天然皂苷自组装及其对食品胶体功能特性影响的研究进展

皂苷（Saponin）作为广泛存在于天然植物界中的一大类糖苷近年来受到广泛关注。在分子结构上,天然皂苷是以三萜或甾体苷元的疏水基为支架并附着亲水性糖链所构成,从而表现出高界面活性。天然皂苷分子结构的多样性不仅使其具有生物活性和独特的物理化性质,促进其在食品、化妆品以及其他领域中的广泛应用。本研究结合近年来对天然皂苷结构特性、自组装和界面特性的研究,试图探究皂苷结构如何影响其在水相、气-水界面、油-水界面和固-液界面的组装行为,以及其对食品胶体功能特性的影响。自组装和界面结构可能因植物来源和分子结构而不同：具有三萜结构的皂苷最有助于形成粘弹性界面膜,产生稳定的食品胶体;而甾烷类皂苷更倾向于具有特殊的生理活性。其中天然皂皮皂苷表现最为优异,已被证实可形成稳定的胶束、纳米乳液、乳液凝胶和泡沫等用于生物活性物质的输送,目前已被包括中国、美国和欧盟等多数国家批准用于食品。     

环境因素对大豆球蛋白-大豆皂苷复合乳液稳定性的影响

大豆球蛋白是一种优质植物蛋白,而大豆皂苷则是一种天然两亲性小分子活性物质,二者均可单独作为界面稳定剂制备水包油乳液,但在部分环境因素的影响下乳液的稳定性较差.将大豆球蛋白与大豆皂苷混合后作为乳化剂制备复合乳液,研究了典型环境因素(酸、温度、冻融)对大豆球蛋白-大豆皂苷复合乳液稳定性的影响.采用多重光散射技术对热(90、...     

小麦醇溶蛋白与茶皂苷的相互作用及其对甘油基泡沫性质的影响

本研究通过调控大分子-小分子相互作用构建界面主导的食品泡沫体系,首次利用食品级甘油作为绿色共溶剂溶解疏水性小麦醇溶蛋白和两亲性小分子茶皂苷,进一步研究和评估了蛋白-茶皂苷复合体系的相互作用及其泡沫形成和稳定能力。内源荧光光谱分析荧光猝灭参数为1.345×109 M-1 S-1,其远远小于最大动态猝灭常量(2×1010 M-1 S-1),说明由茶皂苷介导的动态猝灭可促使蛋白与茶皂苷通过非特异性疏水相互作用形成复合体系。通过界面动态吸附结果可知,与单纯的小麦醇溶蛋白或茶皂苷相比,蛋白-茶皂苷复合体系在适宜的茶皂苷浓度(0.5%～0.75%)下可通过两者在气-甘油界面的相互作用增强界面活性及覆盖面积。激光共聚焦图片显示在上述茶皂苷浓度下小麦醇溶蛋白富集在气泡表面,可形成尺度更小的泡沫,最终提高小麦醇溶蛋白-茶皂苷复合体系的起泡能力和泡沫稳定性。     

蛋白质-多糖在乳液油-水界面相互作用研究进展

蛋白质和多糖是具有一定乳化性能的天然生物聚合物,两者可以在乳液油-水界面相互作用并形成具有弹性的界面膜。与化学合成的乳化剂相比,这种天然乳化剂安全性更高,在医药、化妆品和食品等领域更具应用前景,但其乳化特性无法从乳液的宏观状态观察得出,通过分析乳液油-水界面的特性则能够从机理上对乳化剂的乳化效果进行说明。主要介绍了乳液稳定的机理以及探究乳液界面性质的方法,阐述了蛋白质和多糖的复合方式及两者之间的相互作用,并对蛋白质-多糖复合物的研究趋势作出展望。     

食品体系中泡沫的稳定性及其影响因素研究进展

泡沫是气体分散在液体或半固体中的分散体系,对稀奶油、冰淇淋、啤酒等界面主导食品的口感、质地和外观等品质的形成发挥着重要作用。研究人员在探索发泡技术与不同界面主导食品创新结合的同时,也期望厘清泡沫在食品体系中形成与稳定的机制。然而泡沫属于高度热力学不稳定体系,极易发生排液、聚结和歧化等现象,如何在复杂的食品体系中得到最佳的泡沫稳定性,需要兼顾多种因素的影响。因此本文从探究泡沫失稳机理出发,系统综述不同物质的泡沫特性及不同食品中泡沫的稳定机制,并重点从气-液界面角度阐释了表面活性剂及加工助剂、固体颗粒、加工条件及技术等因素对泡沫稳定性的影响。旨在为泡沫在界面主导食品中的开发与稳态化提供理论指导。     

基于改性果胶的纳米乳液包埋生物活性物质研究进展

果胶是从苹果渣、柑橘皮和甜菜粕等原料中提取的一种结构复杂的阴离子多糖,具有特殊的表面和界面特性,是构建纳米乳液的理想材料。然而,天然果胶的亲水性较强,疏水性不足,不易吸附到两相界面并发挥作用,限制了其在食品等领域的应用。对天然果胶进行甲酯化改性,或者将果胶与小分子表面活性剂(如吐温、司盘等)或大分子表面活性剂(如蛋白质等)联合使用,能够有效克服天然果胶在稳定纳米乳液时的缺陷,提高纳米乳液的稳定性和生物活性物质的包埋效果。本文综述基于改性果胶的纳米乳液制备方法、表征手段,以及不同形式的果胶基乳化剂的界面及乳化性质,旨在为果胶基纳米乳液体系的构建及其在生物活性物质包埋中的应用提供理论依据。     

花生蛋白稳定乳液研究进展及应用现状

花生是我国第一大油料作物,制油后的花生饼粕中蛋白含量可达45%～55%。花生蛋白具有较高的消化性,有效利用率高达98%,是极具营养价值的天然蛋白质资源。花生蛋白主要由花生球蛋白和伴球蛋白组成,在乳液制备过程中可以在油-水界面上形成黏弹性膜抵抗机械压力,并提供静电及位阻稳定,有着构建植物蛋白稳定乳液的良好潜力。为进一步提高花生蛋白基乳液稳定性,常采取将花生蛋白与多糖等天然大分子复合使用,或通过超声、高压均质等方式制备乳液。同时,花生蛋白也被应用于肉类制品、烘焙产品、生物膜等产品的制备中。该文详细综述花生蛋白乳化机制与单一/复合花生蛋白基质稳定乳液的研究进展及应用现状,阐述花生蛋白理化和结构特性对其乳液稳定性的影响,以期为后续有关花生蛋白的研究提供参考。     

纤维素稳定Pickering乳液的研究进展及在食品领域的应用

纤维素作为一种可再生资源,具有来源广泛、绿色环保、可生物降解性、生物相容性等优点。研究发现,由固体颗粒作为稳定剂制备的乳液较传统表面活性剂稳定的乳液具有更高的稳定性,而纤维素凭借其生物相容性、来源广、绿色环保等优点,成为一种良好的Pickering乳液稳定剂,同时纤维素作为一种天然的可食用膳食纤维,在食品领域中具有广阔的应用前景。本文综述不同种类纤维素稳定Pickering乳液的特点,介绍不同处理方式赋予纳米纤维素稳定Pickering乳液不同的性能,并对纳米纤维素基乳液在制备食品级高分子材料、制备新型低热量食品、输送生物活性物质及辅助消化等食品领域的应用进行叙述,为拓宽纤维素基Pickering乳液应用提供参考。     

盐离子对大豆乳清混合蛋白乳液的稳定性及界面特性的影响

采用大豆分离蛋白-乳清分离蛋白（SPI-WPI）作为乳化剂形成水相,加入大豆油作为油相,制备O/W乳液,通过粒径、Zeta电位、乳液稳定性系数、激光共聚焦显微镜、界面蛋白吸附量、界面压力及界面膨胀流变等指标探究不同盐离子浓度（0~0.5 mol/L NaCl）对混合蛋白界面特性及乳液稳定性的影响。结果表明:盐离子会使混合蛋白乳液表面电位增加,且随着NaCl浓度的增加,乳液的体积平均粒径（D₄₃）升高,乳液稳定系数降低,乳液稳定性降低。并且,盐离子浓度为0.05 mol/L时,乳液最为稳定。此外,盐离子会使SPI-WPI在油-水界面的相互作用较弱,从而导致SPI-WPI溶液的界面压力值增大,在油-水界面的总模量（E）、弹性模量（E_d）、粘性模量（E_v）等降低,进而影响乳液的稳定性。这为食品产业生产较稳定的双蛋白乳液提供了理论依据。     

多糖颗粒制备Pickering乳液稳定机制研究进展

多糖颗粒为潜在的Pickering乳液稳定剂,通过产生分子间静电相互作用和空间位阻,防止乳液液滴聚集。基于此,该文综述多糖颗粒的制备方法及多糖稳定Pickering乳液机制,并总结多糖相对分子质量、亲油性基团等特性对其乳化性的影响,为多糖颗粒稳定的Pickering乳液在食品中的应用开发提供参考。     

Protein–flavour interactions in relation to development of novel protein foods

Proteins are known to interact with relatively small molecules such as flavour compounds and saponins, and may thus influence the taste perception of food. In this study, the interactions of flavour volatiles with pea proteins, and the effects of heat on these interactions were investigated. The presence of saponins, which are non-volatile flavour compounds, was also explored. Saponins are known to contribute to the bitterness in pea and were found to interact with proteins. Pea proteins, legumin (11S) and vicilin (7S), were used for interaction studies with aldehydes and ketones using static headspace-gas chromatography (SH–GC). The binding of various flavour compounds as a function of concentration was studied at pH 7.6 and pH 3.8. Vicilin binds both aldehydes and ketones at pH 7.6 and pH 3.8. Legumin only showed binding to aldehydes at pH 7.6 and no binding to aldehydes or ketones at pH 3.8. The effect of heat on vicilin-flavour interactions was studied at pH 7.6. Heating of vicilin seemed to lead to a decrease in the binding of aldehydes and ketones to the protein. In addition, the presence of saponins in hulled pea flour was identified by high performance liquid chromatography and mass spectrometry (HPLC–MS) and three groups of saponins, A, B and DDMP saponins were found to be present, with group B saponins dominating.     

植物多酚-蛋白质复合物生物活性及应用研究进展

蛋白质与植物多酚是食品体系中的重要组成成分,其相互作用被广泛研究,这种相互作用对于合理设计功能性食品和提高多酚、蛋白质的生物利用率具有重要意义.本文主要从植物多酚与蛋白质的关系出发,阐述影响多酚与蛋白质相互作用的因素;同时重点总结近几年多酚-蛋白质复合物的抗氧化性、消化性、致敏性和抑菌性等生物活性的研究进展及其在食品医...     

蛋白质微胶的制备、形成机制及应用

蛋白质微胶具有优异的尺寸效应、生物兼容性和疏水分子荷载能力,可望成为新一代功能性食品配料。本文对蛋白微胶的制备技术,形成机制及调控进行了综述,重点讨论蛋白质聚集行为控制与蛋白质微胶形成的关系;提出营养微胶的概念;对蛋白质微胶形成时蛋白与植物多酚的相互作用进行了分析;阐述了蛋白质微胶的界面吸附行为和凝胶特性及其在真实食品体系的应用情况。     

Relevance of the air–water interfacial and foaming properties of (modified) wheat proteins for food systems

A shift from animal protein- to plant protein-based foods is crucial in transitioning toward a more sustainable global food system. Among food products typically stabilized by animal proteins, food foams represent a major category. Wheat proteins are ubiquitous and structurally diverse, which offers opportunities for exploiting them for food foam and air–water interface stabilization. Notably, they are often classified into those that are soluble in aqueous systems (albumins and globulins) and those that are not (gliadins and glutenins). However, gliadins are at least to an extent water extractable and thus surface active. We here provide a comprehensive overview of studies investigating the air–water interfacial and foaming properties of the different wheat protein fractions. Characteristics in model systems are related to the functional role that wheat proteins play in gas cell stabilization in existing wheat-based foods (bread dough, cake batter, and beer foam). Still, to further extend the applicability of wheat proteins, and particularly the poorly soluble glutenins, to other food foams, their modification is required. Different physical, (bio)chemical, and other modification strategies that have been utilized to alter the solubility and therefore the air–water interfacial and foaming properties of the gluten protein fraction are critically reviewed. Such approaches may open up new opportunities for the application of (modified) gluten proteins in other food products, such as plant-based meringues, whippable drinks, or ice cream. In each section, important knowledge gaps are highlighted and perspectives for research efforts that could lead to the rational design of wheat protein systems with enhanced functionality and overall an increased applicability in food industry are proposed.     

Sheep foraging behavior in response to interactions among alkaloids,tannins and saponins

BACKGROUND: A mixture of plant species adds biochemical diversity to pastures that may enhance productivity while decreasing reliance on herbicides and insecticides. All plants contain secondary metabolites (PSMs) that interact in plant communities in a variety of ways. Our objective was to determine if PSM diversity enhanced food intake when sheep were allowed to select from foods that varied in concentrations of tannins, saponins, and alkaloids. We hypothesized that intake of foods containing alkaloids would increase when sheep were offered supplemental foods with tannins and saponins. The alkaloid gramine is proteinaceous in nature, tannins bind to proteins in the gut, which enhances excretion of proteins, so we hypothesized tannins would bind to gramine and enhance its excretion from the body. The alkaloid ergotamine is steroidal, saponins have a high affinity for binding to lipid and steroidal compounds in the gut and then being excreted, so we hypothesized saponins would bind to ergotamine and enhance its excretion from the body. RESULTS: We found that sheep fed either gramine or ergotamine in combination with tannin‐ or saponin‐containing foods had higher intakes of food than sheep offered only foods with gramine or ergotamine. CONCLUSION: These findings are consistent with the hypothesis that animals can neutralize the negative effects of alkaloids by ingesting tannins and saponins. Our results show that PSMs can complement one another to increase a herbivore's intake of unpalatable plant species, with the potential to maintain healthy animals and bio‐diverse landscapes. Copyright © 2008 Society of Chemical Industry     

多酚与蛋白质相互作用及其对蛋白质影响

多酚因对人类健康有潜在的积极作用而广泛应用在食品体系中。多酚可与食品体系中的蛋白质通过共价或非共价相互作用形成复合物,进而影响蛋白质的结构和性质。作者综述了多酚与蛋白质相互作用机制,及相互作用对蛋白质结构、功能特性、酶活性、氧化性和消化率的影响,并总结了二者相互作用机制的常见分析方法。最后,对多酚与蛋白质相互作用的未来研究方向进行了展望。     

花色苷基于分子辅色机制的稳态化制备与应用技术研究进展

源于天然植物的花色苷是集着色、增香和保健作用于一体的新一代功能性食品配料,但在食品加工过程中易受多种外界因素的影响而发生水解或去糖基开环反应,导致产品褪色、风味品质劣变及生物活性丧失。而研究发现在自然生化条件下,植物花色苷通过其内部的多种化学成分(多酚、生物碱、核苷酸和金属离子等)的分子辅色作用而维持稳定性,从而实现花色苷食品的色泽、风味和营养的稳态化。目前通过模拟植物花色苷的分子辅色作用也成为研究功能性色素的重要内容之一。本文在分析花色苷分子辅色作用机制基础上,重点综述了近年来的天然植物花色苷基于分子辅色技术的稳态化制备工艺及相关应用技术取得的最新进展,为植物花色苷食品的稳态化加工技术研究提供依据和参考。