不同条件下锦橙皮渣果胶的黏度分析

以传统酸提取法从榨汁后锦橙皮渣中提取的果胶为研究对象,研究在不同果胶质量浓度、温度、pH值、蔗糖质量浓度、NaCl浓度和钙离子浓度条件下,果胶溶液的黏度随剪切速率的变化情况。结果表明:锦橙皮渣果胶溶液是典型的假塑性非牛顿流体,随着温度的上升,果胶溶液的黏度不断下降,在100℃条件下,果胶溶液表现出了牛顿流体的性质。在较高和较低pH值环境下都会导致果胶溶液黏度的下降。果胶溶液的黏度随着蔗糖质量浓度和钙离子浓度的增加而增大,而随NaCl浓度的增加先增大后减小。     

食品增稠剂瓜儿豆胶性质及复配性的研究

本文对瓜尔豆胶的流变性,浓度、温度、pH值、电介质对粘度的影响,与黄原胶、卡拉胶复后粘度变化进行了初步研究。结果表明,低浓度瓜儿豆胶属非牛顿流体中假塑性流体,其粘度随浓度升高而上升,随温度升高而下降,几乎不受pH值影响,对NaCl和低浓度Ca~(2+),Al~(3+)有良好兼容性,与卡拉胶复配无增效作用,而与黄原胶复配增效显著,复配最佳比例为瓜儿豆胶:黄原胶=0.6:0.4     

卡拉胶溶液在低浓度时的流变性能及其影响因素研究

以低浓度卡拉胶溶液为研究对象,考察了其流变性能及浓度、剪切速率、温度、pH值、搅拌时间对溶液黏度的影响。结果表明,低浓度卡拉胶溶液的黏度随浓度的增大而增加;溶液呈现假塑性,表现出剪切稀化的特点;其黏度先随温度的升高逐步上升,当温度升高到一定程度时,溶液黏度开始下降;在酸性条件下(pH<5.0)其黏度随pH的增大而下降,在接近中性时基本稳定,随后又下降;低浓度卡拉胶溶液在不同的搅拌时间作用下具有不同的黏度。     

硫酸酯化香豆胶的制备、表征及其性质

通过单因素和正交试验获得硫酸酯化香豆胶的优化工艺参数:香豆胶添加量为7 g,反应温度为0℃,浓硫酸添加量为3mL,正丁醇添加量为6mL.红外光谱分析表明,该条件下硫酸基已经与半乳甘露聚糖结合成酯.酯化后的香豆胶分子粒径减小,黏度降低,且随取代度的增大而下降,表现出较好的溶解性、透明度.冷水溶和热水溶硫酸酯化香豆胶溶液的表观黏度都随浓度的升高而呈指数规律的上升;酯化香豆胶溶液为非牛顿流体,随着温度的升高,表观黏度下降,具有耐热性;酯化香豆胶溶液在碱性条件下较为稳定;冻融处理可使酯化香豆胶溶液的表现黏度下降.     

荸荠淀粉糊粘度特性研究

测定了荸荠淀粉糊的Brabender 黏度曲线,利用NDJ-8S数字显示黏度计研究了淀粉乳浓度、pH值、增稠剂、糖、盐等因素对荸荠淀粉糊黏度的影响以及荸荠淀粉糊的流变性。实验结果表明,荸荠淀粉糊化温度低,峰值黏度大,冷稳定性优良,不易发生老化,但热稳定性差。荸荠淀粉糊的黏度随淀粉浓度增加而呈幂次方上升;酸使糊黏度下降,碱使糊黏度上升;黄原胶与魔芋胶均使淀粉糊的黏度增加;葡萄糖和蔗糖对糊黏度的影响呈现先上升后下降的趋势;NaCl与CaCl2均能降低淀粉糊的黏度。荸荠淀粉糊属于非牛顿假塑性流体。     

玉米淀粉糊流变特性研究

利用AR–500流变仪,研究了不同质量浓度、温度和加热时间条件下玉米淀粉糊的流变特性。结果表明:玉米淀粉糊主要表现为假塑性非牛顿流体,流变特性服从Carreau模型。在同一剪切速率下,黏度随着质量浓度增大而增大,随着温度升高而降低,随着加热时间延长而下降;在同一质量分数条件下,黏度随着剪切速率的增加而呈现先增加后降低的趋势;在同一温度条件下,黏度随着剪切速率的增加而降低。     

米糠膳食纤维溶液流变特性研究

用ARES高级扩展流变仪测试了不同因素对米糠膳食纤维溶液流变特性的影响。结果表明:米糠膳食纤维溶液在不同处理条件下均呈现假塑性流体特性,符合幂定律;大颗粒对米糠膳食纤维溶液的表观黏度和剪切应力影响较小;米糠膳食纤维溶液黏度随着它的浓度增加而上升;8%米糠膳食纤维溶液的黏度不受NaCl溶液浓度的影响,但受CaCl2溶液浓度的影响;米糠膳食纤维溶液的表观黏度和剪切应力均随温度的升高而下降。     

凉粉草胶的稳剪切流变学性质

研究了凉粉草胶在不同质量浓度、温度、pH、盐的种类及盐浓度和不同蔗糖浓度下的流体行为以及固定剪切速率下的表观粘度随不同条件的变化情况。结果表明,凉粉草胶溶液在不同的条件下呈牛顿流体或假塑性流体行为,在剪切速率52.8s-1下,10 g/dL凉粉草胶溶液的表观粘度随胶质量分数(1~20 g/dL)的增加而递增,随温度(25~70℃)的升高而递减,随pH(5~12)的变化则不具有单调性,随NaCl(0~3.0 g/dL)的添加而递减,随CaCl2(0~3.0 g/dL)的添加则先减小后增大,随蔗糖(10~50 g/dL)的添加则递增。     

pH值、NaCl浓度和加热温度对猪肉匀浆物凝胶质构特性的影响

采用二次通用旋转试验设计,研究了pH值、NaCl浓度和加热温度对猪后腿肉匀浆物热诱导凝胶质构特性的影响。结果表明:不同处理条件对凝胶质构特性的影响存在差异。不同加热温度下,pH值和NaCl浓度对凝胶硬度、弹性、内聚性、胶粘性和咀嚼性影响的总体趋势一致且两者存在明显的交互作用。pH值较低时,随着NaCl浓度的增加,凝胶的硬度、弹性、内聚性、胶粘性和咀嚼性均增大;pH值较高时,NaCl浓度对凝胶硬度、弹性和胶粘性影响较小,内聚性随着NaCl浓度增加而降低。同时,随着加热温度的升高,凝胶的硬度和胶粘性增大,内聚性和咀嚼性减小,而凝胶弹性变化较小。     

皂荚豆胶冷水溶部分和热水溶部分的流变性研究

本研究对皂荚豆胶冷水溶和热水溶部分的流变性进行了研究。研究结果表明:浓度、温度、剪切力、pH值、冻融等变化对皂荚豆胶的粘度有较大影响;皂荚豆胶与黄原胶、卡拉胶具有明显的协效性;皂荚豆胶在冷水和热水中溶解,其流变性有所不同。     

紫甘薯全粉流变学特性的研究

以紫甘薯全粉为原料,研究其在不同加工条件如剪切速度、加热、pH值、盐浓度、蔗糖浓度等影响下的流变学特性.结果表明:紫甘薯全粉溶液的黏度随加热时间的延长和溶液浓度的增加而增大;随温度的升高与剪切速率的增加而减小;pH值、盐浓度等对其黏度也有很大影响.     

影响沙蒿籽胶表观黏度的因素

利用响应面法和控制变量法分析沙蒿籽胶溶液表观黏度受温度、溶液体积分数、pH值和盐离子的影响变化,同时研究了添加不同比例增稠剂海藻酸钠、魔芋胶、羧甲基纤维素（carboxyl methyl cellulose,CMC）和卡拉胶对沙蒿籽胶溶液表观黏度的影响。结果表明：温度对沙蒿籽胶表观黏度影响不大;随溶液体积分数的增加沙蒿籽胶溶液的表观黏度增加;pH值在3.0～9.0时,沙蒿籽胶溶液表观黏度随pH值的上升而增大;加入盐会使沙蒿籽胶黏度有不同程度的下降,不同阳离子对其黏度影响的强弱为Fe3＋＞Ca2＋＞Mg2＋＞Na＋;沙蒿籽胶与CMC复配后,具有黏度增强的效果。     

盐及非盐物质对常用低浓度食品胶溶液粘度影响的研究

对饮料生产中常用的食品胶－黄原胶、海藻酸钠、瓜尔胶和琼脂在低浓度水相体系中外加盐（阴、阳离子）、乙醇、蔗糖及柠檬酸对溶液粘度的影响作了探讨性研究,结果表明四种胶溶液（０．１０％黄原胶、０．３０％海藻酸钠、０．２５％瓜尔胶、０．１０％琼脂）中、瓜尔胶溶液对盐的耐受性最好,即大多数阴阳离子都不会对其粘度产生影响,而常用金属盐阳离子及Ｃｌ＾－、ＳＯ３＾２－对黄原胶溶液粘度的影响与阴阳离子对海藻酸钠和琼脂     

皂荚籽热风干燥特性及干燥动力学模型研究

目的:为了研究皂荚籽干燥特性,为其机械化剥离应用提供理论参考。方法:研究了不同温度(70、90、110与130℃)与不同预处理方法(清水、碳酸氢钠溶液、焦磷酸二氢二钠溶液和酒石酸氢钾溶液浸泡)对皂荚籽干燥动力学的影响,使用Lewis模型、Page模型与Weibull分布函数对其干燥特性曲线进行非线性拟合并进行评价,并通过应面回归模型建立起干燥动力学模型。结果:皂荚籽干燥过程存在明显的升速降速段,且干燥温度越高,干燥速率越快,预处理方法对其干燥速率有一定影响。通过比较各模型的分别是决定系数()、卡方检验值()、残差平方和()与均方根误差(),结果显示Weibull分布函数能更好地模拟皂荚籽干燥过程,形状参数()随温度的升高而降低,尺寸参数()与预处理方法有关。计算了皂荚籽干燥过程的有效水分扩散系数()及其估算值()与活化能(),水分扩散系数及其估算值随着温度的升高而升高,经过酒石酸氢钠溶液预处理的皂荚籽的活化能低于其它预处理方法,可大大提高皂荚籽干燥效率。结论:经碳酸氢钠溶液预处理的皂荚籽干燥较容易发生,Weibull函数能较好地描述皂荚籽干燥过程中水分含量的变化规律,酒石酸氢钠溶液可以降低皂荚籽的活化能。该研究可为皂荚籽干燥提供理论和技术基础。     

Functional Properties of Flax Seed Mucilage

Flax seed (Linwn usitatissimum L.) mucilage was prepared by extraction of seeds with water followed by evaporation, precipitation with ethanol and freeze drying of extract. Proximate composition, solubility, foamability and moisture sorption characteristics were determined. The mucilage contained less carbohydrates, more minerals and more protein than commercial locust bean and guar gums. Its solubility, however, was higher than locust bean and guar gums, and lower than gum arabic. Flax seed mucilage exhibited good foam stability properties in aqueous solutions at 1.0% (w/v). Very diluted solutions exhibited Newtonian-like behavior while shear thinning was shown at concentrations above 0.2% (w/v). The viscosity was maximum at a pH range 6.0–8.0 and it was reduced in solutions containing NaCl.     

Studies on the steady shear flow behavior and functional properties of Lepidium perfoliatum seed gum

Flow properties of Lepidium perfoliatum gum, extracted from Qodume shahri seeds, as influences of concentrations (0.5%, 1%, 1.5% and 2%), temperatures (5, 25, 45, and 65 °C), salts and pHs were investigated. Among the selected models, power law model well described the rheological behavior of the L. perfoliatum seed mucilage solutions with high determination coefficients, R² and low root mean square error (RMSE). Non-Newtonian shear thinning behavior was observed at all temperatures and concentrations. While increase in temperature decreased the viscosity and increased the flow behavior indices, adverse effect was obtained by increasing the concentration. The temperature effect was more pronounced at 0.5% L. perfoliatum seed gum concentration and indicated the higher activation energy (E_a: 31614.56 J/mol). The viscosity was dependent on type of salt addition, and decreased with salt concentration. This behavior was more evident when using divalent salt. A marked dependence of viscosity on pH was also observed, as pH increased from acidic to alkaline conditions, the viscosity increased until pH of 9 and afterward decreased. The hydrocolloid showed good water absorption capacity (WAC) and imparted relatively high stability to foam and oil-in-water emulsion. However, the gum solubility was low at all temperatures studied (30, 60 and 90 °C).     

橙皮果胶流变学性质的影响因素

以采用离子交换树脂法从橙皮中提取的果胶为研究对象,研究浓度、温度、pH、金属离子Ca2+、糖、盐等对果胶流变性质的影响.结果表明:橙皮果胶溶液的黏度随剪切速率的增加而降低,为典型的非牛顿流体.这种剪切稀化现象受果胶溶液黏度的影响.随着果胶浓度的增大,浓度对果胶溶液流变学性质的影响增强.当热处理一定时间后果胶溶液黏度急剧下降直至表现出理想的牛顿流体性质;偏酸或偏碱环境下都导致果胶溶液黏度下降且碱性条件下降低更显著;果胶分子间疏水作用的增强使果胶溶液的黏度降低,共聚物之间氢键的形成受到抑制会使果胶溶液的黏度降低,较强的静电作用可以增强果胶网络结构的强度,使果胶溶液黏度升高.     

Viscoelastic Characterization of Sage Seed Gum

Wild sage seed is a small, rounded, and mucilaginous seed, which comes from Salvia macrosiphon. The viscoelastic behavior of sage seed gum, at different concentrations (0.5–2%, w/w), was examined by measuring the transient (in-shear structural recovery and creep/recovery tests) and dynamic (stress and frequency sweeps) rheological properties. The mechanical spectra showed typical weak gel behavior at all concentrations, with storage modulus higher than loss modulus, and little variation with frequency. Both moduli greatly increased with increasing the concentration, and the concentration dependency was well described by the power-law model. The loss tangent was increased slightly with increasing the frequency in the range of 0.25–0.67, although it was not affected by an increase in gum concentration. Moreover, the complex viscosity was found to increase with the increase of sage seed gum concentration and to decrease linearly with the increase of frequency. All samples showed typical viscoelastic response to stress in creep/recovery tests, with recoverable strain increasing in direct proportion to sage seed gum concentration. Creep curves were adequately fitted with a Burger model of four parameters. The elastic and viscous contributions to the general viscoelastic behavior were analyzed through the obtained parameters. The concentration had no specific effect on the in-shear recovery properties of sage seed gum gels, and the gel structure was highly recovered after applying shear. The results of this article indicated that sage seed gum may offer an excellent alternative for commercial gums as a thickening/gelling agent.