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石榴花色素的提取及稳定性研究 总被引:1,自引:0,他引:1
以石留花为原料提取石榴花色素,并对影响它提取率的因素:提取剂、提取温度、提取pH值、提取剂用量、提取次数等方面进行大量实验研究,进行分析得出提取石榴花色素的最佳条件为30℃水浴下,pH=1的95%乙醇溶液以1∶8的料液比浸泡1.0 h得到产率较高的色素,从而设计出石榴花色素提取工艺;对色素的耐酸碱性、耐热性、耐光性、耐氧化还原性、及对食品添加剂食盐、蔗糖、柠檬酸等方面进行测定分析得出石榴花色素色泽具有较好的耐光耐热耐还原能力,而对氧化剂适应能力较差,对食品添加剂适应能力较强;最后通过各种金属离子对该色素色泽的影响实验,得出大多数金属离子(除Fe3 、Pb2 )对该色素色泽无影响,从而得出该色素在食品、饮料、糖果及酒类等方面,具有很大的开发应用和前景。 相似文献
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月季花色素的提取及稳定性研究 总被引:3,自引:0,他引:3
以月季花为原料提取月季花色素,并对影响它提取率的因素:提取剂、提取温度、提取pH值、提取剂用量、提取次数等方面进行大量实验研究,进行分析得出提取月季花色素的最佳条件为40℃水浴下,用pH=4.0的95%乙醇溶液以1:10的料液比回流提取1.0h(3—4次)得到产率较高的色素,从而设计出月季花色素提取工艺;对色素的耐酸碱性、耐热性、耐光性、耐氧化、耐还原性、及对食品添加剂食盐、蔗糖、柠檬酸等方面进行测定分析得出:月季花色素具有较好的耐热耐酸碱耐氧化能力,而耐光性及对还原剂适应的能力较差,对食品添加剂适应能力较强;最后通过各种金属离子对该色素色泽的影响实验,得出大多数金属离子(除Fe^3+、Cu^2+、Al^3+)对该色素色泽无影响,从而得出该色素在食品、饮料、糖果及酒类等方面,具有很大的开发应用和前景。 相似文献
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以紫红色四季报春花为原料提取色素,并对该色素的稳定性进行研究。结果表明,适宜的提取溶剂为pH=1的95%乙醇溶液,该色素在382 nm处有最大吸收峰;该色素热稳定性差,有较强的耐光性,耐氧化性,还原性差,在酸性条件下不稳定;金属离子Na+、K+、Mg2+、Zn2+对色素的影响较小,而Fe3+对该色素稳定性的影响较大;常用食品添加剂(葡萄糖、蔗糖、可溶性淀粉和柠檬酸)对该色素色泽无不良影响。 相似文献
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千根草红色素的提取及其稳定性研究 总被引:1,自引:0,他引:1
研究了千根草红色素的提取条件和稳定性。以乙醇作提取剂,用紫外分析法研究色素的稳定性。得到乙醇提取的适宜工艺条件是:以pH=3的65%乙醇溶液,原料与乙醇的质量与体积比为1∶10,在室温下浸提24h。色素在320 nm有最大吸收峰,该色素水溶性较好,在pH值1~9时具有良好的稳定性,热稳定性也良好。蔗糖、葡葡糖和盐等食品添加剂对色素无影响,但淀粉对其影响较大,耐光性较差。影响明显的氧化剂有(NH4)2S2O8、还原剂有抗坏血酸,金属离子对其影响较大。 相似文献
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鸡骨草色素的超声提取及稳定性研究 总被引:1,自引:0,他引:1
采取超声波辅助提取鸡骨草色素的单因素实验和正交试验,确定最佳工艺条件,并研究色素的稳定性。超声提取法的优化工艺条件为:料液比为(g∶mL)1∶50,超声辅助功率140W,提取时间30min,提取温度为70℃,提取剂为50%乙醇。鸡骨草色素对光的稳定性较好;在室温下亦很稳定,温度升高其降解速度加快,对热稳定性较差;食品添加剂对其稳定性影响较小;耐氧化性较好,耐还原性稍差;K+、Na+、Mg2+和Ga2+等离子对色素基本无影响,Fe3+、Zn2+和Cu2+等对其稳定性有一定影响。该方法提取色素缩短了提取时间,更有效、更经济。 相似文献
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用水煮法提取了天然茶叶染料,研究了茶叶色素的吸收光谱。对固液比、提取温度、浸提剂酸度、反应时间等提取条件进行了研究,并测定了色素在不同pH、温度等条件下的稳定性。结果表明,提取茶叶色素的最佳工艺条件为固液比1∶20,在沸煮(100℃)的条件下提取50分钟。该色素受pH影响较明显,对氧化剂、还原剂较敏感,但耐热稳定性较好。金属离子Ca2+、Cu2+、Zn2+、Mg2+、Na+、K+、Pb2+、Sn2+、Ni2+的存在对色素色泽基本无影响,Al3+、Fe2+、Fe3+的存在对色素有不良影响。茶叶色素易溶于水、乙醇、低浓度乙酸等极性溶液,不溶于苯、丙酮、氯仿、乙醚等非极性溶剂,属水溶性色素。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献