谷物中戊聚糖含量测定方法的比较研究

分别用气相色谱法、地衣酚-盐酸法、间苯三酚-冰醋酸法以及Duffau蒸馏法对小麦戊聚糖含量进行了测定.在研究过程中以气相色谱法为标准,就地衣酚-盐酸法、间苯三酚-冰醋酸法以及Duffau蒸馏法与气相色谱法之间的相关性进行研究,通过研究得到测定谷物中戊聚糖含量的最佳方法,即采用间苯三酚-冰醋酸比色法.研究发现间苯三酚-冰醋酸法与气相色谱法具有较好的相关性,并且该方法测定较快速、准确.     

马尾松回用纤维品质衰变规律及其机理研究

通过对马尾松亚硫酸盐浆、TMP浆和GWP浆的回用实验,本文得出了回用纤维品质衰变的基本规律。根据著名的Page方程,从回用纤维中聚戊糖含量的变化和回用纤维长度分布的变化以及回用纤维纸页光散射系数变化等数据中推断出了影响回用纤维品质衰变的主要因素,并进一步探讨了这些因素影响回用纤维品质的机理。     

Effects of genotype and harvest year on content and composition of dietary fibre in rye (Secale cereale L) grain

The aim of this study was to measure the variation in dietary fibre (DF) content and composition among different rye varieties grown in the same location in three successive years and to estimate the contributions of genotype and harvest year to this variation. The study included grain from 19 different varieties of rye, of which seven varieties were analysed in all three years. The content of total DF in all samples ranged from 147 to 209 g kg^?1 dry matter (dm), with 34–66 g kg^?1 being water‐extractable (WE) DF and 108–159 g kg^?1 being water‐unextractable (WUE) DF. The main DF component was arabinoxylan (AX) with a content of 80–121 g kg^?1 dm, of which 26–41 g kg^?1 dm was WE AX. The ratio of arabinose to xylose (ara/xyl) of total AX ranged from 0.59 to 0.69. The content of β‐glucan was 13–22 g kg^?1 dm and that of fructan was 45–64 g kg^?1 dm. Analysis of the data from seven varieties and three harvest years showed a highly significant influence of harvest year on most DF components. Significant genotype effects were found for the contents of total DF, total AX, β‐glucan and fructan and for the ara/xyl ratio of total and WUE AX. Estimation of variance components showed that yearly variations in the contents of total DF, total AX, WUE DF, WUE AX and β‐glucan were generally higher (27–55% of total variance) than genotype effects (14–19%). The ara/xyl ratio of total and WUE AX showed a high influence of genotype (46 and 43% respectively). Non‐adapted rye varieties with small kernel size had the highest contents of total DF and total AX. The content of β‐glucan was positively correlated with kernel weight (r = 0.68), whereas no overall correlation was found between kernel size and the content of DF. As a conclusion, the variation in DF content and composition in this study was significantly influenced by both harvest year and rye genotype. © 2002 Society of Chemical Industry     

小麦麸皮戊聚糖的润肠通便效果研究

对小麦麸皮不同组分的润肠通便效果进行研究,发现小麦麸皮碱溶戊聚糖组分(AEP)具有较好的润肠通便效果,而水溶戊聚糖组分(WSP)和剩余麸皮残渣(AEP-R)的润肠通便效果较差.这说明小麦麸皮中起润肠通便作用的是其中的戊聚糖组分,并且戊聚糖的润肠通便效果与其溶解性有关,溶解性较差的组分具有较好的润肠通便效果,水溶性较好的组分润肠通便效果较差.     

小麦麸皮中戊聚糖的制备、分级及组成分析

采用小麦麸皮为原料 ,分别用水和碱为提取溶剂制备水溶戊聚糖和水不溶戊聚糖 ,然后用溶剂沉淀和离子交换柱层析两种方法对所制备的戊聚糖进行分级纯化 ,并对各分级组分的组成进行了分析     

Changes in β-glucan and other carbohydrate components of barley during malting

Changes in total (1→3), (1→4)-β-glucan content were followed during the micro-malting of nine varieties of barley with a wide range of malting qualities. These changes were related to estimates of endosperm modification based upon staining with Calcofluor. β-Glucan content declined from an average of 3.54% in the barley to 0.75% in the malt. Pentosan and total starch (including starch-derived oligosaccharides) levels showed comparatively little change during malting. β-Glucan composition of the barley was a poor indicator of malting performance. However, the β-glucan, starch and xylose contents of the malt all showed significant correlations with malt extract. Estimation of malt β-glucan content gave the best indication of malt quality. Direct determination of β-glucan may be of more value in assessing malt quality than indirect techniques based upon assessing modification of stained grains.     

黑小麦面粉戊聚糖的制备与理化性质分析

以黑小麦面粉为原料,分别采用水和Ba（OH）2溶液作为介质,提取黑小麦面粉中的水溶性戊聚糖（WEAX）和碱溶性戊聚糖（WUAX）,运用离子色谱、高效液相色谱和红外光谱等对黑小麦面粉戊聚糖的理化性质进行分析．结果表明：WEAX的单糖组成主要为阿拉伯糖（Ara）和木糖（Xyl）,并含有少量半乳糖（Gal）,摩尔比Ara：Xyl：Gal ＝5．74：11．64：1,其取代度A／X为0．49,相对分子质量Mw为7．73×105;WUAX的单糖组成主要为Ara和Xyl,摩尔比Ara：Xyl ＝1：1．74,其A／X为0．57,Mw为6．56×104,表明WEAX的分支程度低于WUAX,但其Mw高于WUAX;红外光谱表明两种戊聚糖均存在糖类的特征吸收峰．     

利用竹纤维制备过程中产生的聚戊糖制备糠醛的研究

以竹纤维制备过程中产生的聚戊糖为原料,制备重要化工原料——糠醛。研究结果表明,在常用的催化剂中,硫酸为较佳选择。由单因素实验得出的最佳工艺条件为:以3g竹纤维废液为原料,5%(wt)的硫酸溶液为催化剂,在160℃下蒸馏4h时,糠醛收率达到最大值92.4%。     

地衣酚——盐酸法测定燕麦β葡聚糖中的戊聚糖含量

目前国内外对从植物提取葡聚糖和戊聚糖的方法较为相似。文章以地衣酚——盐酸法为基础,根据己糖与戊糖混合体系的反应液在吸收光谱670 nm与580 nm处存在最大差谱,进行燕麦β-葡聚糖中戊聚糖的测定。通过精确度和回收率试验验证了该方法进行可行性。     

小麦麸皮戊聚糖氧化胶凝机理研究

采用凝胶过滤色谱(Sepharose CL-4B)和紫外吸收光谱,以小麦麸皮戊聚糖组分P-WSPI和P-WSPII为例,对戊聚糖的氧化胶凝机理进行了研究.研究表明,戊聚糖的氧化胶凝反应是由其主要组分阿拉伯糖与木糖组成的复合物(P-WSPI)所引起,其中含有的阿魏酸基团参与戊聚糖的氧化胶凝反应,并使戊聚糖相对分子质量变大,进而使溶液粘度增加;而阿拉伯糖与半乳糖组成的复合物(P-WSPII)因不含有阿魏酸,没有发生氧化胶凝反应.