玉米淀粉与黄原胶复配体系糊化及回生特性的研究

本文研究了玉米淀粉与黄原胶复配体系的糊化和回生特性。RVA糊化实验表明黄原胶降低了玉米淀粉的成糊温度,并随着黄原胶在复配体系中的比例逐渐增加,其复配体系的峰值黏度和终值黏度均显著增加(p<0.05),崩解值和回生值降低(p<0.05)。热稳定性实验表明加入黄原胶后的复配体系在95℃之后的高温下可以较长时间维持体系的黏度,具有良好的热稳定性。凝沉性实验表明黄原胶可以降低玉米淀粉的凝沉作用,当m(玉米淀粉)∶m(黄原胶)为9∶1时复配体系凝沉作用最小,在120h后仍无明显上清液析出。冻融稳定性实验表明黄原胶能抑制复配体系的回生,提高其冻融稳定性。     

刺槐豆胶与黄原胶复配体系的流变性

研究刺槐豆胶/黄原胶复配体系的流变性,并采用流变学的Cross模型进行拟合分析。结果表明:刺槐豆胶与黄原胶复配可以产生协同作用,当刺槐豆胶与黄原胶的复配体积比为4∶6时,复配体系的黏度最大,触变测试中形成的滞后环面积最大,并且在黏弹性测试中储能模量G’表现出最大值。因此,刺槐豆胶与黄原胶的最佳复配比例为体积比4∶6。对最佳比例复配体系进行不同温度处理后测试可知,最佳复配体系的最适处理温度为80℃,得到的复配体系黏度最大;复配体系的p H值在6.0~10.0之间时,其黏度变化较小,保持相对稳定。     

荠蓝胶功能特性的研究

研究荠蓝胶的黏度、起泡性、乳化性和复配性,并与几种常用的食品胶作比较。结果表明:低浓度的荠蓝胶即表现出很高的黏度值,浓度增加,其起泡能力和泡沫稳定性以及乳化稳定性增加,乳化性则随浓度增加先升高后下降。荠蓝胶与黄原胶和瓜尔胶复配增稠最佳质量比为荠蓝胶:黄原胶=5:5,荠蓝胶:瓜尔胶=9:1。通过复配,荠蓝胶耐剪切性得以提高,性能良好。     

黄原胶与阴离子瓜尔胶复配溶液的流变特性研究

配制总质量分数为1%的黄原胶与瓜尔胶复配溶液,两者比例分别为0.1%∶0.9%,0.2%∶0.8%,0.3%∶0.7%,0.4%∶0.6%,0.5%∶0.5%,0.6%∶0.4%,0.7%∶0.3%,0.8%∶0.2%,0.9%∶0.1%。通过稳态流动、应变扫描、频率扫描以及动态黏弹性温度扫描与动态黏度温度扫描,观察复配比例对复配溶液的黏度特性随剪切速率及温度的变化情况,黏弹性随应变、频率及温度的变化情况。黄原胶与瓜尔胶通过分子间缠绕或者分子间次级键的相互作用起到增稠协同作用,说明两者复配有利于零剪切黏度、黏度及黏弹性能的增加。在低剪切区域与低频率区域主要呈现黄原胶的贡献,而在高剪切区域与高频率区则以瓜尔胶起主导作用。对复配溶液的频率扫描中G′大于G″,表现类固态的性质。另外,在5~90℃温度范围,G′G″,复配溶液表现出凝胶状态,呈完善的网络结构;同时,黏度随温度的升高而逐步降低,不存在构象转变温度。     

黄原胶对木薯淀粉糊化特性及其糊稳定性的影响

研究黄原胶对木薯淀粉糊化特性,热、酸条件下的黏度稳定性及冻融稳定性的影响。结果表明：复配体系的峰值黏度、热糊稳定性、冷糊稳定性显著提高;黄原胶能明显改善木薯淀粉耐热和耐酸稳定性;抑制淀粉的回生,提高淀粉的冻融稳定性;通过电子显微镜观察木薯淀粉颗粒结构变化,进一步验证了黄原胶对木薯淀粉糊化特性及稳定性的改善作用。     

钙离子对黄原胶溶液耐酸性、耐热性的影响

为了研究Ca2+对黄原胶性能的影响,选用两种钙含量的黄原胶,分析了黄原胶分子中Ca2+对其黏度的影响.分别向0.2％、1.0％的两种黄原胶样品溶液中添加不同浓度的CaCl2,以低剪切黏度为指标,考察溶液中Ca2+浓度对黄原胶的耐酸性和耐热性的影响.实验结果表明:高钙黄原胶耐酸性和耐热性优于低钙黄原胶,足够的Ca2+浓度有利于提高黄原胶的耐酸性和耐热性.本研究结果能够为后期生产中黄原胶性能改良和在产品中的应用提供理论依据.     

一株野油菜黄单胞菌产黄原胶的性质

通过发酵一株野油菜黄单胞菌得到黄原胶,进而测定该黄原胶在不同质量浓度、pH值、氯化钠质量浓度、温度下黏度变化,分析黄原胶流变特性、丙酮酸质量分数和黏均分子质量。结果表明：本实验菌株的黄原胶产量达到28.4 g/L,黄原胶黏度在质量浓度高于4.0 g/L时迅速升高,黄原胶黏度在pH 3.0～10.0之间稳定。氯化钠质量浓度由10 g/L增加到70 g/L时,使1.0 g/L黄原胶黏度提高20%,而温度高于35 ℃时使1.0 g/L黄原胶黏度降低。黄原胶的丙酮酸质量分数达到6.35%,黏均分子质量为5.7×106 D。1.0 g/L黄原胶的稠度系数和流体指数分别为26.94和0.765 5,5.0 g/L黄原胶的稠度系数和流体指数分别为489.65和0.328 1。研究表明该株野油菜黄单胞菌具有较大的潜在应用价值。     

盐对马铃薯淀粉及马铃薯淀粉-黄原胶复配体系特性的影响

研究不同种类以及不同浓度的盐对马铃薯淀粉以及马铃薯淀粉-黄原胶复配体系糊化性质以及流变学性质的影响。结果表明：盐的加入均增加了马铃薯淀粉的成糊温度和回值,降低了峰值黏度、终值黏度和崩解值,且马铃薯淀粉糊的黏度值随着盐浓度的增加先降低后升高,成糊温度随着盐浓度的增加呈现先显著升高后略微下降的趋势。对于马铃薯淀粉-黄原胶复配体系,盐的加入升高了复配体系的成糊温度、峰值黏度和崩解值,并且复配体系的黏度值随着盐浓度的增加而增加。流变学性质表明盐引起马铃薯淀粉糊的假塑性增强,并随着盐浓度的增加假塑性先增强后略有减弱,相反盐引起马铃薯淀粉/黄原胶复配体系的假塑性减弱,并与盐浓度之间没有明显的规律性。     

黄原胶对莲藕淀粉糊化性质及流变与质构特性的影响

为探究亲水性胶体对淀粉性质的影响,将不同比例的黄原胶添加到莲藕淀粉中,研究两者复配后莲藕淀粉的糊化、流变、质构特性及微观结构的变化。结果表明：黄原胶提高了淀粉糊终值黏度、糊化峰值时间并降低淀粉的崩解值和回生值,复配体系有更好的热稳定性和抗老化性。添加不同比例的黄原胶使莲藕淀粉糊的剪切应力不同程度降低,稠度系数K增大,流体指数n降低,加入黄原胶后的淀粉糊仍为假塑性流体,但是具有更好的增稠作用;加入黄原胶提高了淀粉的贮能模量、损耗模量,降低了损耗角正切值tanδ,体系的黏弹性和稳定性增强,其中莲藕淀粉与黄原胶配比为8.0∶2.0（g/g）的复配体系增稠效果、黏弹性、稳定性最好。复配体系的硬度、内聚性、黏着性、咀嚼性降低,弹性略有增大,添加黄原胶形成的凝胶质地更柔软。扫描电子显微镜观察到添加黄原胶后淀粉内部形成更加均匀稳定的结构。     

猪屎豆胶与黄原胶复配胶的流变性研究

本实验主要通过测定体系黏度研究了猪屎豆胶与黄原胶复配胶的流变学性质。实验结果表明,猪屎豆种子胶与黄原胶有较强烈的协效性,二者的最佳复配比为6：4;复配胶的黏度随浓度的升高而升高,浓度达到0．4％时开始形成凝胶,浓度达到0．8％时形成坚实的凝胶,浓度为0．7％时的溶液黏度为5367mPa&#183;s;混合胶液为“非牛顿流体”,溶液具有“假塑性”;胶液的最佳加热温度为80℃,最佳加热时间为1h;pH5～9、冻融变化、苯甲酸钠、超声波和微波处理对对其黏度影响较小;复配胶具有良好的耐盐稳定性。     

Viscosity of guar gum and xanthan/guar gum mixture solutions

The viscosity of diluted guar gum solutions and the viscosity of xanthan and guar gum mixture solutions have been studied. Guar gum solutions showed pseudoplastic behaviour. Apparent viscosity increased with gum concentration and decreased with the temperature at which viscosity was measured. A maximum in the plot of viscosity versus increasing dissolution temperature was observed at 60 °C. This behaviour was related to differences in molecular structure of the polymers solved at different temperatures. Mixtures of xanthan and guar gum showed a higher combined viscosity than that occurring in each separate gum. This synergistic interaction was affected by the gum ratio in the mixture and dissolution temperature of both gums. The effect of polysaccharide concentration (1.0, 1.5 and 2.0 kg m⁻³), xanthan/guar gum ratio (1/5, 4/2, 3/3, 4/2 and 5/1) and dissolution temperature (25, 40, 60 and 80 °C for both gums) on the viscosity of solutions of mixtures were studied. The highest viscosities were observed when 2.0 kg m⁻³ gum concentration was used together with a ratio of xanthan/guar gum of 3/3 (w/w) and dissolution temperature of 40 and 80 °C for xanthan and guar gum, respectively. © 2000 Society of Chemical Industry     

Swallowing profiles of food polysaccharide solutions with different flow behaviors

The relationship between physiological response and sensory perceived scores in swallowing was investigated using food polysaccharide solutions. Solutions from xanthan gum (0.3–0.9%) and locust bean gum (0.5–0.8%) were used as specimen with different flow behaviors identified by static and dynamic rheological methods. Acoustic analysis and sensory evaluation were carried out to investigate the swallowing profiles using the same human subjects. From acoustic analysis, time required for bolus to transfer through the pharyngeal phase t₂ decreased with increasing concentration of xanthan gum despite the viscosity increase. Also, the acoustic balance for the swallowing sound shifted to a higher frequency range with increasing concentration. The t₂ for locust bean gum was much less concentration-dependent and consistently larger than that for xanthan gum when compared at equivalent shear viscosity at 10 s⁻¹. Also, the acoustic balance for the swallowing sound was less concentration-dependent than that for xanthan gum. From sensory evaluation, 0.6% xanthan gum was scored the highest in perceived swallowing ease, while 0.75% locust bean gum was scored the lowest. Both t₂ and the acoustic balance correlated well with perceived swallowing ease. Results indicate that xanthan gum solutions flow as one coherent bolus through the pharyngeal phase with smaller variation of flow velocity than locust bean gum solutions, leading to a greater sensation of swallowing ease. “Structured fluid”, defined as fluid with yield stress such as xanthan gum solutions, is a rheological nature that allows bolus to be swallowed in one go, relating to perceived swallowing ease of liquid foods.     

葫芦巴胶改善吞咽障碍者饮水安全性的流变学研究

参照美国吞咽障碍膳食标准,以样品的 η50黏度为分类依据,将葫芦巴胶制备成黏度分别为180 cP(花蜜型)、1000 cP(蜂蜜型)和2500 cP(布丁型)的增稠流体,对其流变学性质进行研究,并评价葫芦巴胶用于改善吞咽障碍者的饮水安全性.结果表明,溶解温度是葫芦巴胶流变性质能否满足改善饮水安全性要求的关键.80℃制备...     

3种改良剂种类对小麦复配粉粉质特性及面片品质影响的比较分析

为改善市售小麦粉（蛋白质11%）制作汤饭面片的面团特性和品质,在小麦粉中添加不同磷酸盐、食用胶类和淀粉,测定复配粉的糊化特性、面团特性以及面片复水后的品质比较。结果表明,磷酸盐能增加面粉峰值粘度、最低粘度、最终粘度、衰减值和回生值,对峰值时间、糊化温度影响不显著（p>0.05）。焦磷酸钠和三聚磷酸盐显著增加了面粉峰值粘度（p<0.05）;聚丙烯酸钠显著降低了面粉回生值和衰减值（p<0.05）,分别为767 cP、593 cP;马铃薯变性淀粉、木薯变性淀粉显著降低了面粉的回生值（p<0.05）。磷酸盐、食用胶对面团粉质特性有显著提高,淀粉降低了面团的粉质特性。六偏磷酸钠、三聚磷酸盐和焦磷酸钠弱化度最低,都为4 BU;聚丙烯酸钠、黄原胶弱化度最小分别为1 BU、4 BU。3种改良剂均能改善面片的剪切特性,除碳酸氢钠其他试验组能有效改善面片复水性和感官。三聚磷酸盐、黄原胶和马铃薯变性淀粉在试验组中对面片的硬度和延展性更好,复水性、品质和适口性更佳。综合评价：添加三聚磷酸盐、黄原胶和马铃薯变性淀粉能够较好的改善面团的特性和面片的品质,并能制作出适合加工新疆汤饭的方便面片。     

黄原胶流变学特性的研究

分别研究了黄原胶浓度、温度、热处理时间、pH值、抗氧化剂VC、氧化剂H2O2、金属离子以及大豆分离蛋白对黄原胶黏度的影响.实验结果表明,随着黄原胶浓度的增大,黏度增大直至基本不变;温度、热处理时间使其黏度稍微有所下降:pH值为6.0时,黏度最大;抗氧化剂VC、氧化剂H2O2使黏度降低;随着金属离子Na+、Fe2+浓度的增大,黄原胶黏度呈下降变化;大豆分离蛋白使黄原胶黏度有所增加.     

Viscosity of solutions of xanthan/locust bean gum mixtures

Xanthan and locust bean gums are polysaccharides able to produce aqueous solutions with high viscosity and non‐Newtonian behaviour. When these solutions are mixed a dramatic increase on viscosity is observed, much greater than the combined viscosity of the separated polysaccharide solutions. In this work the influences of different variables on the viscosity of solutions of mixtures of xanthan/locust bean gum have been studied. Total polysaccharide concentration, xanthan and locust bean ratio on mixture and temperature at which the gum was dissolved (dissolution temperature) for both xanthan and locust bean gums have been considered. Under these different operational mixture conditions shear rate and time have also been considered to describe the rheological behaviour of the solutions studied. The high viscosity increase observed in these mixtures is due to the interaction between xanthan gum and locust bean gum molecules. This interaction takes place between the side chains of xanthan and the backbone of the locust bean gum. Both xanthan molecule conformation in solution – tertiary structure – and locust bean gum structure show great influence on the final viscosity of the solution mixtures. Xanthan conformation changes with temperature, going from ordered structures to disordered or chaotic ones. Locust bean gum composition changes with dissolution temperature, showing a dissolved galactose/mannose ratio reduction when temperature increases, ie the smooth regions – zones without galactose radicals – are predominantly dissolved. The highest viscosity was obtained for the solution mixture with a total polysaccharide concentration of 1.5 kg m⁻³ and a xanthan/locust ratio of 2:4 (w/w) and when xanthan gum and locust bean gum were dissolved at 40°C and 80°C, respectively. © 1999 Society of Chemical Industry     

黄原胶对玉米淀粉糊化性能的影响

将黄原胶引入到淀粉浆料中,采用快速黏度分析法(RVA)研究了黄原胶的加入对玉米淀粉糊化性能和浆液表观黏度的影响,讨论了黄原胶与玉米淀粉分子之间的相互作用.结果表明:黄原胶可促进淀粉糊化,降低淀粉的糊化温度,缩短糊化时间;随着黄原胶质量分数的增加,淀粉的糊化峰值黏度增加,表现了2种高分子的相互作用;黏度衰减值随黄原胶增加...     

Effect of Freezing on Functional and Textural Attributes of Cress Seed Gum and Xanthan Gum

Consumer habits have undergone great changes, motivated by the new social lifestyle. These changes have promoted the increase in the production of frozen foods; and as a result, many food applications of some hydrocolloids are limited due to functional loss during freezing. In this study, the effect of freezing treatments (?18 °C for 24 h and ?30 °C for 15 h) on rheological, emulsifying, foaming, and textural characteristics of cress seed gum as a new source of hydrocolloid in comparison with xanthan gum as a commercial gum were investigated. The results demonstrated that cress seed gum had significantly lower viscosity than xanthan gum solution, and the freezing treatments did not have significant impact on rheological properties of both products. Conversion of water to ice leads to an increment in molecular association and improved textural characteristics. The high tendency of cress seed gum chains to associate is attributed to its high mannose to galactose ratio. High stability of cress seed gum and similarity with xanthan gum make it attractive for use in frozen foods as a novel gum to provide specific functionality, minimize the negative effect of freezing, and reduce production costs.