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不溶性氧化淀粉黄原酸酯的制备 总被引:1,自引:0,他引:1
以玉米淀粉为原料,环氧氯丙烷为交联剂,二硫化碳为酯化剂,过氧化氢为氧化剂,制备了不溶性氧化淀粉黄原酸酯(IOSX)。研究了pH、氧化剂用量、反应温度和反应时间对IOSX羧基含量和硫含量的影响。通过正交试验得出酯化反应条件为:二硫化碳用量31.5%,氢氧化钠用量20%,反应时间2.5 h,反应温度35℃;单因素试验得出氧化反应条件为:pH 9,氧化剂用量14%,反应时间2 h,反应温度35℃。在较佳反应条件下,IOSX羧基含量为0.345%,硫含量为6.34%。 相似文献
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淀粉黄原酸酯是一种金属络合剂,广泛应用于去除水环境体系中的重金属,主要分为水不溶性淀粉黄原酸酯(ISX)和水溶性淀粉黄原酸酯(SSX)两大类,本文着重综述了淀粉黄原酸酯的研究进展及其在水处理中的应用,介绍了国内外应用SSX和ISX处理污水中重金属的现状。 相似文献
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以淀粉为原料,环氧氯丙烷为交联剂,二硫化碳为酯化剂,制备不溶性交联淀粉黄原酸酯。结果表明交联淀粉的最佳操作工艺条件为:玉米淀粉20 g、0.2 g/m L Na OH溶液5.0 m L、环氧氯丙烷4.0 m L、反应温度30℃、反应时间2.5 h。交联淀粉黄原酸酯的最佳合成工艺条件为:交联淀粉10 g,0.2 g/m L的Na OH溶液20 m L,5 m L CS2,温度50℃,反应时间1.0 h。交联淀粉黄原酸酯净化生活废水试验结果表明:在10 m L生活废水中,投加0.7 g淀粉黄原酸酯时,废水吸光度达到最小;当其他条件一定时,生活废水p H约为7、反应时间为40 min时,吸附效果较佳。 相似文献
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测定了木薯淀粉、木薯羟丙基淀粉、羟丙基交联淀粉、醋酸酯淀粉、醋酸酯交联淀粉的冻融稳定性、透光率、凝沉、耐盐性、耐酸性、糊化特性等性质。实验结果表明:经过变性的木薯淀粉和原木薯淀粉有很大的不同,经过羟丙基化、羟丙基交联、醋酸酯化、醋酸酯交联后,分别引入了羟丙基、交联键、乙酰基等,使其具有较强的冻融稳定性,具有较高的透明度、耐盐性、耐酸性。据RVA分析,各种变性淀粉糊液性质较原淀粉有较大的提高。经过交联后糊液稳定性较原淀粉、羟丙基及醋酸酯淀粉有较大程度的提高,因此具有更为广阔的应用性。 相似文献
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木薯淀粉与黄原胶共混干热改性研究 总被引:2,自引:0,他引:2
研究了干热反应的温度、时间及共混物pH对木薯淀粉及黄原胶共混物的影响,对改性产物的交联度、淀粉糊粘度及透明度进行测定,用X-射线衍射仪(XRD)对淀粉结构进行分析。结果表明,干热处理能有效抑制淀粉糊化,降低透明度,证明木薯淀粉和黄原胶发生了交联反应,且淀粉与黄原胶在碱性条件下混合有利于交联反应的进行,交联程度随反应温度和时间的增加而增加。 相似文献
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研究了干热反应的温度、时间及共混物pH对木薯淀粉及黄原胶共混物的影响,对改性产物的交联度、淀粉糊粘度及透明度进行测定,用X-射线衍射仪(XRD)对淀粉结构进行分析。结果表明,干热处理能有效抑制淀粉糊化,降低透明度,证明木薯淀粉和黄原胶发生了交联反应,且淀粉与黄原胶在碱性条件下混合有利于交联反应的进行,交联程度随反应温度和时间的增加而增加。 相似文献
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本文分别制备水相戊二酸木薯淀粉酯(AGAC)和醇相戊二酸木薯淀粉酯(EGAC),使用FT-IR、XRD和SEM进行微观表征,研究两种酯化淀粉的粘度、透明度、流变性、冻融稳定性和抗盐性等理化性质。微观表征的结果显示两种酯化淀粉分子中成功接入了戊二酸基团,两者的晶型均没有发生变化,其整体结构没有受到很大影响,布拉班德粘度仪分析结果表明AGAC的峰值粘度有所提高,同时糊化温度明显降低,EGAC的糊化温度降低,峰值粘度大幅度提高,但粘度稳定性没有提高。AGAC糊液和EGAC糊液的透明度、冻融稳定性和抗剪切力均强于原淀粉,而AGAC和EGAC抗盐性均低于原淀粉,即其热糊稳定性和抗盐性未得到改善。EGAC的透明度高于原淀粉,但低于AGAC;而冻融稳定性、抗剪切能力均略优于AGAC和原木薯淀粉,引入戊二酸基团后,木薯淀粉的透明度、冻融稳定性和抗剪切能力有一定程度的提高。 相似文献
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采用交联―酯化―预糊化复合变性制备乌冬面专用改性淀粉,并与木薯原淀粉、交联淀粉及交联―酯化淀粉进行比较。结果表明,交联淀粉偏光显微及颗粒形貌没发生明显变化,交联变性并未破坏淀粉结晶结构;交联―酯化淀粉颗粒出现粘连和聚集现象,部分颗粒表面出现凹陷和裂纹现象;红外光谱表明,交联―酯化―预糊化复合变性淀粉在1 728 cm–1、1 247 cm–1附近出现新的吸收峰,分子内引入乙酰基团,X–射线衍射光谱显示,交联―酯化―预糊化复合变性淀粉在5.6°和22°处衍射峰强度减弱,A型特征峰加强,结晶类型由"C"型向"A"型转变;交联―酯化淀粉经预糊化处理后,淀粉颗粒膨胀破裂,结晶结构受到彻底破坏,淀粉偏光十字消失,但预糊化处理未破坏淀粉分子化学键。 相似文献
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Varangkana Sanguanpong Sunee Chotineeranat Kuakoon Piyachomkwan Christopher G Oates Pavinee Chinachoti Klanarong Sriroth 《Journal of the science of food and agriculture》2003,83(8):760-768
Acid and enzyme hydrolyses followed by ball milling were applied to fracture cassava starch granules. Microscopic and chromatographic evidence suggested different mechanisms of the two hydrolyses. Using the enzyme process, granules with a sponge‐like structure and shells with the interior hydrolysed were produced. Amylose and amylopectin were subjected equally to multiple attacks by enzymes, with no significant change in granule crystallinity. The hydrolysed residues could not be effectively broken down by ball milling, although the crystallinity was destroyed. In contrast, the acid treatment caused superficial external corrosion, mainly at the amorphous lamellae, ie the branch points of amylopectin. Acid‐lintnerised starch granules were mostly of Degree of polymerization, DP 10–15 and exhibited increased crystallinity and brittleness, making them more susceptible to breakdown upon milling. Ball milling, although destroying some degree of crystallinity, could effectively reduce the size of acid‐hydrolysed starch, with no further degradation of amylodextrin molecules. By a combination of lintnerisation and ball milling, smaller particle starch (3–8 µm compared with 3–30 µm for native starch) could be produced. It is clear that removal of the amorphous phase prior to milling is critical for effective rupture of the granules. Copyright © 2003 Society of Chemical Industry 相似文献
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Manuel Plata-Oviedo Celina Camargo 《Journal of the science of food and agriculture》1998,77(1):103-108
The effects of acid treatments (HCl or organic acids) and drying processes (oven or sun) on the physico-chemical and functional properties of cassava starch have been studied. The objective was to obtain modified starches with expansion properties similar to those of sun dried fermented cassava starch (polvilho azedo) as produced by an empirical process. Expansion was evaluated using a baking test. Independent of the drying method, organic acid-hydrolysed cassava starch presented the same X-ray diffraction patterns (changes from C to A) and similar intrinsic viscosity values. SEM observations showed no differences between granule surfaces of sun dried and oven dried samples. However sun dried organic acid-hydrolysed starches presented lower paste consistency values at 30°C when compared with oven dried ones. HCl-modified cassava starches were oven or sun dried, giving biscuits with low specific volumes (2·5–3·1 ml g−1). Similar behaviour was obtained using oven dried organic acid modified cassava starches. When submitted to sun drying, organic acid modified starches showed great improvements in biscuit expansion (5–10 ml g−1). The highest average specific volumes were obtained using lactic acid modified starches. © 1998 SCI. 相似文献