探索体系失稳的主要原因;对负载番茄红素纳米乳液在不同储存和应用条件下的稳定性能进行系统研究。研究结果表明：奥氏熟化可能是导致番茄红素纳米乳液失稳的主要原因。不同储存条件对体系粒径和番茄红素保留率的研究结果表明：储存条件对体系稳定性影响显著,其中对乳液粒径增长的影响程度依次为温度＞光照＞氧气,对番茄红素保留率的影响依次为氧气＞温度＞光照。纳米乳液在4 ℃避光充氮气条件下储存28 d,乳液粒径仅从138 nm增到157 nm,番茄红素的保留率为41%,体现了良好的稳定性。对番茄红素纳米乳液在不同pH、离子浓度和蔗糖浓度的模拟食品体系中的稳定性研究表明,乳液的耐酸性较强,盐离子和蔗糖分子不会对纳米乳液的稳定性造成太大的影响。     

基于熊果酸的W/O/W型Pickering乳液制备方法

目的:提高熊果酸的应用范围和生物利用率。方法:以熊果酸为乳化剂,果胶为外水相,采用两步法制备W/O/W型Pickering乳液。通过单因素试验优化W/O乳液制备条件,研究果胶质量浓度对W/O/W型Pickering乳液理化性质、微观结构、流变学特性及长期稳定性的影响。结果:W/O乳液的最佳制备工艺为熊果酸质量浓度4 g/100 mL、水油质量比2∶3、均质转速9 000 r/min、均质时间5 min;以果胶为外水相制备的双层乳液粒径均在30～40μm,果胶质量浓度的增加使乳液的zeta电位绝对值、流变性能以及4℃贮藏稳定性有着显著性的提高。结论:果胶质量浓度为0.3,0.4,0.5 g/100 mL时能够制备稳定的Pickering双层乳液。     

水/水乳液的形成、稳定及功能特性研究进展

水/水乳液是一种新型胶体分散体系，目前已成为胶体与界面科学领域的研究热点。本文综述水/水乳液的形成机制、影响因素和特性，归纳总结典型天然高分子的水/水乳液体系；介绍利用颗粒、嵌段聚合物、聚电解质等3种物质稳定水/水乳液的方法，其中，重点介绍颗粒稳定水/水乳液的机理和影响因素，以及水/水乳液在活性物质荷载和淀粉消化中的应用。指出水/水乳液的未来发展方向，特别是应开发更多的食品级水/水乳液体系，以拓展在食品中的应用范围。     

蛋白种类对大豆皂苷-蛋白W/O/W型乳液稳定性的影响

将大豆皂苷添加至内水相（W1）,大豆蛋白添加至外水相（W2）,以玉米油为油相（O）,两步乳化法制备W/O/W型多重乳液。探究乳液的整体稳定性、粒径特性、电位特性、微观结构、流变学特性、界面张力以及长期稳定性的变化情况。结果表明：随着时间的延长,乳液的稳定性动力指数值呈上升趋势,粒径集中在6 μm附近,大豆分离蛋白乳液的电位绝对值最大（－30.2 mV）,该体系表现出假塑性的剪切稀化行为,大豆分离蛋白乳液的黏度值最大（0.029 Pa?s）;15 d后,所有蛋白乳液都出现了一定的分层现象,大豆分离蛋白乳液的稳定性动力指数最小（21.51）。在1%蛋白质量分数下,大豆分离蛋白制备的W/O/W型乳液稳定性优于大豆11S和7S蛋白。     

基于三种多糖与酪蛋白复配制备W/O/W型乳液及其包封红景天苷效果的研究

为提高红景天苷稳定性及口服吸收效果,本研究以红景天苷为内水相,含聚甘油蓖麻醇酯的菜籽油为油相,分别采用葡聚糖、壳聚糖和大豆多糖混合酪蛋白作为外水相,制备W/O/W型多重乳液。研究了不同浓度的三种多糖对多重乳液的微观结构、粒径、电位、贮藏稳定性、乳化性、包埋率、载药量和体外消化过程的影响。结果显示,相比于酪蛋白对照组、壳聚糖-酪蛋白组和大豆多糖-酪蛋白组,葡聚糖-酪蛋白W/O/W型多重乳液稳定性最好。高浓度的葡聚糖能够明显提升葡聚糖-酪蛋白多重乳液的贮藏稳定性,当葡聚糖添加量为1.2%时,多重乳液平均粒径最小,可达623.03±5.21 nm（P<0.05）;电位绝对值最高（P<0.05）,平均电位为?37.3±0.46 mV;对酪蛋白乳化性质提升最大（P<0.05）;对红景天苷的包埋率最高（P<0.05）,可达92.8%,载药量为162.89±4.21 μg/g。模拟消化研究发现葡聚糖-酪蛋白多重乳液不仅能有效地保护红景天苷,还能够靶向地在模拟肠道内传递和释放,葡聚糖添加量为1.2%的葡聚糖-酪蛋白负载体系的稳定性和控释效果最佳。该研究结果可为红景天苷在食品和医药中的应用提供理论支撑。     

Review on the Stability Mechanism and Application of Water‐in‐Oil Emulsions Encapsulating Various Additives

Water‐in‐oil (W/O) emulsions can be used to encapsulate and control the release of bioactive compounds for nutrition fortification in fat‐based food products. However, long‐term stabilization of W/O emulsions remains a challenging task in food science and thereby limits their potential application in the food industry. To develop high‐quality emulsion‐based food products, it is essential to better understand the factors that affect the emulsions’ stability. In real food system, the stability situation of W/O emulsions is more complicated by the fact that various additives are contained in the products, such as NaCl, sugar, and other large molecular additives. The potential stability issues of W/O emulsions caused by these encapsulated additives are a current concern, and special attention should be given to the relevant theoretical knowledge. This article presents several commonly used methods for the preparation of W/O emulsions, and the roles of different additives (water‐ and oil‐soluble types) in stabilizing W/O emulsions are mainly discussed and illustrated to gain new insights into the stability mechanism of emulsion systems. In addition, the review provides a comprehensive and state‐of‐art overview of the potential applications of W/O emulsions in food systems, for example, as fat replacers, controlled‐release platforms of nutrients, and delivery carrier systems of water‐soluble bioactive compounds. The information may be useful for optimizing the formulation of W/O emulsions for utilization in commercial functional food products.     

Double Emulsions Relevant to Food Systems: Preparation,Stability, and Applications

This review describes advances in the preparation of food‐relevant double emulsions (DEs) of the water‐in‐oil‐in‐water (W/O/W) and oil‐in‐water‐in‐oil (O/W/O) types with emphasis on research published within the last decade. The information is assembled and critically evaluated according to the following aspects: the food application area, the range of encapsulated components and emulsion composition, the emulsification preparation methods, the balancing of the osmotic pressure, the stabilization by increased viscosity or gelation, the role of protein–polysaccharide interactions, and the techniques used to estimate DE yield and emulsification efficiency. Particular focus is directed toward the control of encapsulation and release behavior, including strategies that have been employed to improve the retention ability of the inner phase droplets by modifying the outer oil–water interface through mixed ingredient interactions, Pickering stabilization by particles, and biopolymer gelation. We also briefly consider the incorporation of DEs into dried microcapsules and the stability of W/O/W emulsions during eating and digestion. It would appear that 2 outstanding issues are currently preventing full realization of the potential of DEs in food applications: (i) the lack of availability of large‐scale production equipment to ensure efficient nondestructive 2nd‐stage emulsification, and (ii) the limited range of food‐grade ingredients available to successfully replace polyglycerol polyricinoleate as the primary emulsifier in W/O/W formulations.     

A very stable W/O/W multiple emulsion

Synopsis
The comparison of the results of microscopic, conductimetric and rheologic analyses carried out on the same triple W/O/W emulsion, immediately following its manufacture and 10 years later, indicates the remarkable stability of such system. This stability illustrates the great potential of this formula in the protection of unstable ingredients, with regard to external stress, when encapsulated with a high yield.
Résumé
La comparison des résultats des analyses microscopiques effectuées sur une même fomule d'émulsion multiple H/L/H, juste après sa fabrication et après 10 ans de conservation, ont permis de mettre en évidence la remarquable stabilité de ce système. Cette stabilité démontre les grandes possibilités de cette formule dans la protection, vis à vis des milieux extérieurs, des substances fragiles incorporés avec un haut rendement d'encapsulation.     

Release rate profiles of magnesium from multiple W/O/W emulsions

Water-in-oil-in-water (W/O/W) emulsions were formulated based on rapeseed oil, olive oil, olein and miglyol. Polyglycerol polyricinoleate and sodium caseinate were used as lipophilic and hydrophilic emulsifiers, respectively. Magnesium was encapsulated in the inner aqueous droplets. Emulsion stability was assayed through particle sizing and magnesium release at two storage temperatures (4 and 25 °C) over 1 month. Irrespective of the oil nature, both the primary W/O and W/O/W emulsions were quite stable regarding the size parameters, with 10-μm fat globules and 1-μm internal water droplets. Magnesium leakage from W/O/W emulsions was influenced by the oil type used in the formulation: the higher leakage values were obtained for the oils characterized by the lower viscosity and the higher proportion of saturated fatty acids. Magnesium release was not due to droplet–globule coalescence but rather to diffusion and/or permeation mechanisms with a characteristic rate that varied over time. In addition, W/O/W emulsions were resistant to various thermal treatments that mimicked that used in pasteurization processes. Finally, when W/O/W emulsions were placed in the presence of pancreatic lipase, the emulsion triglycerides were hydrolysed by the enzyme. These results indicated a possible use of W/O/W emulsions loaded with magnesium ions in food applications.     

Preparation of Monodisperse Food-Grade Oleuropein-Loaded W/O/W Emulsions Using Microchannel Emulsification and Evaluation of Their Storage Stability

W/O/W emulsion is an emerging system in developing new functional and low-calorie food products. The aim of this study is to produce food-grade monodisperse water-in-oil-in-water (W/O/W) emulsions loaded with a hydrophilic bioactive oleuropein. W/O/W emulsions were prepared via high-pressure homogenization and subsequent microchannel (MC) emulsification. The internal aqueous phase was a 5-mM sodium phosphate buffer containing d(+)-glucose (5 wt.%) and oleuropein (0.1–0.7 wt.%). The oil phase consisted of soybean oil and tetraglycerin monolaurate condensed ricinoleic acid esters (TGCR; 3–8 wt.%). The external aqueous phase was a 5-mM sodium phosphate buffer containing d(+)-glucose (5 wt.%) and decaglycerol monolaurate (1 wt.%). Oleuropein-loaded submicron W/O emulsions with average droplet diameters as small as 0.15 μm and monomodal droplet size distributions were prepared by high-pressure homogenization when applying high TGCR concentrations of 5–8 wt.% and low oleuropein concentrations of 0.1–0.3 wt.%. Monodisperse oleuropein-loaded W/O/W emulsions with average W/O droplet diameters of around 27 μm and coefficients of variation of below 5 % were successfully prepared when using a silicon MC array plate with wide channels of 5-μm depth and 18-μm width. The monodisperse W/O/W emulsions prepared at high TGCR concentrations and low oleuropein concentrations were the most stable during 40 days of storage. The adsorption behavior of oleuropein at the internal aqueous–oil interface was relevant to W/O/W emulsions microstructure and stability. The results are believed to provide useful information for successfully preparing stable monodisperse W/O/W emulsions loaded with hydrophilic functional compounds. The surface activity of the loaded material seems to be a key parameter in optimizing the formulation of W/O/W food emulsion.     

O/W emulsion and W/O/W multiple emulsion: physical characterization and skin pharmacokinetic comparison in the delivery process of caffeine

The aim of this study was to compare the characteristics of an O/W emulsion and a W/O/W emulsion, formulated with similar ingredients. The physical properties of these two types of vehicles were characterized first. Using three types of in vitro models, human skin biopsies, nitrate acetate cellulose membranes and human reconstituted epidermis, the delivery potential of each vehicle for one hydrophilic drug, caffeine, was compared. The assessment of physical parameters, such as particle size, conductivity and rheological behavior enabled the nature of the test emulsions to be clearly identified. Clear differences were observed in the ability of each type of emulsion to deliver caffeine. Whatever the nature of the membrane used for the pharmacokinetic study, the absorption of caffeine was roughly two-fold lower (2.6 for human skin) when the W/O/W multiple emulsion was used as the vehicle. The concomitant determination of physical and kinetic properties of these two test emulsions allowed the W/O/W multiple emulsion and a simple O/W emulsion to be clearly differentiated.     

食品级Pickering乳液的研究进展

Pickering乳液是指由纳米/微米级粒子稳定的乳液。近年来,Pickering乳液因其独特的稳定性,以及在食品、药品中的包埋、载运和质地改良等方面的潜在应用,逐渐成为食品研究领域的热点。本文结合食品级Pickering粒子的相关性质解释了其稳定机制,包括三相接触角理论、吸附理论和空间屏障理论等,并分析了环境因素如温度、pH值和盐浓度等对乳液制备及稳定性的影响;综述了近年来开发的一系列食品级Pickering粒子的制备方式、性质及其实际应用情况,以期推动Pickering乳液在食品领域的研发及工业应用。