Water activity of multicomponent mixture of solutes and non-solutes

An equation has been derived to calculate the water activity (A_w) of multicomponent mixtures of solutes and non‐solutes. The equation is based on a previous Caurie adsorption equation and it depends on the number of component ingredients and the initial moisture contents of the ingredients in the mixture. Solute and non‐solute/water interaction effects in solution were identified as playing important roles in determining accurate equilibrium A_ws of the aqueous mixtures. The new equation allows for interaction effects in mixed solution/suspensions and has been tested on model foods (the data was taken from the literature) containing up to five solutes and non‐solute components. The equation displays a high degree of accuracy. Unlike the Ross equation, which applies only approximately to mixtures of dilute solutions, the new equation applies to mixtures at all solution concentrations and to wet solids.     

Enhanced substantivity of hyaluronic acid on keratin substrates via polymer complexation

Complexes of glycosaminoglycans and certain cationic polymers have been identified which provide utility in skin and hair care applications. The combination of biologically engineered hyaluronic acid and the cationic cellulose polymer, polyquaternium-10, results in a unique, stable, multifunctional, association complex with enhanced polymer functionality. Complexation of the anionic and cationic polysaccharide polymers renders hyaluronic acid substantive to keratin, as evidenced by zeta potential changes of the surface charge of hair via electrokinetic streaming potential measurements. Radiolabelling techniques show as much as a ten-fold increase in bound hyaluronic acid on hair after water rinsing. The resulting 'enhanced'substantivity of hyaluronic acid, as part of the complex, thus extends the time hyaluronic acid remains in contact with keratinous surfaces, prolonging its humectant, moisturizing and skin-smoothening effects.     

响应面优化烟叶多糖磷酸化工艺 及保润性评价

采用超声辅助提取烟叶多糖,在单因素基础上,以响应面法优化磷酸化烟叶多糖的工艺条件,再分别以磷酸化烟叶多糖、烟叶多糖、蒸馏水和丙二醇为保润剂,对比其在烟丝上的持水性能,最后,对烟叶多糖和磷酸化烟叶多糖进行评吸。结果表明:制备磷酸化烟叶多糖的最佳工艺条件为:反应时间6.1 h、反应温度95℃、pH=9.0,磷酸化烟叶多糖中磷酸根质量分数平均为11.68%。持水性能大小为磷酸化烟叶多糖烟叶多糖丙二醇蒸馏水。感官评价结果显示:添加磷酸化烟叶多糖对改善卷烟评吸品质效果显著。     

化妆品常用保湿剂保湿吸湿性能研究

当保湿滋润成为当今世界日化产品的基本功能诉求时，如何在层出不穷的保湿剂成分中选用合适的产品，确保这一功能的体现，这便是摆在我们面前必须要考查的重点之一。通过对产品自身吸湿性与保湿性的相关测试，为优选各种保湿剂提供了依据。     

Synthetic hectorite – a new toothpaste binder

The use of the synthetic inorganic colloid ‘Laponite’ as a toothpaste binder is reviewed. Variables examined include the effect of polishing agent, humectant type and cellulosic co-binder. Results indicate that stable pastes may be prepared using a blend of Laponite and sodium carboxymethyl cellulose with a small reduction in overall binder level. The maximum binder reduction is achieved using sorbitol as the sole humectant. A simple comparison test also indicates that flavour level may be reduced by up to 25%. L'hectorite synthetique – un nouveau liant pour dentifrices     

乙二醇葡糖苷的合成及保湿性研究

在磷酸催化下 ,由葡萄糖和乙二醇经缩醛化反应制备了乙二醇葡糖苷 ,可用作化妆品保湿剂。采用高效液相色谱跟踪监控反应进程 ,并确定了乙二醇葡糖苷的组成。反应在 130℃、5 3kPa下进行 ,减压蒸除反应生成的水。醇糖的量比是 3∶1或 5∶1,催化剂占葡萄糖质量的 2 % ,过量乙二醇在 4 0 0～ 0 6 7kPa下减压蒸除 ,残糖质量分数小于 1%。合成的乙二醇葡糖苷具有优良的保湿性能 ,当m (羟乙基葡糖苷 )∶m (乙二醇二葡糖苷 ) =0 73∶1 0 0时 ,质量分数为 70 %的乙二醇葡糖苷水溶液的保湿能力比质量分数为 70 %的甘油水溶液高 11 1%。羟乙基葡糖苷的含量越高 ,产品的保湿性越好。     

复合型保润剂对膨胀烟丝感官品质和保润性能的影响

为了研究复合型保润剂对膨胀烟丝的影响,采用膨胀前加料方式,按0．1％的施加比例加料制备膨胀烟丝,并进行物理指标、感官品质和保润性能对比．结果表明,添加复合型保润剂的膨胀烟丝与空白样品相比,物理指标得到明显提高,长丝率由43．4％提高到50．8％,整丝率由69．7％提高到74．1％,填充值由2．163 mm／g提高到2．463 mm／g,而碎丝率则由2．8％降低到2．1％;膨胀烟丝感官品质由65．0分提高到68．8分;保润性能得到明显改善,平衡含水率提高,失水速率降低．     

Role of Moisture in Maillard Browning Reaction Rate in Intermediate Moisture Foods: Comparing Solvent Phase and Matrix Properties

ABSTRACT: In intermediate-moisture foods, a mechanism describing how moisture affects chemical reaction rate is unknown. Previously, research showed glycol addition to model systems allowed high rates of nonenzymatic browning below the monolayer moisture value and an a_w of 0.2. These works were replicated, focusing on a mechanism of either plasticization or reactant dissolution. T_g curves showed plasticization increased with added glycerol and sorbitol. The maximum rate of nonenzymatic browning with glycerol occurred at an a_w= 0.25 and was 1.5 times higher than the control (a_w= 0.65). Sorbitol showed rates similar to the control. Plasticization and aw were poor predictors of reaction rate. Dissolution of glucose in glycerol explained the effect.     

保润剂对烟草叶表面微结构的影响

为调查添加保润剂后烟草表面微结构的变化情况,采用XL30-ESEM型环境扫描电子显微镜技术,对添加木糖醇、山梨醇、丙二醇、丙三醇和芦荟多糖5种保润剂烟草的上表皮、下表皮和断面进行了研究。结果表明,保润剂均能使烟样的水分含量极显著增加,添加保润剂的烟草叶表面沟槽纹理发生变化,其中C2F上表皮处理样品的沟槽纹理面积比列均显著增加。处理样品气孔的保卫细胞除山梨醇和芦荟多糖的X2F下表皮不显著外,其他均有显著膨大。丙二醇、丙三醇和木糖醇对气孔宽度的缩小和气孔平均面积的减少均有显著影响。保润剂处理的烟样断面厚度均显著高于对照。总体比较,丙二醇和丙三醇对叶表面微结构的影响较大,其他排序是木糖醇、芦荟多糖和山梨醇。     

卷烟保润技术研究进展

保润技术是我国烟草行业未来几年科技研究和科技创新的主要方向之一,从保润剂、辅料保润技术、保润工艺3个方面综述卷烟制品保润技术研究进展,并对其发展进行了展望.