Research progress on classification, source, application of phytosterol esters, and their thermal oxidation stability

Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases. It was found that phytosterol esters exhibited better solubility and bioavailability than free phytosterols. In recent years, phytosterol esters have attracted increasing attention. However, during food processing, phytosterol esters are susceptible to degradation at high temperatures, resulting in certain losses and formation of potentially harmful substances for humans. This paper reviews the relevant literatures and updates on the thermal oxidation stability of phytosterol esters in recent years from the following aspects: (i) Sources, physiological activities, and applications of phytosterol esters; (ii) Oxidation mechanism of phytosterol esters; (iii) Effects of phytosterols species, the volume of addition, food matrix, heating temperature and time, and antioxidants on the thermal loss and oxidation stability of phytosterol esters. The research progress on the safety of phytosterol esters is also discussed in detail. Additionally, the prospects for future research are highlighted.