Zein/tannic acid complex nanoparticles‐stabilised emulsion as a novel delivery system for controlled release of curcumin

The present work was aimed to evaluate the potential of the gel‐like Pickering emulsions (50%, v/v, oil) stabilised by zein/tannic acid (TA) complex colloidal particles (ZTPE) as a new encapsulation system of lipophilic ingredients. Compared with sodium caseinate‐stabilised emulsions (SCE) and bulk oil, the better protective effects of ZTPE on the chemical stability of curcumin were observed when they suffered from UV light, and the lipid oxidation rate remarkably reduced in ZTPE. Also, the zein particle layers loaded with TA around the oil droplets can provide protection against harsh gastric environment, facilitating to slow down the release of free fatty acids (FFA) and curcumin during in vitro simulated digestion. These findings show that ZTPE have a good potential to act as an efficient encapsulating agent to protect functional ingredients from degradation and control their release during digestion, which can further improve the bioavailability of bioactive ingredients.     

用小麦醇溶蛋白/阿拉伯胶复合胶体颗粒制备植物基蛋黄酱及其性质分析

该研究采用反溶剂法制备小麦醇溶蛋白/阿拉伯胶（G/GA）复合胶体颗粒,制备不同浓度（0.5~2.0 wt%）复合胶体颗粒稳定的高内相乳液（HIPE）。复合胶体颗粒及乳液的粒度和性质分析结果显示,复合胶体颗粒的平均粒径为1.03 µm。外观上,随着复合胶体颗粒浓度的增加（1.0~2.0 wt%）,乳液的液滴的粒径逐渐减小,液滴之间的排列更紧密,形成更稳定的乳液凝胶。流变学中蛋黄酱的触变恢复率为98.62%,不同复合胶体颗粒浓度HIPE分别为83.69%（0.5 wt%）、88.52%（1.0 wt%）、86.53%（1.5 wt%）和97.17%（2.0 wt%）。摩擦系数上所有样品均呈现先减小再增大的趋势。热稳定性检测中,2.0 wt% G/GA稳定的HIPE的微观结构在加热后没有发生明显变化,液滴保持与处理前大小一致的球状,表明具有较好的热稳定性。该研究以G/GA复合胶体颗粒稳定的高内相乳液制备植物基蛋黄酱,获得与蛋黄酱性质高度相似且具有更好的热稳定性的HIPE,证明2.0 wt% G/GA稳定的HIPE具备作为植物蛋白基蛋黄酱开发应用的潜力,为替代传统动物蛋白基蛋黄酱提供了新的思路与数据支持。     

玄武岩纤维/聚苯硫醚针刺复合滤料的聚四氟乙烯乳液处理

将玄武岩纤维（BF）与聚苯硫醚（PPS）纤维以一定质量百分比（7：3）混合梳理后采用针刺加固制备玄武岩/聚苯硫醚复合过滤材料,并对制得的材料进行不同浓度的聚四氟乙烯（PTFE）乳液处理,利用扫描电镜（SEM）、电子万能材料试验机、孔径测试仪、滤料综合性能测试台,分别对滤料表观形貌、力学性能、平均孔径和过滤性能进行测试、分析。研究结果表明：乳液处理有利于改善复合滤料的过滤性能;随着乳液浓度从6%增加到14%,表层纤网之间的空隙逐渐减小;滤料的强力得到一定程度的增加;复合滤料的平均孔径从30.4μm降到23.7μm。在保证滤料强力以及较小过滤阻力的基础上,在粒径为10μm下复合材料的过滤效率从89.99%提高到98.36%,过滤性能显著提高。     

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。     

乳清分离蛋白-黄原胶复合乳化剂制备南瓜籽油O/W型乳液及其稳定性北大核心CSCD

为提高南瓜籽油(PSO)的稳定性,以及提高由单一乳清分离蛋白(WPI)作为乳化剂制备的水包油(O/W)型乳液的稳定性,制备了黄原胶(XG)与乳清分离蛋白协同稳定的南瓜籽油O/W型乳液,探究了黄原胶添加量及添加顺序对乳液性质及其稳定性的影响。结果表明:黄原胶质量浓度为2.0 mg/mL时,乳液平均粒径最小,为(10.53±0.06)μm,而ζ-电位绝对值最大,为(37.92±0.61)mV,乳液稳定性最好;黄原胶添加顺序不同,乳液稳定性有所差别,其中乳液WPI-PSO-XG(乳清分离蛋白与南瓜籽油乳化得粗乳液,再加黄原胶二次分散得到的乳液)的物理和化学稳定性最好;加速氧化实验显示,乳液的过氧化值(POV)及硫代巴比妥酸反应物(TBARS)值均低于南瓜籽油,其中乳液WPI-PSO-XG的POV和TBARS值最低,与南瓜籽油相比,分别降低了16.13 mmol/kg和17.63μmol/L,表现出良好的氧化稳定性。说明南瓜籽油与乳清分离蛋白制备成初乳液,再加入黄原胶,可使乳液稳定性提高。     

Double emulsion (W/O/W) gel stabilised by polyglycerol polyricinoleate and calcium caseinate as mangiferin carrier: insights on formulation and stability properties

Mangiferin (MGF) is a phenolic compound isolated from mango, but its poor solubility significantly limits its use. In this study, MGF was embedded into the inner aqueous phase of W₁/O/W₂ emulsions. Firstly, the dissolution method of MGF was determined. MGF remained stable in solution with pH 13 at 30 min, and its solubility reached 10 mg mL⁻¹. When the pH of MGF solutions was adjusted from pH 13 to pH 6, MGF did not immediately crystallise, providing sufficient time to construct the MGF-loaded W₁/O/W₂ emulsions. Subsequently, the MGF-loaded W₁/O/W₂ emulsions were constructed using polyglycerol polyricinoleate (PGPR) and calcium caseinate (CAS). The formation and stability of the W₁/O/W₂ emulsions were investigated. The MGF-loaded W₁/O/W₂ emulsions stabilised with 1% PGPR and 1% – 3% CAS exhibited a low viscosity, limited loading capacity, and poor stability. Conversely, the MGF-loaded W₁/O/W₂ emulsions stabilised by 3%PGPR–3%CAS exhibited optimal loading capacity (encapsulation efficiency = 95.31% and loading efficiency = 0.91%) and stability, which was attributed to the fact that high viscosity and gel state retarded the migration of inner aqueous phase. These results indicated that the W₁/O/W₂ emulsions stabilised by PGPR and CAS may be a potential alternative for encapsulating mangiferin.     

Pickering乳液法制备PPI-TA-MD微胶囊及其对南瓜籽油氧化稳定性的影响

目的:改善南瓜籽油(PSO)的氧化稳定性,促进PSO的开发利用。方法:将豌豆分离蛋白(PPI)—单宁酸(TA)稳定的Pickering乳液在麦芽糊精(MD)作为填充材料存在下,通过喷雾干燥制备南瓜籽油微胶囊,探究PPI-TA-MD包埋体系对PSO氧化稳定性的影响。结果:Pickering乳液经喷雾干燥后,可得到表面光滑的球状微胶囊粉末;随着壁材中TA浓度的增加,微胶囊显示出更小的粒径[(32.00±0.28)μm],相对较低的水分含量[(1.970±0.043)%]和较高的堆积密度[(0.725±0.014) g/cm³];不同TA浓度的PSO微胶囊FFA释放率为39.63%～69.91%,且随着TA浓度增大FFA释放速率减慢;与封装在PPI中的PSO相比,用作外壳材料的PPI-TA复合物提高了PSO的热稳定性、DPPH自由基及ABTS自由基清除能力和氧化稳定性。结论:以PPI-TA-MD为壁材的微胶囊可以改善PSO的抗氧化能力和氧化稳定性。     

有机硅改性聚氨酯/丙烯酸酯共聚乳液对棉织物的抗皱整理

为解决目前染整行业常用抗皱整理剂2D树脂的甲醛释放,以及近年来开发的多羧酸类、缩醛类、环氧树脂类等抗皱整理剂整理效果不佳、整理后织物强力降低等问题,通过溶液共聚法将自制的聚氨酯单体与丙烯酸酯类单体和乙烯基三甲氧基硅烷共聚制备了有机硅改性聚氨酯/丙烯酸酯共聚乳液,并考察了其对棉织物的抗皱整理效果。结果表明：当共聚乳液质量分数为5%,浸渍总时间为7 min,80℃预烘3 min,135℃烘焙5 min时,所整理棉织物的经纬向折皱回复角分别增大60.6°和39.1°,断裂强力增大43.3 N,断裂伸长率增大10.1%,同时还可赋予织物良好的拒水性能。     

Preparation and Characterization of Water/Oil/Water Emulsions Stabilized by Polyglycerol Polyricinoleate and Whey Protein Isolate

ABSTRACT: In this study we tried to prepare stable water-in-oil-in-water (W/O/W) emulsions using polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier and whey protein isolate (WPI) as a hydrophilic emulsifier. At first, water-in-oil (W/O) emulsions was prepared, and then 40 wt% of this W/O emulsion was homogenized with 60 wt% aqueous solution of different WPI contents (2, 4, and 6 wt% WPI) using a high-pressure homogenizer (14 and 22 MPa) to produce W/O/W emulsions. The mean size of final W/O/W droplets ranged from 3.3 to 9.9 μm in diameter depending on the concentrations of PGPR and WPI. It was shown that most of the W/O/W droplets were small (<5 μm) in size but a small population of large oil droplets (d > 20 μm) was also occasionally observed. W/O/W emulsions prepared at the homogenization pressure of 22 MPa had a larger mean droplet size than that prepared at 14 MPa, and showed a microstructure consisting of mainly approximately 6 to 7-μm droplets. When a water-soluble dye PTSA as a model ingredient was loaded in the inner water phase, all W/O/W emulsions showed a high encapsulation efficiency of the dye (>90%) in the inner water phase. Even after 2 wk of storage, >90% of the encapsulated dye still remained in the inner water phase; however, severe droplet aggregation was observed at relatively high PGPR and WPI concentrations.     

Continuous preparation of O/W nano-emulsion by the treatment of a coarse emulsion under subcritical water conditions

A coarse oil-in-water (O/W) emulsion, the oil phase of which was octanoic acid, was prepared at a very low surfactant concentration using a rotor/stator homogenizer. The emulsion was passed in a stainless steel tube immersed in an oil bath at 220 °C at a residence time of 60 s, and then mixed with the surfactant solution to produce a finely dispersed emulsion. The diameter of oil droplets in the fine emulsion was ca. 40 nm at the weight ratio of surfactant to oil of ca. 0.35 or higher.     

Protection of Lactobacillus acidophilus from the low pH of a model gastric juice by incorporation in a W/O/W emulsion

The protective effect of a W/O/W emulsion for Lactobacillus acidophilus from a model gastric juice was investigated in order to develop a method for utilizing the advantages of the probiotics. The bacteria were included in the inner-phase solution of the W/O/W emulsion, and a method for counting the viable-bacteria included in the W/O/W emulsion was developed. The relative viability of the bacteria included in the W/O/W emulsion was 49% at 2 h in the model gastric juice, whereas the viability of the bacteria directly dispersed in the juice declined to 1.3% even at 0.67 h. The relative viabilities of the encapsulated bacteria in the model gastric juice at 2 h were 0.12 and 1.10 for the emulsions having the median diameters of 11.9 and 25.4 μm, prepared with inner-phase volume ratios at 0.03 and 0.45, respectively. The relative viabilities of the bacteria in the W/O/W emulsions with the median diameters of 11 and 27 μm, prepared at the homogenization speed of 2.2×10⁴ and 9.8×10³ rpm, were 0.4 and 0.8, respectively. These results suggested that both the inner-phase volume ratio and the median diameter of oil droplet affected the relative viability of the included bacteria.     

Protection of Lactobacillus acidophilus from bile salts in a model intestinal juice by incorporation into the inner-water phase of a W/O/W emulsion

Lactic acid bacteria have been paid increasing attention as a probiotics, but their viability is affected by the various digestive processes of their host such as the acidic stomach solution and bile acids. The protection of Lactobacillus acidophilus JCM 1132 against the cytotoxic bile acids was examined by incorporating the bacteria in the inner-water phase of a W/O/W emulsion. Sodium glycodeoxycholate and sodium glycochenodeoxycholate (6 mmol/l each) significantly decreased the cell viability from 5.2×10⁶ cfu/ml to 4.0×10³ and 1.3×10² cfu/ml, respectively, when the bacteria were directly dispersed in the solutions at pH 7 for 2 h. However, their incorporation in the inner-water phase of the W/O/W emulsion improved the viabilities to 1.6×10⁶ and 2.3×10⁴ cfu/ml, respectively. This improvement was ascribed to the inclusion of the bacteria in the emulsion because the viability of the bacteria, which were dispersed with the emulsion containing no bacteria in the solution, was very low. Although sodium deoxycholate decreased the viability of the cells included in the W/O/W emulsion, the inclusion significantly improved the cell viability against primary and secondary bile acids.     

磁控溅射银/锌改性聚苯乙烯/聚偏氟乙烯复合纤维膜的制备及其性能

为制备得到兼具抗菌和紫外线防护性能的空气过滤材料,以聚苯乙烯(PS)和聚偏氟乙烯(PVDF)为原料,采用静电纺丝技术制备PS/PVDF纳米纤维膜,并在其正反两面分别磁控溅射银(Ag)和锌(Zn)纳米涂层得到PS/PVDF/Ag/Zn复合纤维膜,并对其微观形貌、元素组成、孔径分布、透气性、过滤性能、紫外线防护性能以及抗菌性能进行研究。结果表明：当溅射功率为60 W,溅射总时间为8 min时,所制得的复合纤维膜对300 nm NaCl气溶胶颗粒的过滤效率达到99.7%,压降为103 Pa,品质因子为0.056 Pa^-1;此外,该复合纤维膜的紫外线防护系数可达到702.5,对大肠杆菌和金黄色葡萄球菌的抑菌带宽度分别为3.5和6.2 mm,表现出优异的紫外线防护性能和良好的抗菌性能。     

原位聚合SiO2/PSSS纳米复合粒子的制备及其性能

以γ-（甲基丙烯酰氧）丙基三甲氧基硅烷（KH-570）对溶胶凝胶制备得到的纳米SiO2进行表面接枝改性,然后通过原位聚合制备二氧化硅/聚对苯乙烯磺酸钠（SiO2/PSSS）纳米复合粒子。研究了对苯乙烯磺酸钠（SSS）和过硫酸铵（APS）用量对SiO2/PSSS纳米复合粒子粒径的影响,探讨了SiO2/PSSS纳米复合粒子在水相中的分散稳定性。结果表明当SSS占SiO2质量分数的25%,引发剂APS占SSS质量分数的1.5%时,得到SiO2/PSSS纳米复合粒子的粒径为150nm;红外光谱（FTIR）和透射电镜（TEM）测试结果表明纳米SiO2表面成功包覆了PSSS,热失重（TGA）分析表明SiO2表面包覆聚合物的量约占其总重的27.5%,SiO2/PSSS纳米复合粒子在水相中具有良好的分散稳定性。     

磁控溅射Ag/ZnO纳米薄膜涤纶织物的制备及其性能

为探讨织物结构对表面沉积纳米复合薄膜形貌及性能的影响,采用直流射频共溅法,以不同组织结构纯涤纶织物为基材,分别以金属银(Ag)与锌(Zn)为靶材,制备Ag/ZnO纳米薄膜.对表面沉积Ag/ZnO薄膜的涤纶织物的形貌结构,沉积颜色、防紫外线性能及电磁屏蔽性能进行表征.实验结果表明:非织造布表面薄膜颗粒分布较为均匀,机织布...     

高效液相色谱-串联质谱法同时测定聚对苯二甲酸乙二醇酯/聚乙烯复合食品接触材料中16种抗氧化剂特定迁移量

目的 建立高效液相色谱-串联质谱法同时测定 16 种抗氧化剂从聚对苯二甲酸乙二醇酯/聚乙烯(polyethylene glycol terephthalate/polyethylene, PET/PE)复合食品接触材料中迁移至超纯水、3% (V/V)乙酸、10%乙醇和橄榄油这 4 种食品模拟物的特定迁移量的方法.方法 ...