辛烯基琥珀酸淀粉酯乳化白藜芦醇的工艺研究

以辛烯基琥珀酸淀粉酯为乳化剂,白藜芦醇为药物模板,利用剪切乳化结合高压均质技术制备白黎芦醇乳液,单因素实验考察了剪切乳化过程中乳化剂用量、乳化时间、乳化温度和白藜芦醇加入量对初乳液稳定性的影响,获得制备白藜芦醇初乳液的优化工艺为SSAS加入量4%,白藜芦醇加入量0.2%,乳化温度50℃、乳化时间20 min,此条件下SSAS制备的白藜芦醇初乳液的稳定性较好。在剪切乳化优化工艺条件下考察了高压均质压力和均质次数对白藜芦醇乳液粒径分布的影响,结果表明,高压均质对辛烯基琥珀酸淀粉酯制备白藜芦醇乳液的粒径分布有显著影响,均质压力在40~100 MPa、均质2次的条件下,乳液的粒径分布较好。     

高压均质对大豆蛋白乳液性质影响的研究进展

大豆蛋白作为一种高分子蛋白质,具有良好双亲性和表面活性,可通过在油水界面形成粘弹性蛋白层的方式在乳液中起到乳化作用,从而提高乳液体系的稳定性。高压均质技术是一种通过静高压和均质阀产生的综合效应从而改变蛋白质的结构和加工特性的新型非热加工技术,可以制备纳米级的大豆蛋白乳液。本文聚焦大豆蛋白乳液,阐述了高压均质制备大豆蛋白乳液的过程以及均质条件的影响,分析总结了高压均质处理对大豆蛋白乳液结构（粒径、ζ-电位、空间结构）和功能特性（流变特性、乳化性能和凝胶性能）影响的国内外研究进展及作用机理。最后,针对目前研究进展对高压均质在大豆蛋白乳液的加工应用做出展望,以期为大豆蛋白乳液的研究提供一定的帮助。     

基于双包被技术的对光稳定性姜黄素乳液制备

利用动态高压微射流技术-双包被技术联用来提高姜黄素对光稳定性,同时制得双包被姜黄素乳液。以吸光度为考察指标,分析了抗氧化剂(植酸、PG、TBHQ)、稳定剂(墨鱼汁、EDTA、石斛汁、柠檬酸)对姜黄素光稳定性的影响;制备姜黄素乳液的水相时,以包埋率为指标,考察了乳清蛋白、OSA变性淀粉、(OSA变性淀粉+乳清蛋白)试验组对包埋效果的影响,确定了合适的单包被壁材;从包埋率、离心沉降率、光稳定性、显微拍照四个方面综合评价双包被对姜黄素光稳定性作用效果,同时确定了动态高压微射流技术均质的最适压力。结果表明,加入抗氧化剂0.1%植酸、稳定剂0.1%柠檬酸溶液可显著增强姜黄素对光的稳定性,且不受介质p H影响;以乳清蛋白为壁材的包埋率较高(71.70%);双包被姜黄素乳液的最佳制备工艺:以乳清蛋白为壁材、经60 MPa动态高压微射流均质制备单包被姜黄素,再以多孔淀粉和β-环糊精作为壁材(壁材比1∶1),芯壁比10∶1,在50℃温度下经高速分散机乳化(20 000 r/min, 4 min)。双包被效果优于单包被,双包被技术在提高姜黄素对光稳定性的同时,贮藏稳定性显著提高。     

动态高压微射流对淀粉结构特性和理化性质影响的研究进展

动态高压微射流技术作为一种食品大分子的有效物理改性方法,可显著改变淀粉颗粒大小,提高溶解度、消化率,减小结晶度、糊化焓以及黏度等性质。目前的研究大多关注动态高压微射流对淀粉表观特性和理化性质的影响,而没有将淀粉结构特性与理化性质的相关性构建起来,该文主要综述近年来动态高压微射流技术对淀粉结构、理化和消化特性的影响,总结了淀粉在动态高压微射流处理过程中结构特性与理化性质之间的潜在相关性,发现淀粉的溶解度与颗粒大小、糊化温度与分子链长短有关等。动态高压微射流技术是一种优于传统淀粉改性技术的新方法,可为具有特异性结构淀粉的定向制备及应用提供新思路。最后,针对现有研究的不足,展望了动态高压微射流技术改性淀粉的研究方向,以期为淀粉产品的开发提供一定的理论依据。     

动态高压微射流处理过程对多糖结构与理化性质的影响研究进展

动态高压微射流技术作为一种新兴的食品加工处理手段,逐渐在多糖制备与改性过程中被广泛应用,其能够通过物理作用影响多糖结构,进而改变多糖的理化性质。本文主要综述动态高压微射流技术对多糖的提取和结构以及流变性、乳化性、凝胶性等理化性质的影响,以及多糖结构与理化性质之间的关系的研究进展,分析现有研究中存在的问题,并对未来研究的重点方向进行总结和展望。     

动态高压微射流制备β-乳球蛋白纳米乳液

该实验以β-乳球蛋白为原料,利用动态高压技术制备β-乳球蛋白纳米乳液。以乳液粒度及其分布、电位为评价指标,确定最佳工艺条件(蛋白浓度、均质压力、均质次数),并研究pH、温度、离子强度、防腐剂等环境因素对乳液体系稳定性的影响。结果表明:β-乳球蛋白质量浓度1.0 g/100 mL、120 MPa高压微射流均质3次为乳液制备的最适条件;乳液的粒径普遍在200 nm左右,且粒径分布较为集中,说明通过该法制备的乳液的均一性较高;该乳液对弱酸性及碱性、盐离子浓度、热及防腐剂均有较好的稳定性,表明β-乳球蛋白乳液具有较高的研究应用价值。     

酪蛋白酸钠稳定的海藻油纳米乳液制备及表征

本文研究了酪蛋白酸钠稳定的平均粒径小于100 nm的海藻油乳液(O/W)的一般性质及环境因素对其稳定性的影响。采用微射流高压均质结合溶剂(乙酸乙酯)辅助蒸发法制备了海藻油含量1%的乳液(EAE-nano),用微射流高压均质法制备海藻油含量10%的乳液(AE-nano)作为对照。将AE-nano稀释10倍后与EAE-nano对比观察,AE-nano为乳白色,而EAE-nano呈半透明状。用动态光散射技术研究了EAE-nano的一般性质;以及加入0~500 mmol/L的Na Cl、在3.0~7.0的范围调节p H值、用沸水加热处理等环境因素对乳液物理稳定性的影响。在p H为7.0时,EAE-nano的平均粒径为76.8±0.5 nm,AE-nano的平均粒径为180.9±2.1 nm;EAE-nano比AE-nano对于Na Cl、p H值的变化、加热处理等环境压力有更好物理稳定性。用微射流高压均质结合溶剂辅助蒸发法制备的酪蛋白酸钠稳定的食品级乳液,在饮料的生产和疏水性生物活性物质的包封等应用方面显示出很高的潜在应用价值。     

高压微射流对大豆分离蛋白化学性质及结构的影响

采用高压微射流技术处理大豆分离蛋白,并对其化学性质及结构变化进行了研究。结果表明,大豆分离蛋白经过高压微射流均质,在40,80,120和160 MPa下处理后,其溶解度、泡沫稳定性和持油性均得到了改善,但乳化性、持水性能变差。傅里叶变换红外光谱图显示,经高压微射流技术处理后的大豆分离蛋白二级结构发生变化。扫描电镜显示,高压微射流技术在0.1~120 MPa的压力范围内会使大豆分离蛋白颗粒破碎,且破坏程度随着压力的增加而加剧,但当压力达到160 MPa时,颗粒聚集的速度高于破碎的速度,颗粒尺寸稍微变大。高压微射流影响了大豆分离蛋白的结构,从而影响了化学性质,为其在食品工业中的应用提供了理论依据。     

均质工艺对制备鱼油微胶囊结构和理化性质的影响

本实验分别利用高压均质、空化射流和超声破碎3 种均质方式制备以大豆分离蛋白和磷脂酰胆碱包裹的鱼油纳米乳液和微胶囊,并对纳米乳液粒径、Zeta-电位、稳定性、黏度、乳化产率及微胶囊形貌、理化性质、稳定性进行比较分析,研究均质工艺对鱼油纳米乳液和微胶囊理化性质的影响。结果发现,空化射流工艺制备的纳米乳液平均粒径小,乳化产率和乳液稳定性较高,经过空化射流10 min制备的微胶囊包埋率达87.44%,溶解度较高,微胶囊颗粒表面形态饱满、致密、无裂纹和空隙,氧化稳定性和热稳定性较好。高压均质和超声破碎制得的纳米乳液平均粒径大,乳化产率和乳液稳定性较低,经过100 MPa高压均质和400 W超声破碎制得的微胶囊包埋率分别为80.36%和78.64%,溶解度相较于空化射流差,微胶囊颗粒表面分别出现微孔和较大的孔洞,氧化稳定性和热稳定性较差。傅里叶变换红外光谱分析结果表明3 种均质工艺均有较好的包埋效果。通过实验可以得出空化射流均质工艺制备的鱼油纳米乳液及微胶囊在产品性能上要优于其他两种均质工艺。本研究可为鱼油纳米乳液和微胶囊产品的均质工艺选择以及应用评价体系的构建提供理论依据。     

纳/微乳化技术在饮料中应用的研究进展

简要介绍了微乳液、纳米乳液的性能特点,对纳/微乳化技术在饮料行业的应用研究进展进行了总结,主要从香精香料的纳/微乳化、增溶营养物质、着色、制备风味饮料、纳/微乳化抗菌剂等几个方面探讨了纳/微乳技术在饮料中的应用,并对纳/微乳化体系在食品工业中的应用前景进行了展望。     

Emulsion-based delivery systems for lipophilic bioactive components

ABSTRACT:  There is a pressing need for edible delivery systems to encapsulate, protect, and release bioactive lipids within the food, medical, and pharmaceutical industries. The fact that these delivery systems must be edible puts constraints on the type of ingredients and processing operations that can be used to create them. Emulsion technology is particularly suited for the design and fabrication of delivery systems for encapsulating bioactive lipids. This review provides a brief overview of the major bioactive lipids that need to be delivered within the food industry (for example, ω-3 fatty acids, carotenoids, and phytosterols), highlighting the main challenges to their current incorporation into foods. We then provide an overview of a number of emulsion-based technologies that could be used as edible delivery systems by the food and other industries, including conventional emulsions, multiple emulsions, multilayer emulsions, solid lipid particles, and filled hydrogel particles. Each of these delivery systems could be produced from food-grade (GRAS) ingredients (for example, lipids, proteins, polysaccharides, surfactants, and minerals) using simple processing operations (for example, mixing, homogenizing, and thermal processing). For each type of delivery system, we describe its structure, preparation, advantages, limitations, and potential applications. This knowledge can be used to facilitate the selection of the most appropriate emulsion-based delivery system for specific applications.     

大豆蛋白乳液的研究进展

食品乳液作为活性物质的传递体系一直是国内外的研究热点。大豆蛋白作为一种植物高分子蛋白质,具有独特的营养价值和良好的乳化性,在改善食品感官品质和提高乳液体系稳定性上具有显著的优势。由于双亲性和高表面活性,大豆蛋白乳液得到了迅速的发展,纳米乳液、微米乳液、多重乳液、Pickering乳液、多层乳液等新型乳液以及基于乳液的固体脂质颗粒、微胶囊化和水凝胶填充颗粒,在食品、保健品、化妆品等领域有着广泛的应用前景。本研究主要综述了大豆蛋白基本结构与功能特性的关系,阐明了大豆蛋白乳液的基本性质与制备方法,并对大豆蛋白乳液的应用以及未来的发展前景进行了展望,以期为大豆蛋白乳液的加工与应用提供参考。     

DHA乳状液制备工艺优化及氧化稳定性的研究

以二十二碳六烯酸(Docose Hexaenoie Acid, DHA)微藻油微胶囊化过程中形成的乳状液为研究对象,研究乳状液制备工艺条件及氧化稳定性。利用透射光浊度法和电导率法测定乳状液的稳定性,研究预乳化时间、乳化温度、均质压力、均质级数对乳状液稳定性的影响。以乳状液稳定性和表面张力为评价指标,在单因素试验基础上采用正交试验对乳状液制备工艺进行优化,制备后进行微胶囊包埋,分析了DHA微藻油微胶囊的氧化稳定性。结果表明,乳状液制备的最佳工艺为乳化温度50℃、均质压力30 MPa、预乳化时间3 min,2级均质,在此条件下,透射光浊度法测定得到乳状液稳定性为8.75%,表面张力为20.5 mN/m。乳状液制备工艺优化后得到的DHA微胶囊氧化稳定性得到显著提高。     

Nanoemulsions: Techniques for the preparation and the recent advances in their food applications

Nanoemulsions are the transparent or translucent type of emulsion having droplet sizes ranging from 20 to 500 nm. The stability and application of nanoemulsions depend on the droplet and physicochemical characteristics. The droplet characteristics are studied through the droplet size, droplet composition, droplet concentration, zeta potential, polydispersity, and interfacial tension. The physicochemical properties are studied by their optical property, rheological property, gravitational separation, droplet aggregation, Ostwald ripening, and chemical stability. The emulsifiers and surfactants aid in the emulsification process and are selected according to the requirements of emulsification methods and expected nanoemulsion quality. The methods used for nanoemulsion preparation can be broadly classified into high-energy and low-energy methods. The high-energy methods include high-pressure valve homogenization, high-pressure microfluidic homogenization, ultrasonic homogenization, and rotor-stator homogenization. Similarly, the low energy methods are phase inversion temperature, phase inversion composition, spontaneous emulsification, membrane emulsion, and solvent displacement/solvent evaporation method. The high-energy methods are rapid in comparison to low-energy methods and can handle a large volume of liquid. The low energy methods provide better control over droplet size. Nanoemulsions have broad applications in the food industry such as in the quality enhancement and shelf-life improvement of bakery products, dairy products, meat products, fruit and vegetable products, and also in probiotics and nutraceuticals.     

A novel nanoemulsification method of stirring at the Θ-point with the tocopherol-based block co-polymer nonionic emulsifier PPG-20 Tocophereth-50

Nanoemulsions have recently become increasingly important as potential vehicles for the controlled delivery of cosmetics and for the optimized dispersion of active ingredients in particular skin layers. The preparation of conventional nanoemulsions requires mainly high‐pressure homogenization, which is unproductive and requires high energy due to its lower efficiency, limiting their practical applications. In order to solve these problems novel nanoemulsions were studied using a model system of pseudo‐ternary water/emulsifier/paraffin oil. Nanoemulsions were prepared by stirring a mixture of the tocopherol‐containing block co‐polymer emulsifier PPG‐20 Tocophereth‐50, paraffin oil, and distilled water at the Θ‐point using weight fractions of the dispersed phase (φ) of 0.31 to 0.82 and an emulsifier content of 1.0 to 9 wt.%. The emulsifying property of PPG‐20 Tocophereth‐50 in nanoemulsions was compared with that of the conventional emulsifiers Tocophereth‐43, a mixture of polysorbate 60 and sesquioleate (3/1), and phospholipids. Also the emulsifying property of PPG‐20 Tocophereth‐50 in the more hydrophilic oils caprylic/capric triglyceride and octyldodecanol was compared with that in paraffin oil. The stability and morphology of the resulting nanoemulsions were studied by visual inspection, optical microscopy, particle size analysis, and cryo‐scanning electron microscopy. In the nanoemulsion systems containing caprylic/capric triglyceride and octyldodecanol, respectively, as an oil phase PPG‐20 Tocophereth‐50 showed emulsification properties similar to those in paraffin oil. The conventional emulsifiers Tocophereth‐43, a mixture of polysorbate 60 and sesquioleate (3/1), and phospholipids did not give nanoemulsions with high‐speed stirring. The block co‐polymer nonionic emulsifier PPG‐20 Tocophereth‐50 was found to produce stable nanoemulsions of mean droplet diameters ranging from 204 to 499 nm. The emulsification method of high‐speed stirring at the Θ‐point using PPG‐20 Tocophereth‐50 was found to be very effective for the preparation of stable nanoemulsions useful for applications in skincare cosmetics, cosmeceuticals, and drugs.     

Emulsion electrospinning: Fundamentals,food applications and prospects

BackgroundIn the past decades, many natural bioactive compounds with antioxidant, immunoregulatory, antimicrobial, and anticancer activities have been successfully identified in plant and animal materials. However, due to their poor solubility, unfavorable flavor, low bioavailability and instability during food processing and storage, the development of bioactive compounds used in the food industry presents many technological challenges.Scope and approachEmulsion electrospinning is a novel and simple technique to fabricate core-shell nanofibers, and either water-in-oil (W/O) or oil-in-water (O/W) emulsions can be electrospun to directly encapsulate hydrophilic or hydrophobic compounds into core-shell fibers, respectively. This review introduces fundamentals and advantages of emulsion electrospinning as well as its food applications. The effects of different types of emulsifiers on the formation of emulsion systems and emulsion-based electrospun fibers are highlighted. Further, the existing limitations and scope for future research are discussed.Key findings and conclusionsRecent studies have found that the emulsion-based electrospun nanofibers can enhance the encapsulation efficiency, stability, and bioavailability of bioactive compounds, as well as achieve targeted delivery and controlled release, thus providing new strategies to improve their barrier performance compared to conventional electrospinning and therefore facilitating the development of emulsion-based electrospun mats in the food industry.     

高压微射流处理对大豆分离蛋白结构功能特性及其乳液性质的影响

采用高压微射流技术在不同压力条件下对大豆分离蛋白(SPI)进行处理,分析处理前后SPI结构、功能特性以及乳液性质的变化。结果表明:低压均质处理可使SPI的粒径降低,当均质压力增加至一定程度时,蛋白间的相互作用增加,颗粒粒径增加;均质压力在0～95 MPa范围内随着压力逐渐升高,SPI的溶解性得到了显著改善,而当均质压力增加到125 MPa和155 MPa时,溶解性反而降低;高压均质处理对乳化性的影响与溶解性变化趋势基本吻合;表面疏水性随着压力的增大而增大;内源荧光光谱结果表明,随着均质压力的增大,最大吸收波长红移,荧光强度降低,色氨酸残基暴露于极性环境中; SPI乳液粒径随着均质压力的增大(95 MPa除外)整体依次变小,SPI乳液在压力65 MPa处理时油脂氧化速率最快,SPI乳液在压力125、155 MPa处理时的初级氧化速率要低于未处理的乳液。     

高压均质对二十二碳六烯酸功能因子输送体系稳定性影响

以酪蛋白酸钠-葡萄糖美拉德反应产物（Millard reaction products,MRPs）作为乳化剂,在不同的均质条件下制备O/W型二十二碳六烯酸（docosahexaenoic acid,DHA）藻油乳状液,以相同条件下单独的酪蛋白酸钠作为对比,利用稳定性分析仪分析、贮藏期间的氧化程度分析和激光共聚焦显微镜观察对DHA藻油乳状液的物理稳定性、氧化稳定性和微观结构进行评价。结果显示：利用酪蛋白酸钠-葡萄糖MRPs制备的DHA藻油乳状液的物理稳定性和氧化稳定性远优于同等条件下单独的酪蛋白酸钠,说明酪蛋白酸钠经美拉德反应改性后具有优良的乳化性和抗氧化活性;同时,均质压力和次数对乳状液的稳定性和微观结构具有明显的影响。较优的工艺条件为均质压力95 MPa、均质3 次,此时酪蛋白酸钠-葡萄糖MRPs制备的DHA藻油乳状液的状态较好,Turbiscan稳定性分析仪对其扫描结果显示,乳状液只有轻微的顶部脂肪上浮和底部澄清,稳定性系数为1.55,小于其他各组;室温（25 ℃）贮藏28 d期间的总氧化值处于同期的最低水平;激光共聚焦显微镜下乳状液中油滴的粒径较小,主要分布在0.47～0.59 μm之间,且形态完整、较为均一。     

Modulation of physicochemical properties of lipid droplets using β-lactoglobulin and/or lactoferrin interfacial coatings

There is considerable interest in the development of food-grade delivery systems to encapsulate, protect and release bioactive lipids. In this study, emulsion-based delivery systems were prepared consisting of lipid droplets covered by β-lactoglobulin (BLG) and/or lactoferrin (LF) coatings. BLG and LF are globular proteins with relatively low (pI ∼ 5) and high (pI ∼ 8) isoelectric points, respectively. Mixed systems were prepared by adding LF to BLG-stabilized corn oil-in-water emulsions (BLG/LF-coated droplets) or by adding BLG to LF-stabilized corn oil-in-water emulsions (LF/BLG-coated droplets) at pH 7, where there is an electrostatic attraction between the proteins. The influence of pH (3–7), ionic strength (0–60 mM CaCl₂ or 0–200 mM NaCl, pH 7), and thermal treatment (21–90 °C, pH 7, 20 min) on the physical stability of the resulting emulsions was examined. Emulsions with good stability to pH, salt, and thermal processing could be created using mixed interfacial coatings. In addition, we found that the lipids in these emulsions could still be digested using an in vitro digestion model to simulate small intestine conditions. This work may lead to the formation of emulsion-based delivery systems with improved physicochemical and functional performance.