Instituto de la Grasa, Consejo Superior de Investigaciones Cientificas (CSIC), Padre Garcia Tejero 4, E-41012 Sevilla, Spain.
J Agric Food Chem. 2009 Nov 25;57(22):10505-11. doi: 10.1021/jf902009b.
The evolution of the fluorescent compounds during the thermal deterioration of virgin olive oil is not yet well-known. Samples of heated virgin olive oils collected from a fryer every 2 h up to 94 h were analyzed to study their fluorescence spectra as well as the evolution of the concentrations of alpha-tocopherol and individual phenols by high-performance liquid chromatography (HPLC). The regions of the fluorescence spectra of the heated oils, diluted in hexane at 1%, were explained by the content of these compounds with regression coefficients higher than 0.90 (R2 adjusted). The fluorescence intensity recorded at 350 nm and the wavelength of the spectrum maximum in the range of 390-630 nm also allowed for the explanation of the increase of the percentage of polar compounds during the experiment. On the other hand, the spectra of the undiluted heated oils indicated that the maximum of the spectrum of any undiluted oil at 490 nm or beyond is related to a percentage of the polar compounds higher than 25%, which is the maximum percentage accepted for edible oils used in frying processes.
在特级初榨橄榄油热劣化过程中，荧光化合物的演变尚不清楚。每隔 2 小时从油炸锅中收集加热的特级初榨橄榄油样品，直至 94 小时，然后通过高效液相色谱（HPLC）分析其荧光光谱以及 α-生育酚和个别酚类化合物浓度的演变。用回归系数高于 0.90（调整后的 R2）解释了在 1%己烷中稀释的加热油的荧光光谱区域。在 350nm 处记录的荧光强度和 390-630nm 范围内光谱的最大波长也可以解释实验过程中极性化合物百分比的增加。另一方面，未稀释加热油的光谱表明，任何未稀释油在 490nm 或更高处的光谱最大值与高于 25%的极性化合物百分比有关，这是油炸过程中可接受的食用油的最大百分比。
