López-Varela S, Sánchez-Muniz F J, Garrido-Polonio C, Arroyo R, Cuesta C
Department de Nutrición y Bromatologia I. (Nutrición), Facultad de Farmacia Universidad Complutense, Madrid, Spain.
Z Ernahrungswiss. 1995 Dec;34(4):308-13. doi: 10.1007/BF01625343.
Standard chemical and physical indexes, such as color index, acid value, and K270 were compared with the polar content and the specific thermoxidative and hydrolytic compounds originated during 75 potato fryings with sunflower oil. The color index, acid value, K270 and total polar content showed a significant increase (p < 0.05) after the first 30 fryings, followed by a tendency of the last three indexes to reach a near-steady state. Triglyceride polymers and triglyceride dimers showed a significant increase (p < 0.05) after 30 fryings, while the oxidized triglycerides were not increased significantly after 30 fryings. The amount of diglycerides and free fatty acids related to hydrolytic alteration did not change significantly throughout the frying operations. The significant correlations between acid value and total polar content, triglyceride dimers, triglycerides polymers and oxidized triglycerides, or between color index and polar content and triglyceride polymers or between K270 and triglyceride polymers indicate that these simple and standard methods can be applied and they are as useful as more specific methods of evaluation in the monitoring of frying operations, provided that initial values of all of these indexes are available.
将标准化学和物理指标，如颜色指数、酸值和K270，与75次用葵花籽油炸薯条过程中产生的极性成分以及特定的热氧化和水解化合物进行了比较。在前30次油炸后，颜色指数、酸值、K270和总极性含量显著增加（p < 0.05），随后后三项指标有达到接近稳定状态的趋势。甘油三酯聚合物和甘油三酯二聚体在油炸30次后显著增加（p < 0.05），而氧化甘油三酯在油炸30次后没有显著增加。与水解变化相关的甘油二酯和游离脂肪酸的量在整个油炸过程中没有显著变化。酸值与总极性含量、甘油三酯二聚体、甘油三酯聚合物和氧化甘油三酯之间，或颜色指数与极性含量和甘油三酯聚合物之间，或K270与甘油三酯聚合物之间的显著相关性表明，这些简单的标准方法可以应用，并且在油炸操作监测中它们与更具体的评估方法一样有用，前提是所有这些指标的初始值是已知的。
