酸催化水解阿拉伯胶制备L-阿拉伯糖工艺

阿拉伯胶是提取制备L-阿拉伯糖的理想原料,对阿拉伯胶进行酸催化水解可获得含L-阿拉伯糖、D-半乳糖、L-鼠李糖的反应液,优化酸水解条件使水解液中L-阿拉伯糖的含量和收率均达到最佳水平,是保证后续分离纯化工艺稳定性及产品品质的关键。利用单因素实验考察了反应时间、酸浓度、反应温度、固液比等因素对水解工艺的影响,获得了影响酸水解反应的关键因素及适宜的水解条件。结果表明:温度对L-阿拉伯糖的生成速率有明显影响。经优化,当固液比为1:10 (g/ml)、100℃、0.1 mol·L^-1 H₂SO₄水解90 min或90℃、0.1 mol·L^-1 H₂SO₄水解200 min,水解液中L-阿拉伯糖的相对纯度分别达85%和87%,水解收率高达85%。     

L-阿拉伯糖研究进展

L-阿拉伯糖是一种新兴的低热量功能性糖,在自然界中,广泛存在于玉米皮、甜菜根、阿拉伯胶等中。L-阿拉伯糖在血糖、血脂的调节方面有广阔的前景。本文综述了L-阿拉伯糖的制备方法,并介绍了L-阿拉伯糖的性质,展望了L-阿拉伯糖生产的发展趋势。     

日开发生产阿拉伯糖的新方法

日本Unitika公司开发了一种酶基方法生产L-阿拉伯糖,这是一种低卡罗里增甜剂,该化合物是由甜菜滤糟和其它残渣纤维(如桔子和苹果纤维)多糖用来自曲霉属霉的阿拉伯酶和阿拉伯呋喃糖酶生产。生产L-阿拉伯糖的通常方法涉及半纤维素的酸基分解,半纤维素是由谷纤维、阿拉伯胶和甜菜浆用碱萃取而得,该法除需专门的反应器外,还需中和化学品和处理碱酸废水的副加处理。新方法,滤糟与水和酶在一容器内在40-80℃混和3-24h,含阿拉伯糖的溶液经过滤,用活性炭和离子交换处理提炼,然后蒸发浓缩,生成L-阿拉伯糖结晶,该新方法已经间歇试验证明,公司现正计…     

L-阿拉伯糖研究进展

综述了L-阿拉伯糖的最新研究进展.内容包括:L-阿拉伯糖的提取及用途、L-阿拉伯糖的传统提取工艺和设备的改进以及L-阿拉伯糖的合成.     

阿拉伯糖催化制取L-核糖的工艺研究

本文对L-阿拉伯糖差相异构反应生成L-核糖进行了实验研究;通过正交试验分析确定了最佳阿拉伯糖转化条件:PH值2.5、反应温度95℃、钼酸铵加入量0.5%、糖液浓度15%,L-阿拉伯糖的转化率达16.9%。     

鸡毛水解液活性炭脱色工艺条件研究

采用活性炭对鸡毛水解液进行脱色处理,考察水解液稀释倍数、活性炭用量、脱色时间和温度等工艺条件对脱色效果以及溶液中L-亮氨酸保留量的影响.结果表明:最佳工艺条件为,将水解液稀释2倍后,在60℃下加入6g/100mL的活性炭,脱色20min.     

L-核糖的生物合成及其在药物中的应用

L-核糖是一种重要的药物中间体。综述了以核糖醇及L-阿拉伯糖为原料的L-核糖的生物合成方法,介绍了L-核糖在L-核苷类药物、糖缀合物、寡核苷酸中的应用进展。     

甘蔗渣水解液替代部分糖源生产细菌纳米纤维素的研究?

以甘蔗渣水解液替代部分糖源,比较研究了四株菌生产细菌纳米纤维素(Bacterial Nanocellulose, BNC)的情况。甘蔗渣水解液含96.5 g/L葡萄糖、35.5 g/L木糖,少量阿拉伯糖、甘露糖和半乳糖,并含有9.2 g/L糠醛、14.0 g/L乙酸,以及少量的5-羟甲基糠醛和甲酸。含体积比15%和10%水解液的培养基对KomagataeibacterxylinusDHU-HL-Z1、DHU-HL-Z2和DHU-HL-Z3生产BNC有促进作用,而ATCC 23770菌株对水解液最不耐受,BNC产量无明显增益。在含10%水解液的培养基中,DHU-HL-Z2和DHU-HL-Z1两个菌株的粗BNC转化率分别为0.61g/g和0.58g/g,显著高于(p<0.05)菌株DHU-HL-Z3和ATCC 23770。     

山羊毛水解液中的氨基酸分析

初步研究确定了山羊毛水解液中多种氨基酸含量的化学分析路线及其相应的分析方法。对小试产品L-胱氨酸进行含量分析,从而确定山羊毛水解液中提取L-胱氨酸的最佳操作条件,为今后产品的工业化生产提供理论依据。     

木薯秸秆木质纤维素的预处理研究

对木薯秸秆稀酸预处理条件进行了优化研究.考察了液固比、反应温度、盐酸体积分数、反应时间对水解液还原糖浓度的影响.结果表明,在液固比为40:1、反应温度为100℃、盐酸体积分数为3%、反应时间为5 h的优化条件下,水解液中还原糖浓度达9.35 g·L-1.     

Determination and correlation of the solubility of L-arabinose and D-galactose in binary solvent mixtures from 278.15 to 333.15 K

L-arabinose and D-galactose could be released during the hydrolysis process of Arabic gum. The development of a crystallization process of L-arabinose is highly dependent on the knowledge of the solubility of both saccharides. In this work, the solubility of L-arabinose and D-galactose in binary mixtures of methanol-water or ethanol-water (mole fraction of water ≤0.5816) was determined at temperatures between 278.15 and 333.15 K by a static equilibrium method. The experimental data correlated well with the modified Apelblat equation, the simplified polynomial empirical equation, NRTL model and UNIQUAC model. Additionally, the thermodynamic properties including the dissolution enthalpy and entropy were obtained from the experimental data. Within the studied temperature range, the dissolution is endothermic and the dissolution process is non-spontaneous.     

Studies on the Interaction of Arabic (Acacia senegal) and Mesquite (Prosopis juliflora) Cum as Emulsion Stabilizing Agents for Spray-Dried Encapsulated Orange Peel Oil

ABSTRACT

The encapsulation properties of pure mesquite and arabic gum powders and mixtures thereof with orange peel oil were measured. The highest rate of encapsulated oil was found to be 93.5 % for a ratio of 60.40% of arabic to mesquite gums. Pure arabic gum preparations were able to encapsulate similar amounts of the oil. Sensory evaluvation of the microencapsulates showed no significant differences (a≤.05) in flavor intensity beween orange peel oil encapsulated with pure arabic gum and mixtures containing mesquite gum.     

Chemical modification of gum arabic and its application in the encapsulation of Cymbopogon citratus essential oil

Sodium trimetaphosphate (STMP) is an effective crosslinking agent of starch and can be used in other polysaccharides for promoting changes in their physical and chemical characteristics. In this study, gum arabic was modified with different STMP concentrations and evaluated as the changes in the physical and physicochemical characteristics. Further, modified gum arabic was evaluated by encapsulation efficiency (EE) of Cymbopogon citratus essential oil. A lower viscosity was observed with the increase of the STMP concentration. Higher concentrations of STMP decreased the water amount retained in the modified gum arabic. The increasing of the crosslinking degree causes a decrease in particle size. The EE of modified gum arabic with 6% STMP was 97%, whereas for the unmodified gum arabic was 85%. The high efficiency encapsulation of the essential oil is a positive result of physicochemical changes in the gum arabic crosslinking. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41519.     

UTILIZATION OF MESQUITE ( Prosopis julijlora) GUM AS EMULSION STABILIZING AGENT FOR SPRAY-DRIED ENCAPSULATED ORANGE PEEL OIL

Abstract

Orange peel oil was microencapsulated. Mesquite gum and its performance for producing spray-dried powders was compared to emulsions prepared with gum arabic. Average oil droplet size of mesquite gum capsules was smaller than that of gum arabic. Emulsions made with mesquite gum showed better stability than those made with gum arabic. Encapsulation capacity of mesquite gum was found to be 80.5 % of the starting oil whereas gum arabic was able to encapsulate 93.5 %. Sensory evaluation showed that there was not significant difference (α<0.05) in flavor intensity between orange peel oil encapsulated with the two emulsifiers.     

Physicochemical Properties of Dry-Heated Peanut Protein Isolate Conjugated with Dextran or Gum Arabic

Peanut protein isolate (PPI) were conjugated with dextran or gum arabic through glycation to study the physiochemical properties of PPI–polysaccharides conjugates. Structural features, solubility as well as emulsifying properties of the two conjugates were compared. The degree of graft value of the two conjugates suggested that glycation of PPI with gum arabic took place more easily than with dextran. Glycated conjugates had better solubility and emulsifying ability than native PPI. Analysis of structural features of the conjugates suggested that their improved functional properties could be the result of less α-helix secondary structure, lower surface hydrophobicity and less compact tertiary structure. The solubility of PPI–dextran conjugates was improved for the pH range 3–9, while that of PPI–gum arabic conjugates was improved above neutral pH range. Moreover, better emulsifying ability was observed in PPI–gum arabic conjugates than PPI–dextran conjugates.     

Screening of different hydrocolloids for improving the quality of fried papad

Papads prepared from cereals, legumes and combinations thereof are India s contribution to the international menu. They are specially relished as snacks in fried form. In the present study hydrocolloids amounting to 0.25‐1.00% of fried papads prepared from black gram were investigated. The hydrocolloids chosen were guar gum, carrageenan, carboxymethyl cellulose, hydroxypropylmethyl cellulose, gum tragacanth, gum karaya, gum ghatti and gum arabic. It was observed that carboxymethyl cellulose was the most effective in increasing the diametrical expansion of the papads at a concentration of 1.00%, while gum arabic at 1.00% caused a maximum reduction in oil content (26.19% as compared to control). Gum tragacanth at 0.5% gave the best texture, measured as crispness using Steven's LFRA texturimeter.     

Comparison of the Efficiency of Five Different Drying Carriers on the Spray Drying of Persimmon Pulp Powders

The aim of this work was to compare the efficiency of different carrier agents (maltodextrin, gum arabic, starch sodium octenyl succinate, whey protein concentrate, and egg albumin) on the powder recovery and physicochemical properties of persimmon powders produced by spray drying. Moisture content, water activity, hygroscopicity, solubility index, total phenol retention, color parameters, particle size, morphology, crystalline state, and sorption isotherms of persimmon powders were determined. No powder was recovered when the persimmon pulp was spray dried alone. The amount of maltodextrin, gum arabic, starch sodium octenyl succinate, whey protein concentrate, and egg albumin needed to obtain a powder recovery of 70% was 45, 30, 30, 25, and 10%, respectively. The use of maltodextrin, gum arabic, and starch sodium octenyl succinate resulted in higher total polyphenol retention and better reconstitution properties, but the powders were paler than those with whey protein concentrate and egg albumin. All carriers could aid the formation of persimmon irregular spherical microcapsules. However, powders produced with maltodextrin and gum arabic had a smoother surface and a more spherical shape than powders produced with other carriers. In addition, powders produced with starch sodium octenyl succinate, whey protein concentrate, and egg albumin were more agglomerated and shriveled compared to those produced with maltodextrin and gum arabic. All experimental data of water adsorption were well fitted to the Guggenheim-Anderson-de Boer (GAB) model.     

Microencapsulation of Cinnamon Oleoresin by Spray Drying Using Different Wall Materials

Microencapsulation of spice oleoresin is a proven technology to provide protection against degradation of sensitive components present therein. The present work reports on the microencapsulation of cinnamon oleoresin by spray drying using binary and ternary blends of gum arabic, maltodextrin, and modified starch as wall materials. The microcapsules were evaluated for the content and stability of volatiles, entrapped and total cinnamaldehyde content for six weeks. A 4:1:1 blend of gum arabic:maltodextrin:modified starch offered a protection, better than gum arabic as seen from the t_1/2; i.e., time required for a constituent to reduce to 50% of its initial value.     

Microencapsulation of Cinnamon Oleoresin by Spray Drying Using Different Wall Materials

Microencapsulation of spice oleoresin is a proven technology to provide protection against degradation of sensitive components present therein. The present work reports on the microencapsulation of cinnamon oleoresin by spray drying using binary and ternary blends of gum arabic, maltodextrin, and modified starch as wall materials. The microcapsules were evaluated for the content and stability of volatiles, entrapped and total cinnamaldehyde content for six weeks. A 4:1:1 blend of gum arabic:maltodextrin:modified starch offered a protection, better than gum arabic as seen from the t_1/2; i.e., time required for a constituent to reduce to 50% of its initial value.