Departamento de Química e Bioquímica, Centro de Investigação em Química (CIQ-UP), Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal.
J Agric Food Chem. 2012 Jul 25;60(29):7318-25. doi: 10.1021/jf301998s. Epub 2012 Jul 13.
We employed a kinetic method to determine the distributions of the antioxidants hydroxytyrosol (HT) and hydroxytyrosol acetate (HTA) between the oil, aqueous, and interfacial regions of a model food emulsion composed of stripped olive oil, acidic water, and a blend of Tween 80 and Span 80 [hydrophilic–lipophilic balance (HLB) = 8.05] as an emulsifier. HT is oil-insoluble, but HTA is both oil- and water-soluble (partition constant P(O)(W) = 0.61). Results indicate that, at a given emulsifier volume fraction Φ(I), the fraction of HTA in the interfacial region is higher than that of HT. The percentage of both antioxidants increases with an increasing Φ(I), so that % HT > 40% at Φ(I) = 0.005 and % HT > 80% at Φ(I) = 0.04. HTA appears to be a better antioxidant than HT, as shown by an accelerated oxidative test (Schaal oven method). A correlation between their distribution in the emulsion and their efficiency was established.
我们采用动力学方法来确定抗氧化剂羟基酪醇（HT）和羟基酪醇乙酸酯（HTA）在由脱臭橄榄油、酸性水和吐温 80 与司盘 80[亲水-亲脂平衡（HLB）=8.05]的混合物组成的模型食品乳液的油相、水相和界面区之间的分布。HT 不溶于油，但 HTA 既溶于油又溶于水（分配常数 P（O）（W）=0.61）。结果表明，在给定的乳化剂体积分数 Φ（I）下，HTA 在界面区的分数高于 HT。两种抗氧化剂的百分比均随 Φ（I）的增加而增加，因此在 Φ（I）=0.005 时 %HT>40%，在 Φ（I）=0.04 时 %HT>80%。加速氧化试验（沙尔烘箱法）表明，HTA 比 HT 具有更好的抗氧化性能。建立了它们在乳液中的分布与其效率之间的相关性。
