Volatile compounds formed during heating of asymmetric distigmasterol-modified acylglycerols as indicators of thermo-oxidative degradation.

Phytosterols play a significant role for organisms. They are a component of cell membranes and also have transport functions. They are also important for lower human blood cholesterol levels. The asymmetric distigmasterol-modified acylglycerols (DStA) with oleic and palmitic acid were synthesized as new, more stable derivatives than free phytosterols. The new structure can improve phytosterols solubility in oil. The identification of more stable forms of phytosterols will allow their greater use as a food additive. Assessment of the volatile compounds formed during thermo-oxidative degradation of phytosterols (60 °C and 180 °C), which may affect the flavor of food products, is a rapid and sensitive method for evaluating phytosterol degradation. The GC/MS technique was used for the determination of volatile compounds. The aim of this work was to determine the volatiles formed during storage and thermal degradation of DStA in order to develop a rapid and sensitive system of measuring their degradation. The same compounds were identified for free stigmasterol, its esters with fatty acids, and new DStAs. Eight volatile compounds can act as indicators of sterol degradation during storage and heating. The synthesized 2,3-distigmasterylsuccinoyl-1-oleoyl-sn-glycerol (DStS-O) offered the highest thermo-oxidative stability during storage and thermal processing of all the examined acylglycerols.