甘油二酯热氧化稳定性的初步研究

PRELIMINARY STUDY ON THERMAL OXIDATIVE STABILITY OF DIACYLGLYCEROL

目的研究甘油二酯(diacylglycerol,DG)的热氧化稳定性。方法检测DG和大豆油在中油温加热(110℃)、高油温煎炸(180℃)和恒温贮藏(40℃)过程中酸价、过氧化值、p-茴香胺值和全氧化值的变化,以及DG在110℃加热过程中酯类种类和含量的变化。结果在不同加热温度条件下,随着加热时间的延长,DG和大豆油的酸价、过氧化值、p-茴香胺值及全氧化值均增高,DG的酸价高于大豆油,过氧化值、p-茴香胺值、全氧化值低于大豆油(P<0.05)。在中油温110℃加热过程中,随加热时间的延长,十八烷酸单甘油酯及单硬脂酸甘油酯含量均增高。结论与大豆油相比,DG热氧化稳定性较高,且在保证品质的前提下,储藏时间更长。

Objective To study the thermal oxidative stability of diacylglycerol（DG）. Methods DG and soybean oil were heated at the temperature of 110℃ for 12 min, at the temperature of 180℃ for two days, or stored at 40℃ for 7 weeks respectively. Changes of acid value, peroxide value, p-anisidine value, and total oxidation value after the treatments were detected. Moreover, we analyzed the changes of the esters during the heating process at 110℃. Results Under different heating temperature conditions, the acid value, peroxide value, p-anisidine value, and total oxidation value of DG and soybean oil were increased with the prolongation of heating time. Compared with soybean oil, the acid value of DG was higher, while the peroxide value, p-anisidine value and total oxidation value of DG were lower（P〈0.05）. The contents of 2-monostearin and monostearin were increased during heating at the temperature of 110℃. Conclusion Compared with soybean oil, DG had higher thermal oxidative stability and longer storage time.