Brenes M, García A, García P, Garrido A
Food Biotechnology Department, Instituto de la Grasa, CSIC, Avenida Padre García Tejero 4, 41012 Sevilla, Spain.
J Agric Food Chem. 2000 Nov;48(11):5178-83. doi: 10.1021/jf000686e.
Extraction methods to determine olive oil phenols are not exhaustive. A procedure to test their effectiveness, based on the treatment of the extracted oil with 2 N HCl followed by analysis of phenols in the aqueous phase, has been developed. It was concluded, using this test, that 15-40% of phenols remained unextracted when the liquid/liquid extraction method with 80% methanol was applied. Solid phase extraction (C(18) cartridge) succeeded in retaining most of the phenols in the cartridge, but the recovery yield from the sorbent material was low. However, a new extraction method, based on the use of N,N-dimethylformamide (DMF) as an extraction solvent, achieved a complete extraction of phenols from oils. The proposed method requires a lower amount of oil, solvents, energy, and labor than the traditional ones. Because of the low concentration of phenols in the DMF extract, the highly sensitive electrochemical detector (EC) technique was studied. All of the phenols detected by the traditional UV detectors were also detected by EC using a coulometric array system. A rapid and complete analytical methodology of phenols in olive oil has been proposed based on coupling DMF extraction and EC detection.
用于测定橄榄油酚类物质的提取方法并不完善。已开发出一种基于用2N盐酸处理提取的油，然后分析水相中酚类物质来测试其有效性的程序。使用该测试得出的结论是，当采用80%甲醇的液液萃取方法时，15%-40%的酚类物质仍未被提取出来。固相萃取（C(18)柱）成功地将大部分酚类物质保留在柱中，但从吸附剂材料中的回收率较低。然而，一种基于使用N,N-二甲基甲酰胺（DMF）作为萃取溶剂的新萃取方法实现了从油中完全提取酚类物质。与传统方法相比，该方法所需的油量、溶剂量、能量和劳动力更少。由于DMF提取物中酚类物质的浓度较低，因此研究了高灵敏度的电化学检测器（EC）技术。传统紫外检测器检测到的所有酚类物质也都能用库仑阵列系统通过EC检测到。基于DMF萃取和EC检测的联用，提出了一种快速且完整的橄榄油中酚类物质分析方法。
