橡子单宁脱除技术研究

对橡子中单宁的脱除技术进行了实验研究。实验结果表明:超声波助提较微波助提和常规水浸提效果明显。通过正交实验得出超声波助提脱除单宁的最佳条件为:料水比1:30g/mL,温度45℃,时间40min,超声波功率和频率分别为454W和47.6kHz。      

橡子单宁脱除技术研究

对橡子中单宁的脱除技术进行了实验研究.实验结果表明:超声波助提较微波助提和常规水浸提效果明显.通过正交实验得出超声波助提脱除单宁的最佳条件为:料水比1:30g/mL,温度45℃,时间40min,超声波功率和频率分别为454W和47.6kHz.     

蒙古栎橡子中单宁的脱除工艺

研究超声波脱除蒙古栎橡子中单宁的工艺。通过单因素试验选择对单宁脱除效果影响较大的因素进行正交试验,确定的最佳脱除条件为乙醇溶液体积分数40%、料液比1:30(g/mL)、颗粒度80目以上、超声温度55℃、超声功率400W、超声时间60min。在此条件下可以使单宁脱除量达到69.99mg/g。     

麻栎橡子单宁脱除工艺优化及抗氧化性

为探索高效可行的麻栎橡子单宁脱除工艺,实现其综合开发,以桥山林区麻栎橡子为原料,采用超声辅助乙醇法对影响单宁脱除率的因素进行单因素试验,选择影响显著的4个因素进行响应面分析,并测定单宁对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和羟自由基(·OH)的清除率,以探索麻栎橡子单宁的抗氧化活性。结果表明,液料比、乙醇体积分数、脱除温度、超声功率对单宁脱除率影响显著,模型拟合效果显著。最优脱除工艺为液料比42∶1(mL/g)、乙醇体积分数53%、脱除温度65℃、超声功率240 W,单宁脱除率为37.27%。麻栎橡子单宁抗氧化性与其质量浓度呈线性正相关,质量浓度为80 mg/L时,其对DPPH自由基的清除率可达75.56%,对·OH的清除率可达62.74%,可作为新型抗氧化剂。     

冷榨核桃油饼单宁脱除技术研究

为开发利用冷榨核桃油饼中优质蛋白,采用响应面分析法优化冷榨核桃油饼中单宁脱除的工艺条件。试验结果表明:在料水比1∶25(g∶m L),p H 7,55℃条件下浸泡150 min,单宁脱除率为50.44%,蛋白损失率为2.97%;重复浸泡30 min,其他条件不变,冷榨核桃油饼二次单宁脱除率为75.44%,蛋白损失率为4.57%。采用此方法冷榨核桃油饼中单宁脱除率较高,蛋白损失率较低。经粉碎或磨浆过滤喷雾干燥后可生产优质蛋白质粉。     

果汁中单宁脱除方法的研究进展

单宁是广泛存在于蔬菜和水果中的植物多酚,果汁生产中单宁会影响其口感、色泽和澄清度,因此,果汁生产中单宁的脱除对果汁产品质量的提高具有重要的作用。本文综述了果汁生产中单宁脱除方法(物理脱除法、化学脱除法、生物脱除法和其他方法) 的机理、优缺点、应用研究现状及前景。     

橡子单宁的提取优化及其在皮革中的应用

优化了从橡子中提取单宁的最佳工艺参数,并考察其鞣制性能。研究了溶剂/原料比(20~100mL/g)、时间(2~10h)和混合溶剂比(甲醇-水)(0~100%)对提取率、单宁含量和单宁总量的影响。将最佳优化条件下提取出的橡椀单宁应用于皮革鞣制中,并测定鞣革的填充系数(%)和收缩温度(Ts)。优化的提取参数如下:溶剂/原料比为100mL/g,提取时间为6h,混合溶剂比为62%甲醇-38%水。采用提取出的单宁鞣后成革的填充系数为57.81%,收缩温度为75.5℃,远好于市售橡椀单宁鞣革(52.83%,73℃),凸显出优化过程的重要性。表明使用提取出的橡椀单宁作为植物鞣剂应用于皮革工业中,鞣制效果令人满意。     

橡子淀粉制备及其理化性质研究

以橡子粉为原料,制备橡子淀粉以及研究橡子淀粉的理化性质。采用热水脱单宁、H2O2脱色制备橡子淀粉,运用理化检测方法对橡子淀粉的理化性质进行研究。研究表明,橡子粉中淀粉含量为63.58%;橡子淀粉的溶解度和膨胀度都不大,膨胀度随温度的上升出现初始膨胀阶段和迅速膨胀阶段,属限制型膨胀淀粉;橡子淀粉糊的透光率和冻融稳定性相对较好,淀粉糊的透光率为35.9%,析水率为34.69%;橡子淀粉糊具有很强的凝沉稳定性,但凝沉速度较快,易老化;橡子淀粉的黏度随浓度的增加而增加,出现跃变的浓度为25%。     

橡子壳色素提取技术研究

为了提高橡子资源综合利用程度,对橡子壳色素提取技术进行了实验研究。通过单因素试验和正交试验L9(34)确定了橡子壳色素提取的最适条件。单因素试验结果表明,提取橡子壳色素的适宜条件是:提取剂为45%乙醇,料液比为1:40(g/mL),提取温度为80℃,时间为5h。用非极性溶剂(如石油醚)处理橡子壳粗粉可提高色素提取效果。正交试验结果表明,提取橡子壳色素的最适条件组合是:提取剂为40%乙醇,料液比为1:50(g/mL),温度为70℃,时间为5h。所得橡子壳色素是一种由多种成分组成的红褐色粉末。此外,对橡子壳色素紫外—可见分光光度法检测的工作波长进行了研究,结果表明,在390nm处,色素浓度与吸光值具有良好线性关系,回归方程为y=3.25226x+0.01288(r=0.99955),故选用390nm作为检测工作波长。     

肉桂单宁的提取工艺比较研究

进行了溶剂法和超声辅助法提取肉桂单宁的工艺研究,采用了儿茶素为标准品,香草醛-硫酸为显色剂的分光光度法定量分析肉桂单宁含量。结果表明,儿茶素浓度(C)与吸光度(A)在0.05~0.30mg/mL浓度范围内呈线性关系,方程为:Y=3.0153X+0.0050。溶剂法提取的优化工艺为:乙醇体积分数60%,料液比1∶30g/mL,提取时间150min,提取温度70℃,单宁得率为42.35mg/g。超声辅助法最佳工艺为:乙醇体积分数50%,料液比1∶20g/mL,超声功率360W,提取时间40min,提取温度40℃,单宁得率为41.28mg/g。与溶剂法相比,超声辅助法显著减少了溶剂用量,降低了提取温度,缩短了提取时间。     

噬菌体制剂中内毒素脱除方法的比较研究

目的 建立动态浊度法检测噬菌体制剂中内毒素含量, 并探索不同方法对制剂中内毒素的脱除效果。方法 采用动态浊度法检测噬菌体制剂中内毒素含量, 然后采用凝胶层析、超滤及活性炭吸附法对噬菌体制剂进行处理, 检测处理前后噬菌体制剂中内毒素含量及噬菌体效价的变化。结果 基于动态浊度法,建立了内毒素标准曲线回归方程lgT=-0.2732 lgC+3.149, 其线性浓度范围为0.05-10.0 EU/mL,相关系数│r│=0.9986, 满足可靠性分析要求;凝胶层析、超滤法和活性炭吸附法均能有效脱除噬菌体制剂中的内毒素, 脱除率分别为92.6%, 97.1%和99.1%, 但活性炭吸附法选择性差, 噬菌体效价显著降低。结论 动态浊度法能灵敏检测噬菌体制剂中的内毒素含量,凝胶层析和超滤法可作为噬菌体制剂内毒素脱除的可行策略。     

Selective removal of tannins from medicinal plant extracts using a collagen fiber adsorbent

A novel adsorbent, used for the selective removal of tannins from medicinal plant extracts, was prepared from bovine skin collagen fiber. Some typical active constituents of medicinal plants were selected as probe molecules to investigate the adsorption selectivity of the collagen fiber adsorbent to tannins. In batch adsorption experiments, the extent of adsorption of condensed tannins, including larch tannin, black wattle tannin and bayberry tannin, was 100%. The extent of adsorption of tannic acid and the hydrolyzable tannins was also 100%. In contrast, for the most active constituents of medicinal plants, their amounts adsorbed by collagen fiber adsorbent were limited. For procyanidin, the common active constituents in medicinal plant extracts, its extent of adsorption was also low, although it has a similar basic structure to condensed tannins. In comparison with traditionally used polyamide adsorbent, the collagen fiber adsorbent exhibited an obvious advantage in adsorption selectivity over tannins. Therefore, this study provides a novel and effective method for selective removal of tannins from medicinal plant extracts. Copyright © 2005 Society of Chemical Industry     

Fingerprint of enological tannins by multiple techniques approach

In this study, six enological tannins (T1–T6) from different source were analysed by selected analytical techniques, including UV–Vis, FTIR, NMR, SEC, LC-MS/MS and electronic nose. Moreover, the samples were tested for their antioxidant activity. Spectra and chromatograms are considered as a fingerprint with a pattern that is distinctive for a given type of sample. In particular, tannins showed the maximum UV–Vis absorbance (λ_max) at 273–280 nm, the inflection point (λ_min) at 247–264 nm, and the ratio λ_max/λ_min was 1.03, 1.35, 1.67, 1.36, 2.15, 2.02 for tannin T1–T6, respectively. The FTIR analysis of tannins showed the presence of most important absorption bands at 1522, 1453, 1380, 1350, 1328, 1286, 1210, 1148 and 1044 cm⁻¹. Besides, SEC and NMR analysis allowed to sort the tannins according to their average DP as follows: T1 > T2 = T4 > T3 > T6 = T5. Based on this multiple techniques approach three condensed tannins (sample T3, T5 and T6) were clearly identified, together with two mixtures of hydrolysable tannins (sample T1 and T2), whereas one sample (T4) showed a peculiar pattern different from the commercial tannin commonly used in enology.     

Comparative study of three legume starches

Starch content of chickpea ( Cicer arietinum ), pigeon pea ( Cajanus cajan ) and bonavist bean ( Dolichos lablab ) was 58,52 and 50% respectively with recovery of 57.9, 48.1 and 49.0%. The amylose content was 33.5, 27.0 and 31.0%; amylose chain length was 1420,550 and 830 glucose units and amylopectin chain length was 29, 27 and 28 glucose units for chickpea, pigeon pea and bonavist bean respectively. Chickpea starch granules ranged from large oval shaped (21 × 30 pm) to small spherical (13 pm in diameter); pigeon pea from (35 × 42 pm) to 15.2 pm and bonavist bean (35 × 42 pm) to 15.2 pm. The gelatin-ization temperature range was 67–76°C for chickpea, 71–78°C for pigeon pea and 78–80°C for bonavist bean starch. The swelling power for chickpea, pigeon pea and bonavist bean at 95°C were 17, 18.5 and 22.5% respectively. The legumes showed a single-stage and somewhat restricted swelling. Solubility curves for legume starches showed a similar pattern and indicated that they have higher solubility at elevated temperatures than wheat starch. The liquefaction characteristics showed that chickpea has the highest resistance to cooking and was the most sensitive to a-amylase. The three legume starches gave stabilized Brabender hot-paste viscosity; chickpea had a lower overall viscosity due to its exceptionally long amylose chains.     

3种鱼糜蛋白质特性及油炸特性比较

目的：探究3种鱼糜的蛋白质特性及其油炸特性。方法：以草鱼、鲢鱼和巴沙鱼为原料,通过测定孔隙率、硬度和吸水性等指标表征鱼糜的油炸特性,测定鱼糜的动态流变学性质、泡沫稳定性和SDS-PAGE探究其影响机制。结果：相较于草鱼鱼丸和鲢鱼鱼丸,巴沙鱼鱼丸组织疏松,孔洞大,孔隙率最高,且硬度最低,吸水率最高。巴沙鱼鱼糜的凝胶强度远大于鲢鱼鱼糜和草鱼鱼糜,且草鱼、鲢鱼和巴沙鱼鱼糜的泡沫稳定性分别为63.0%,27.7%,82.0%。SDS-PAGE凝胶电泳结果表明巴沙鱼鱼糜的肌动蛋白和肌球蛋白含量较高。结论：巴沙鱼鱼糜含有较高的肌动蛋白和肌球蛋白,是提高鱼糜凝胶强度和泡沫稳定性的关键因素之一,最终影响鱼糜的油炸特性。     

调质后饲料水分的3种测定方法比较研究

探求便于实际生产中应用的调质后物料水分测定方法。采用冷晾减重法、一次性密封法和铝盒法测定了不同企业、不同调质器出口的调质后物料水分,并对测定结果进行了比较。结果表明:冷晾减重法和一次性密封法测定的水分值之间无显著性差异(P>0.05);采用铝盒法测定的水分值和其他两种方法测定的水分值相比,明显偏低(P<0.05)。     

鲢鱼CPIs的三种电泳鉴定方法的比较研究

本文对Geltain-substrate-SDS-PAGE反相酶谱法（方法 A）、Native-PAGE反相酶谱法（方法 B）和与papain反应后进行SDS-PAGE法（方法 C）三种电泳方法的鉴定效果、灵敏度进行了对比,确定了鲢鱼卵粗提样中小分子CPIs的最适电泳鉴定方法。结果表明,对于在电泳上活性不稳定的鲢鱼卵小分子CPIs而言,方法 A灵敏度较低,且可能出现假阳性现象;方法 B虽能准确鉴定小分子CPIs的存在,但不能判断分子量。方法 C,即小分子CPIs与papain在37℃下反应5h以上,然后进行SDS-PAGE,抑制剂条带清晰可见,鉴定效果好,且能提供分子量分布信息。此外,尽管荧光底物法和Azocasein法都无法检测到鲢鱼肝胰浓缩粗提液中半胱氨酸蛋白酶抑制活性,但是利用C法,则有效地鉴定了其中CPIs的存在和分子量分布情况。综上所述,方法 C或协同方法 B的电泳鉴定方法,适用于鲢鱼下脚料粗提样品中CPIs的鉴定,效果理想,灵敏度高,操作简便。      

Comparative study of degumming of silk varieties by different techniques

Different varieties of silk differ from each other in their chemical composition as well as the physical, chemical and mechanical properties. Silk degumming is a primary important process, which needs to be carried out uniformly to a sufficient level to get good quality in further processes such as dyeing. In the present study, we have compared the efficiencies of five different degumming treatments for eri, tasar and mulberry silk fabrics using conventional, ultrasonic and microwave techniques. Among the various treatments, soda ash plus hydrogen peroxide and enzyme (papain) degumming recipies gave the best results in terms of weight loss and absorbency. As compared to the conventional technique, the treatments under ultrasonication and microwave enhanced the efficiency. The microwave technique was found to be superior, with the advantage of drastic reduction in treatment time, better retention of tensile strength and smooth appearance of silk. The dye uptake also increased after degumming. The molecular conformation of the different silk varieties, as estimated by FTIR spectroscopy, and the crystalline structure, as elucidated by X-ray diffraction, remained unchanged. SEM showed distinct morphological changes on degumming.