Fernández-Bolaños Juan, Rodríguez Guillermo, Rodríguez Rocio, Heredia Antonia, Guillén Rafael, Jiménez Ana
Food Biotechnology Departament, Instituto de la Grasa (CSIC), Avenida Padre García Tejero 4, Apartado 1078, 41012 Sevilla, Spain.
J Agric Food Chem. 2002 Nov 6;50(23):6804-11. doi: 10.1021/jf011712r.
The effect of hydrothermal treatment of two-phase olive waste (alperujo) on the solubilization of hydroxytyrosol was studied. Different conditions of saturated steam were assayed. A high amount of hydroxytyrosol was solubilized and increased with increasing steaming temperature and time, reaching 1.4-1.7 g/100 g of dry alperujo. The effect of acidic (H(2)SO(4)) and basic (NaOH) catalysts was also evaluated. Acid-catalyzed treatment was more effective at milder conditions, whereas the alkali-catalyzed conditions were not very suitable. In the present study, the extracted hydroxytyrosol was purified by means of a new, simple, and inexpensive chromatographic system, under international patent application (PCT/ES02/00058). From 1000 kg of alperujo, with 70% humidity, can be obtained approximately 4.5-5 kg of hydroxytyrosol. After a purification process, at least 3 kg of hydroxytyrosol, at 90-95% purity, would be obtained. The purified compound was identified by HPLC/UV and (1)H and (13)C NMR analyses, and its antioxidant activity was tested on refined olive oil without antioxidants by Rancimat method. The oxidative stability of refined olive oil was increased by a factor of 1.71 in the presence of 100 ppm of hydroxytyrosol.
研究了两相橄榄果渣（alperujo）水热处理对羟基酪醇增溶的影响。测定了不同饱和蒸汽条件。大量的羟基酪醇被增溶，且随着蒸汽温度和时间的增加而增加，达到1.4 - 1.7克/100克干alperujo。还评估了酸性（H₂SO₄）和碱性（NaOH）催化剂的效果。酸催化处理在较温和条件下更有效，而碱催化条件不太合适。在本研究中，提取的羟基酪醇通过一种新的、简单且廉价的色谱系统进行纯化，该系统正在申请国际专利（PCT/ES02/00058）。从1000千克湿度为70%的alperujo中，大约可获得4.5 - 5千克羟基酪醇。经过纯化过程后，将获得至少3千克纯度为90 - 95%的羟基酪醇。通过HPLC/UV以及¹H和¹³C NMR分析对纯化后的化合物进行了鉴定，并通过Rancimat法在不含抗氧化剂的精炼橄榄油上测试了其抗氧化活性。在存在100 ppm羟基酪醇的情况下，精炼橄榄油的氧化稳定性提高了1.71倍。
