Extraction of polyphenols from white distilled grape pomace: Optimization and modelling
Extraction of polyphenols from white distilled grape pomace: Optimization and modelling
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DOI：
10.1016/j.biortech.2007.02.009
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发表时间：
2008-03-01
影响因子：
11.4
通讯作者：
Nunez, Maria Jose
中科院分区：
文献类型：
--
作者：
Guerrero, M. Sanchez;Torres, J. Sineiro;Nunez, Maria Jose
在立式提取机上对葡萄渣中多酚进行了醇提和水提两种提取工艺。“Albariflo”。实验设计分析了流量（2 ml/min和4 ml/min）和温度（40℃和50℃）的影响。与以往对不同葡萄品种进行分批提取的结果相比，水提法得到的多酚类物质的收率远高于乙醇提取法（最高可达30倍）。采用第二菲克定律对直径为0.5 mm的球形颗粒进行萃取，得到有效扩散系数。还估计了传质系数，得出的结果是，外部传质阻力可以忽略不计。相关系数为0.989 ~ 0.9999。水提法的有效扩散系数值在0.6之间。10(-11) m(2)/s和2.1。10(-11)米(2)/ s。以乙醇为溶剂，有效扩散系数较低，在0.1之间。10(-11) m(2)/s和0.76。10(-11)米(2)/ s。(C) 2007 Elsevier Ltd.版权所有。
Both ethanolic and aqueous extraction were carried out in a laboratory-scale vertical extractor to obtain polyphenols from distilled grape pomace of Vitis vinifera var. "Albariflo". An experimental design was performed to analyse the effects of flow (2 ml/min and 4 ml/min) and temperature (40 degrees C and 50 degrees C). Yields of polyphenolics from aqueous extraction were much higher (up to 30-fold) than those of ethanolic extraction, in contrast with previous results obtained by us from batch extraction of different grape varieties. Polyphenols extraction was modelled by application of second Fick's law to spherical particles of 0.5 mm diameter, so obtaining the effective diffusion coefficient as parameter. The mass transfer coefficients were also estimated, giving as result that the external mass transfer resistance was negligible. Correlation coefficients ranged 0.989-0.9999. Effective diffusivity values in water extraction assays were between 0.6 . 10(-11) m(2)/s and 2.1 . 10(-11) m(2)/s. Using ethanol as solvent, the effective diffusivity was lower, between 0.1 . 10(-11) m(2)/s and 0.76 . 10(-11) m(2)/s. (C) 2007 Elsevier Ltd. All rights reserved.